bluuebunny/crossref_metadata_2025 huggingface dataset:
Age Changes of Bone Size and Mass in Two Strains of Senescent Rats
Authors: Riesenfeld Alphonse
Published: July 2008

6-month-old Buffalo and Fisher inbred rats were compared with their respective senescent counterparts. It appeared that length as well as weight of the various sections of the skeleton increased into old age. However, in some skeletal parts, length increase was greater than weight increase, so that relative robusticity of those parts, relating weight to lenght, dropped. The two different strains of rats showed differences in age-related bone reactions. Thus, while in humans, age-related bone loss is absolute, in rodents it is relative in certain sections of the body, or does not occur at allbut strain-dependent differences in rats have some parallels in human breeding populations.
Tissue Culture and Scanning Electron Microscopy of Breast Carcinoma ‘Cell Line MCF-7’ from Pleural Effusion
Authors: Rizk Nabil N. , El-Rakhawy M.T.
Published: July 2008

The surface ultrastructure of tissue-cultured cells derived from the pleural effusion of metastatic scirrhous breast carcinoma in the human MDF-7 cell line was studied by scanning electron microscopy. It was found to form monolayers of various colonies or collections of cells which were either separate or intimately adherent. The surface ultra-structure of the cells was found to be exclusively formed of microvilli. Data suggesting a diagnostic significance of microvilli in cancer cells were discussed. Observations were made which point to the existence of a compensatory absorptive functional activity exerted by the microvilli.
Histologische und proliferationskinetische Untersuchungen zum Wachstum der Rattenprostata in verschiedenen Lebensaltern
Authors: Stiens R. , Helpap B.
Published: July 2008

Histologic and cell-kinetic investigations were performed on the developing prostate of growing rats. The ages ranged from 1 day to 15 months. The most intensive cell proliferation is observed within the first 2 weeks after birth. Thereafter, the cell proliferation decreases continually as the cellular differentiation of the prostatic glandular epithelium increases to form well-differentiated secretory cells. The second peak of cell proliferation occurs with the beginning of sexual maturation and an elevated testosterone production. But the rapid increase of prostatic weight at that time is mainly caused by an increased formation of secretory and interstitial tissue fluids. The different lobes of the adult prostate all exhibit the same cellular proliferation pattern. The prostate belongs to the organs with stable growth pattern and an only small cellular turnover. Mitotic figures are extremely rare under normal conditions. But this low cellular proliferative activity may be easily changed, in contrast to other organs with stable tissue and steady-state growth, i.e., liver and kindney, in dependence of hormone levels.
Développement du fémur pendant la période de lactation, chez des rats dont les mères ont subi, au 10e jour de gestation, un traitement en vitamine A
Authors: Abreu Rays M. , Iucif S. , Lopes R.A. , Da Costa J.R.V.
Published: July 2008

Administration of a single dose of vitamin A (0.20 ml of Arovit, Roche, containing 30,000 IU of vitamin A palmitate), injected intraperitoneally in rats on the 10th day of gestation had the following effects on the femur of the newborn rats during lactation: longer femurs; earlier appearence of the epiphysial centers; a lower number of cells, increased matrix and consequent earlier maturation process for the zone of hypertrophic cartilage, and thicker and more numerous bone trabeculae. These data were confirmed by morphometric techniques.
Histological Changes in the Thyroid Gland Induced by Monosodium Glutamate in Mice
Authors: Dhindsa Kuldip S. , Omran Reff G. , Bhup Rohan
Published: July 2008

The effect of monosodium glutamate (MSG) on the thyroid gland of mice is studied. MSG induces marked histological changes in the thyroid tissue, indicative of hypothyroidism. The follicular epithelium, is greatly compressed and the follicles have enlarged due to distension with the accumulation of colloid. The histological picture of the thyroid gland remains unchanged for the animals sacrificed after short-term (13 weeks) and long-term (52 weeks) treatment. MSG, therefore, has a cumulative effect. The hypothyroidism is attributed to the influence of the drug on hypothalamus-pituitary function and the secretion of hormones responsible for the thyroid metabolism.
Occurrence of a Contractile Tissue in the Theca externa of Atretic Follicles in the Mouse Ovary
Authors: Motta Pietro M. , Familiari Giuseppe
Published: July 2008

In mature mouse ovaries, smooth muscle cells (SMC) are as a rule concentrated in the perifollicular stroma of developing follicles but are also present in different ovarian regions. In growing antral follicles SMC form a conspicuous investment (‘capsule’) of concentric layers of stretched and elongated elements located in the zones of the theca externa. On the contrary, in antral follicles reaching approximately the same growth phase but with clear signs of atresia, the contractile capsule of the follicles has an irregular outline due to an apparent dislocation and shortening of SMC. The ultrastructural findings show that in atretic follicles the majority of the cells forming this capsule possess the cytological characteristics of SMC fixed in contraction. The occurrence of compressed SMC in the wall of atretic follicles suggests that some relationship exists between follicle contraction and the atretic process. In the case of the follicle at ovulation, it may be suggested that the activation of such perifollicular contractile tissue, even if incapable of producing alone the dehiscence of the follicle, may nevertheless be capable of squeezing the follicular wall. Then, if other factors do not simultaneously occur to cause a normal ovulatory processs, the contraction of this tissue, instead of assisting in the rupture of the follicle, may favor its collapse and subsequent involution during atresia.
Scanning-Electron Microscopy Studies of ‘Ground Substance’ in the Cement Lines, Resting Lines, Hypercalcified Rings and Reversal Lines of Human Cortical Bone
Authors: Frasca Peter
Published: July 2008

Adult human cortical bone was decalcified and stained with Harris’s hematoxylin, which has a strong affinity for cement lines, resting lines, hypercalcified rings and reversal lines. Small pieces of bone tissue containing these morphological entities were then dissected and manipulated mechanically so as to disrupt them partially. Scanning electron microscopy of these regions of interest revealed the presence of relatively large concentrations of amorphous ‘ground substance’ which was morphologically distinguishable from the fibrous collagen fiber bundles located in the adjoining collagen-rich lamellae. The methodology used in this study confirms the existence of the above-mentioned regions as true morphological entities and also makes possible enzymatic studies designed to identify the major biochemical components constituting the observed ‘ground substance’.
Morphology of the Veins Draining the Coronary Sinus of the Dog
Authors: Esperança Pina J.A. , Correia M. , O’Neill Goyri , Rendas Bensabat
Published: July 2008

The morphology of the superficial cardiac veins draining the coronary sinus was investigated in 47 normal adult dogs, using the injection-corrosion-fluorescence technique. The veins pertaining to the left coronary territory all drain directly to the coronary sinus and include the following vessels: the great coronary vein and its tributaries, the left posterior atrial and ventricular veins. The veins pertaining to the right coronary territory include the posterior interventricular vein and the small cardiac vein. A comparison with the human pattern was made, particularly regarding the number of interventricular septal branches and it was suggested that such a reduction in number in the dog could be due to a take-over from the Thebesian veins in the venous drainage of the interventricular septum.
Studies on Orthocephalization
Authors: Vilmann Henning , Moss Melvin L.
Published: July 2008

The positional stability of the zygomatic arch of the rat skull in relation to the parietal bone, the basisphenoid bone and the length axis of the skull, as previously demonstrated in rats older than 14 days, does not exist to the same degree in younger rats. These conclusions have been drawn from a study of a sample of rats, aged 0, 4, 7 and 14 days. These 4 groups of rats have been x-rayed after sacrifice, and from the x-ray photographs, quantitative expressions of angular values between the mentioned structures have been obtained. The most important result is, however, considered to be, that a full description of the behavior of the external cranial frame of the rat skull is now available for further studies on the process of orthocephalization. res during orthocephalization of the rat skull.
Alteration of Scapular Morphology through Experimental Behavioral Modification in the Laboratory Mouse (Mus musculus)
Authors: Kimes K.R. , Siegel M.I. , Sadler D.L.
Published: July 2008

It is demonstrated that the behavior/morphology interface can be studied in controlled experiments. The normal locomotor behavior of the laboratory mouse (Mus musculus) was modified so that animals were restricted to either a plantigrade, ‘non-climbing’, control environment or an experimental, suspensory, ‘climbing’ environment. Distinct scapular correlates of the modified behavior were observed. Climbing experimental animals exhibited narrower scapulae with angular measurements consistent with reduced scapular breadth. Plantigrade control animals exhibited broader more squared scapulae. It is suggested that the methodology used here can be extended to natural populations with analagous locomotor behaviors.
Volumetric Comparison of the Accessory Olfactory Bulb in Bats
Authors: Frahm Heiko D.
Published: July 2008

Accessory olfactory bulb (AOB) volumes were calculated in 26 chiropteran species. The percentage of the AOB in relation to the olfactory bulb complex ranges between 0.18 and 2.70%. The allometric comparison reveals the high development of this structure in the phyllostomatid subfamily of Glossophaginae. Carolliinae and Sturnirinae are near the chiropteran average. Smaller AOBs can be observed in Sphaeronycteris, Diphylla, Pteronotus parnellii and Miniopterus schreibersi. Comparison of the right/left AOB size in 56 specimens showed a slight predominance of the latter (average 50.6% of total volume). Intraspecific variability of this structure is pronounced, reaching a maximum SEM of 23.2% in Artibeus lituratus. Other species with well-developed AOBs tend to show high intraspecific variability. The role of the accessory olfactory system is seen by recent investigators mainly in its participation in sexual behavior and in close connection with the ‘Flehmen’ gesture, which is predominantly shown by male individuals. When comparing the size of the AOB in 18 bat species where both sexes were represented, only half of them showed smaller AOBs in females. This demonstrates that there is no tendency towards reduction of this structure in females.
Effects of Isoprenaline Treatment on the Rat Liver Parenchyma
Authors: Barni S. , Speziali M. , Polver De Piceis , Fenoglio C.
Published: July 2008

Ultrastructural modifications of liver cells were studied in adult rats treated with high doses of isoprenaline for 8 days and subsequently sacrificed at various times up to 25 days from the beginning of treatment., The most evident changes were observed at the earliest times after the end of treatment. They involved both the nucleus (changes in shape and chromatin organization) and cytoplasmic organelles such as the rough endoplasmic reticulum and the smooth endoplasmic reticulum, the latter exhibiting marked dilation and increase, while glycogen generally appeared to be decreased. At later times after the end of treatment, these changes tended to disappear, while there was an increase of peroxisomes and particularly of lysosomes, which exhibited a clearly polymorphic pattern.
Fine Structure and Myelination of the Developing Human Vagus Nerve
Authors: Woźniak Witold , O'Rahilly Ronan
Published: July 2008

The development of the cervical part of the vagus nerve was studied by electron microscopy in 17 human embryos and fetuses from 18 to 220 mm crown-rump (CR) length, approximately 7–23 postovulatory weeks old. By the end of the embryonic period proper, processes of neurolemmocytes are beginning to invade the nerve bundles of the vagus. Early in the fetal period, the nerve fibres become more regularly arranged, the lemmocyte/axon ratio is diminishing, the neurolemmocytes are dividing, and the connective tissue elements are becoming differentiated. By 14 postovulatory weeks (120 mm CR), examples of a 1:1 lemmocyte/axon ratio are observed, and the spiral development characteristic of myelination is beginning. By 17 weeks, myelinated fibres at varying phases of myelinogenesis are apparent, and desmosome-like junctions in the opposed plasma membranes are seen where lemmocyte processes form a mesaxon. By 23 postovulatory weeks, the diameter of the axons varies from 0.2 to 3.5 µm, and the vagus shows its mature structure, although nerve fibres at the beginning of myelin formation are still visible.
The Fine Structure of Snake Myocardium
Authors: Leeson Thomas S.
Published: July 2008

Snake myocardium has been studied using standard methods and tannic-acid mordanting. In both atria and ventricle, cells were arranged in fascicles with little connective tissue, up to 20 cells per fascicle, and few differences between cells of atria and ventricle. Cell (fiber) size varied from 8 to 12 µm in the nuclear area with a few cells up to 14 µm in ventricle, and cells generally were spindle-shaped, tapering toward the extremities where relatively simple intercalated discs were seen. Few myofibrils per cell were present and poorly delineated. Transverse tubules were absent and sarcoplasmic reticulum was poorly developed and, apparently, even absent from some cells. All cells contained micropinocytotic vesicles associated with the surface plasmalemma and subsarcolemmal caveolae. In addition to intercalated discs, intercellular junctions showed spot desmosomes, small and sparse gap junctions and fasciae adherentes of two types, one associated with Z-bands, one independent of Z-bands. Nerve fibers and nerve endings were numerous, particularly in atrium. These findings are discussed in relation to the structure of mammalian myocardium.
Effects of Isoproterenol on the Ultrastructure of Pig Parotid Gland
Authors: Boshell Jerry L.
Published: July 2008

Following chronic administration of isoproterenol, the parotid glands of the domestic pig were removed and studied with transmission electron microscopy. Acinar cells were markedly altered, whereas ductal elements were apparently unchanged. A notable hypertrophy of Golgi membranes was observed. In addition, electron-dense bodies located near the Golgi membranes were more numerous after isoproterenol administration.
Dense Bodies in Bronchiolar Ciliated Cells of Rats
Authors: Baert Johan H. , Vandenberghe Marie-Paule
Published: July 2008

The bronchiolar ciliated cells of rats usually contain two large electron-dense bodies which are individually surrounded by a unit membrane. They lie in a well-defined supranuclear position and may indent the nucleus. The dense material is digested by pepsin, suggesting it is composed of protein. The origin and function of these bodies are still unknown.
Some Histological and Histochemical Studies of the Pancreas of the Brasilian Sloth, Bradypus tridactylus
Authors: Pinheiro P.B.N. , Coutinho H.B. , Aguiar F.J.C. , Pessoa R.G. , Abrahamsohn P.A. , Pallot D.J. , Coutinho V.B.
Published: July 2008

The histological and histochemical study of the pancreas of the three-toed sloth, Bradypus tridactylus, demonstrated that with the methods employed the pancreatic islets are apparently formed by A cells exclusively. Two different types of argyrophilic cells were noticed in the exocrine secretory units when Grimelius’ method was used. The methods for the demonstration of D cells showed negative results. Aldehyde fuchsin-positive granules were only noticed at the apex of the exocrine pancreatic cells. These results are discussed in relation to current hypotheses concerning the evolution of insulin secretion mechanisms.
Evidence for Increased Protein Synthesis in Myocardial Microvessels after Chronic Sympathectomy in the Dog
Authors: Jones Carl E. , Cannon Samuel
Published: July 2008

Using histochemical methods, evidence of increased protein synthesis was observed in microvessels (diameter < 100 µm) from dog hearts which had been sympathectomized 2 weeks earlier when compared to controls. Such evidence consisted of increased staining intensity for the enzyme glucose-6-phosphate dehydrogenase and for the nucleic acids RNA and DNA. Increases in reaction intensities were noted in approximately 30% of the microvessels examined from the sympathectomized hearts, and may imply a vascular proliferation in these hearts. However, since no increase in capillary density was observed in sympathectomized hearts, a vascular proliferation, if it occurred, may have been involved in development of the coronary collateral circulation. These data support previous results indicating that collateral resistances are reduced following chronic cardiac sympathectomy while resistance of the coronary vascular bed itself is not altered.
Swelling of Mitochondria in Immersion-Fixed Liver Tissue
Authors: Rømert P. , Matthiessen M.E.
Published: July 2008

In order to study the occurence of swollen and disrupted mitochondria in tissue preserved for electron microscopy by ordinary fixation methods, liver tissue from miniature pig fetuses was immersion-fixed in fixatives with various types and concentrations of fixing agents and vehicles. Also commercial and purified products have been tested, different fixation times and temperatures as well as the consequences of a short rinsing in buffer solutions prior to fixation. Furthermore, the significance of delayed fixation (autolysis) was studied. It was found that swollen and disrupted mitochondria occur predominantly in liver cells exposed to low concentrations of glutaraldehyde. It is shown that this phenomenon is a result of a specific effect of glutaraldehyde on the mitochondrial membranes. It is not accompanied by parallel changes of other organelles or nuclei, and it is not provoked by other fixing agents, vehicles or by delayed fixation (autolysis).
Quantitative Ultrastructural Study of Prolactin Cells from Lactating Mice during a 24-Hour Period
Authors: Souto Marta , Gómez Dumm César Leandro Alberto
Published: July 2008

A quantitative ultrastructural morphometric study was performed on the prolactin (PRL) cells of lactating mice, at different times in a circadian period. The results showed significant time fluctuations in the percentages of cytoplasmic volume occupied by several organelles. The endoplasmic reticulum appeared more developed during the dark period, indicating a higher synthesis of secretory material in this phase. The Golgi complex, including an increased number of immature granules, was found remarkably enlarged during the light period. Moreover, the release of PRL would be increased during the dark phase, as judged by the diminution of the secretory granules and the higher degree of emiocytotic activity. The present morphometric approach in the detection of circadian variations of PRL secretion in lactating mice is emphasized.
Etude histologique de l’action du Propranolol sur l’appareil génital du rat mâle
Authors: Martinez D. , Barthe D.
Published: July 2008

Increasing doses of propranolol were injected intraperitoneally to four series of adult male rats in order to study the effect of this β-blocking agent on various organs (testis, epididymis, prostate and seminal vesicle) and endocrine glands (adrenals, pancreas, thyroid, pituitary). Histological damage was observed only in testes: i.e., necrosis and desquamation of germinal cells in the seminiferous tubules associated with light arterial vasoconstriction. Pelviperitoneal fibrosis was observed as well. These lesions seem to be of pharmacological vascular origin and appear to occur in combination with an elective toxic effect of propranolol on the germinal cells.
Effect of Alizarin Red S on Rat Blood and Its Calcium Content
Authors: Isotupa Kauko , Virtanen Pauli
Published: July 2008

The vital staining mechanism of alizarin red S (ARS) was investigated. The total calcium content of rat blood was determined after intraperitoneal and intracardial administration of acidic, neutralized and calcium-supplemented ARS. The administration of ARS causes, irrespective of chemical state, a remarkable decrease in blood volume and a significant decrease in the serum/blood ratio. The total calcium content of rat serum was noticeably increased, more in the case of intracardial than in the case of intraperitoneal administration. The calcium values determined in this work were the sums of free and bound calcium. The increase in calcium content even in those cases where ARS was administered without calcium indicates a physiological ability to keep the concentration of free calcium constant in the blood. The highest calcium values were found when calcium-supplemented ARS was administrated. The physiological activity, however, seems to be higher with acidic ARS, which also contributed to the vital staining effect on rat skull. The best staining with least inconvenience was achieved using neutralized ARS for in vivo staining.
Ultrastructural Relationships between the Receptor Nerve Fiber and Surrounding Lamellae in Krause End-Bulbs
Authors: Spassova Irina
Published: July 2008

The ultrastructural relationship between the receptor nerve fiber and the surrounding lamellae in Krause end-bulbs was discussed. Many sites of specialized junctions of symmetrical or asymmetrical type along the receptor nerve fiber and the surrounding lamellae were found. In addition, in close vicinity to them, spine-like digitations of the receptor nerve fiber, filled mainly with small clear vesicles, were observed. Mitochondrion-like cholinesterase-positive structures bulging in some cytoplasmic lamellae were also found. It is suggested that a functional link might exist between the specialized junctions, digitations and mitochondrion-like structures in the transformation of external mechanical stimuli into nerve impulses.
Adaptation of Arterioles to Moving Capillaries
Authors: Moe Harold
Published: July 2008

The capillary network of the enamel organ of the continuously growing mandibular incisor of the rat is supplied by a series of arteries which, after penetrating the bone, are disposed in a row in the periodontium along the tooth and linked together by anastomoses. The branches from these arteries are subjected to adaptive changes consistent with a forward movement of the capillaries in relation to the arteries. The mechanism which renders this movement possible appears to be the following: Each artery in the row supplies a section of the passing plexus by coupling and uncoupling short-lived arterioles, which go through a cycle of proliferation, elongation and degeneration. Proliferation takes place at the posterior end of the section, where new arterioles replace discarded arterioles from the preceding artery. By growing in length, the arterioles keep pace with the migrating capillary network. When the capillaries are within reach of the next artery, the arterioles disconnect. Thereafter they become obliterated and die in the intermediate zone of the periodontium, to which they have been gradually displaced by proliferation of the inner-tooth-related layer of the periodontal connective tissue.
Evidence for Penetration of Intraperitoneal Horseradish Peroxidase into Vagal Preganglionic Neural Elements
Authors: Shoumura Shizuko , Shoumura Kazuhiko , Isono Hideo
Published: July 2008

Intraperitoneal horseradish peroxidase was found to penetrate directly into the vagal preganglionic neural elements. After intraperitoneal administration of horseradish peroxidase, the bilateral dorsal nucleus of vagus nerve was labelled retrogradely with the enzyme. Other regions of medulla oblongata and sacral spinal cord were free from labelling. The significance of these findings was considered in relation to studies of autonomic nerve supply of abdominal viscera using retrograde transport of horseradish peroxidase.
Die Kiemenbogenentwicklung bei Ratte und Maus
Authors: Kaufmann P. , Leisten H. , Mangold U.
Published: July 2008

The development of the branchial arch region was studied in mouse embryos at the age of 10–13 days after conception [end of embryonal day (ED) 10 to end of ED 13] and in rat embryos at the age of 11–14 days after conception (end of ED 11 to end of ED 14) using SEM and serial semithin sections. Special attention was paid to the development of the cervical sinus and the branchial operculum. In both rodents, a typical operculum was not found. Instead, the caudal branchial arch region was remodeled by a rapid growth of the second branchial arch, the retrobranchial ridge and the epipericardial ridge, thus forming a progressively deeper groove in this region, the sinus cervicalis. The epithelium of the fourth and sixth branchial archs participated in the formation of the vagus placode, which in later stages was depressed into a groove dorsally and lost its connection with the surface. Finally, the second branchial arch and the cardiac bulge fused compressing the third branchial arch, the second and third branchial grooves and the aperture of the vagus placode. A typical vesicula cervicalis, lined by ectodermal epithelium and collecting the second, third and fourth branchial grooves and the glossopharyngeal and vagus placodes, was not found. However, single or multiple slit-like lumina may persist within the epithelial remnants of the second and third branchial grooves and the vagus placode.
Die Kiemenbogenentwicklung bei Ratte und Maus
Authors: Mangold U. , Dörr A. , Kaufmann P.
Published: July 2008

The development of the branchial arch region was examined at 6- to 12-hour intervals in mice embryos at the age of 9.5–11.5 days after conception [middle of embryonal day (ED) 10 to middle of ED 12] and in rat embryos at the age of 10.5–12.5 days after conception (middle of ED 11 to middle of ED 13) using SEM, serial semithin sections and wax plate reconstructions. The 4th branchial groove is always separated from the corresponding pharyngeal pouch by a broad layer of mesenchyme. At no time did we find a membrana obturans in this region. However, during development the mesenchyme disappears between the branchial grooves and pharyngeal pouches of the first four arches, allowing external ectodermal epithelium to come into contact with the internal endodermal epithelium to form a membrana obturans. In its dorsal parts this membrane is formed by two layers of epithelium, in the ventral portion frequently it consists of only one layer of epithelium. It was not possible to determine whether the latter was derived from ectoderm or endoderm. Degeneration of cells in this ventral part of the membrane leads to openings which we consider to correspond to branchial clefts. The possibility of an artefactual genesis of these membrane ruptures is discussed. The ‘1st branchial cleft’ appears in mice embryos at the age of 9.75 days (second half of ED 10), the ‘2nd branchial cleft’ appears first at the age of 10.5 days (middle of ED 11), and the ‘3rd branchial cleft’ appears at the age of 11 days (end of ED 11). In the rat, the corresponding developmental stages are seen about 24 h later. Whereas the ‘1st and 3rd branchial clefts’ are demonstrable during a period of maximally 12 h, the ‘2nd branchial cleft’ is present during a developmental period of about 24–36 h. This protracted existence of the ‘2nd branchial cleft’ is possibly related to the occurrence of lateral cervical fistulas and cysts in the region of the second branchial arch.
Oil Droplets in the Chameleon (ChamaIeo chamaleo) Retina
Authors: Armengol J.A. , Prada F. , Génis-Gálvez J.M.
Published: July 2008

The cones of the chameleon retina have, in the scleral portion of their inner segment, an oil drop whose morphology is similar in all the photoreceptors possessing this droplet. The irregularities in the membrane surrounding the lipid matrix show close relationships with the surrounding mitochondria.
Variations in the Axon Reaction in Animals of Different Ages
Authors: Søreide Arvid J.
Published: July 2008

The retrograde nerve cell reaction was studied after crush lesion of the facial nerve in rats of different ages. Neuronal survival increased from 10% in newborn rats to 100% in adults. In 8- or 10-day-old animals axotomy caused central chromatolysis, nuclear eccentricity, folding of the nuclear membrane, and development of nuclear caps. Similar lesions in adult rats caused only minimal changes. The findings differ from those previously reported in hamsters [La Velle and La Velle, 1958a, b, 1959], where chromatolysis was most severe in adult animals. However, the neuronal survival followed the same age-related pattern in rats and hamsters. Thus, there are marked species differences in the chromatolytic response after axotomy, but these differences do not affect neuronal survival. It is concluded that chromatolysis is not a decisive factor for neuronal recovery after axon injury in young animals.
Structures of the Bovine Vomeronasal Complex and Its Relationships to the Palate: Tongue Manipulation
Authors: Jacobs V.L. , Sis R.F. , Chenoweth P.J. , Klemm W.R. , Sherry C.J.
Published: July 2008

The rostral part of the bovine vomeronasal complex was examined to determine its relationships to structures of the palate which are compressed by the tongue during investigative sexual behavior. The rostral vomeronasal cartilage (VNC) is C-shaped and contains the incisive duct (ID). The hilus of the cartilage is directed medially, approximately 0.5 cm dorsal to the palate. Just caudal to the origin of the vomeronasal duct, the VCN lies approximately 1 cm above the palate with a ventrally oriented hilus containing the ID. Further caudally, the hilus is directed laterally, toward the nasal cavity. Palatal mucosa occupies the intervomeronasal, cartilaginous area below the nasal septum and caudal to the incisive papilla. This mucosa and the ID appear to be compressed by the bull’s everted tongue, forcing fluid samples into the vomeronasal system.
Etude ultrastructurale des neurones ganglionnaires spinaux au cours du vieillissement chez le rat
Authors: Van den Bosch de Aguilar P. , Vanneste J.
Published: July 2008

The chronology of the alterations impairing the cytology of the spinal ganglion neurons was analysed in 3- to 32-month-old male rats. A type neurons are impaired earlier and more severely than B neurons. Ageing alterations occur during two successive periods. During the first period, beginning at about 3 months, lipofuscin pigments gradually accumulate in the neurons. During the second period, beginning at about 24 months, various kinds of inclusions appear (granulofilamentous bodies, nematosomes,...); some of which could be originating from altered microtubules and/or filaments. At the same time, lipofuscin pigments are more heterogeneous. This period might be the onset of real senescence and of the gradual deterioration of the neuronal function.
The Motor and Proprioceptive Innervation of the Retractor Bulbi Muscle of the Lamb
Authors: Palmieri Giovanni , Panu Rino , Asole Anna
Published: July 2008

The motor and proprioceptive innervation of the retractor bulbi muscle of the lamb has been studied. The motor innervation of this muscle is supplied only by the abducens nerve. The proprioceptive nervous fibers coming from the muscle spindles of this extraocular muscle enter the brain stem through the ophthalmic branch of the trigeminal nerve and have their perikarya in the semilunar ganglion.
Innervation of the Rat Preputial Gland
Authors: Ambadkar P.M. , Vyas D.M.
Published: July 2008

Acetylcholinesterase, butyrylcholinesterase and monoamine oxidase activities were observed in the neuronal and non-neuronal components of the preputial gland. Histological, histochemical and experimental studies clearly indicate that the preputial gland of the rat is innervated by cholinergic as well as adrenergic nerves.
Enhanced Responsiveness of Lactotrophs in Ectopic Pituitaries to Bromocryptine and Estrone Acetate
Authors: McComb Donna J. , Horvath Eva , Kovacs Kalman , Ryan Nancy , Domokos Istvan , Laszlo Ferenc A.
Published: July 2008

Intrasellar and transplanted pituitaries removed from the same rats were studied using light microscopy, immunocytology, electron microscopy and ultrastructural morphometry following treatment with bromocryptine and/or estrone acetate. Ectopic lactotrophs of rats treated with bromocryptine showed an increase in storage granule size and number, which was not observed in the lactotrophs of corresponding intrasellar pituitaries. In lactotrophs of intrasellar and ectopic pituitaries, treatment with estrone acetate caused a decrease of storage granule size, while rough endoplasmic reticulum (RER) and Golgi region volume density increased. When rats were treated with a combination of bromocryptine and estrone acetate, intrasellar lactotrophs exhibited increased volume density and diameter size in forming granules as well as increased RER volume density. In ectopic lactotrophs, combined treatment led to a decrease in RER, volume densities of Golgi region and forming granules, as well as increased storage granule size. It can be concluded that ectopic lactotrophs were more sensitive to the inhibiting effects of bromocryptine treatment than intrasellar lactotrophs. Intrasellar lactotrophs were more susceptible to estrone acetate than bromocryptine treatment. As a result, the increased responsiveness of ectopic lactotrophs to estrone acetate was less conspicuous.
Cell Production of Different Growth Plates in the Rabbit
Authors: Thorngren K.-G. , Hansson L.I.
Published: July 2008

In different growth regions of the long bones of normal rabbits the cell production in the growth plates were calculated from values of longitudinal bone growth determined with oxytetracycline and values of the degenerative cell size. The cell production was found to decrease similarly with increasing age for all growth regions. The rate of cell production for the various growth plates differed. There was little influence by age or localization on the size of the degenerative cells in the growth plate. Compared to other species such as rat and man the cell size in the rabbit is almost the same, whereas the difference in growth rate depends mainly on the cell production – mitotic activity – in the growth plate.
An Orthograde Labelling Study of Axons of the Dorsal Motor Nucleus of the Vagus to Rat Cardiac Ganglia as Demonstrated by Autoradiography
Authors: Sullivan James M. , Connors Natalie A.
Published: July 2008

Central organization of the cardiac vagus has not been clarified. Retrograde changes produced in medulla oblongata neurons after section of vagal branches has favored the dorsal motor nucleus of the vagus (DMNX). Current information concerning the origin, course, and termination of vagal preganglionic fibers within cardiac ganglia is conflicting. The explicit purpose of this study was to determine if vagal fibers originated specifically within the DMNX proper. Fibers within the cardiac ganglia were labelled with 3 H-leucine following injection into the DMNX. 12 adult albino rats were studied. DMNX were injected with 25 µCi 3H-leucine reconstituted to 5 µl. Animals were sacrificed by transcardial perfusion following a 4-day survival period. Serial cross-sections of the caudal pons, medulla oblongata, and thoracic viscera were processed for autoradiography. DMNX possessed a heavy incorporation of the radiochemical. Label was observed within the axons of the vagi. Cardiac ganglia contained labelled vagal fibers in close proximity to the postganglionic somata. Cardiac ganglia containing labelled preganglionic vagal axons were located in the cardiac plexuses and in the epicardium. Results show a labelled vagal preganglionic input to cardiac ganglia from the DMNX.
Effect of Age, Sex and Nutrition on Discontinuous Traits of Rat Skull
Authors: Dahinten Silvia L. , Pucciarelli Héctor M.
Published: July 2008

The effect of biological (age and sex) and environmental factors (proteincalorie malnutrition and protein deficit) on 24 discontinuous cranial traits was investigated in Holtzman rats. The traits affected were (a) the interfrontal fusion, by age and nutrition; (b) the double posterior palatine foramen, by sex and nutrition, and (c) the double maxillary foramen, by nutrition. It is concluded that most of the traits studied were fairly stable. Nevertheless, it must be pointed out that taxonomic studies based on discontinuous cranial traits should be interpreted with care due to the influence of environmental and biological factors on the phenotypic expression of some of them.
In vitro Analysis of Ovarian Differentiation and the Initiation of Meiosis in the Rat
Authors: Stein Larry E. , Anderson Everett
Published: July 2008

Intact, cranial, and caudal portions of fetal rat gonads on days 13, 14, 15, 16 and 17 of gestation were cultured singly on Nucleopore filters in Eagle’s MEM and McCoy’s 5A media (both supplemented with fetal calf serum and glutamine) to evaluate the role of the mesonephros in mammalian gonadogenesis. After 2–7 days in culture, in vitro and in vivo control tissues were examined by light and electron microscopy to determine the extent of morphological differentiation and gonium maturation. The onset of morphological differentiation and meiotic activity, as determined by synaptonemal complex formation, was found to be independent of the mesonephric epithelium. Ovaries and testes were also cultured as heterologous pairs on opposite sides of collagencoated Nucleopore filters for 4–6 days in McCoy’s 5 A media. In the absence of transfilter cellular migration and establishment of cell-to-cell contact, the in vivo pattern of sexual dimorphic onset of meiosis was observed. This finding lends support to the concept that local somatic-germ cell associations as opposed to extragonadal factors, are capable of providing the necessary environment for regulation of meiosis in the fetal rat.
Vascular Feature of the Hypophysis in Bubalus buffalus
Authors: Paino Giuseppe , Langella Michele , Caputo Giuseppe
Published: July 2008

The hypophysis of Bubalus buffalus was examined morphologically and compared to that of the bovine. The morphology and behavior of the vessels supplying the hypophysis and their contribution to the hypophyseal portal system were described. We found characteristic vascular arches between the pars tuberalis and the infundibulum from which the portal vessels originate. These vessels may be divided into long and short vessels, have different origins and extension, and branch in different regions of the anterior lobe.
Ultrastructural Changes in Tissue Columns of Fundus striati (Nucleus accumbens) Surgically Isolated from all Extrastriatal Connections
Authors: Ahn E.-T. , Hassler R. , Wagner A. , Christ J.F.
Published: July 2008

Following columnar isolation of fundus striati (nucleus accumbens) tissue from all afferent and efferent connections, the ‘aspiny’ giant cells of the striatum, which are electron microscopically characterized by many axosomatic synapses, undergo severe retrograde dark degeneration. In the same experiments, a less severe penumbral degeneration of large ‘aspiny’ neurons (large type I neurons of Mori) was observed. In contrast, the somata of 90–95% of the striatal cells that fall under the category of ‘spiny type I neurons’ show only minor changes in the form of cytoplasmic swelling or pale alteration. The same bland alteration is seen in the dwarf cells, which substantiates the general opinion that they are Golgi type II nerve cells. It is concluded that the efferent fibers of the giant and large types of neurons leave the striatum and project to the substantia nigra and the pallidum, respectively. This conclusion is based on the general pattern of retrograde degeneration due to axonal lesions. The severe dark degeneration of the large and giant ‘aspiny’ neurons indicates that a great length of the axon (with axon collaterals) has been separated from the trophic center. It is therefore suggested that these neurons project to the substantia nigra. The less severe penumbral degeneration of the large ‘aspiny’ neurons is probably the expression of a more distal interruption of their axons. It is, therefore, assumed that they conduct impulses to the adjacent pallidum. The pale alteration of the small ‘spiny’ neurons represents a mere ‘irritation’, without a direct mechanical injury to their axonal processes. Consequently, the vast majority of the ‘spiny’ neurons are regarded as intrinsic striatal interneurons which do not send efferent axons beyond the boundaries of the striatum. These results seem to support the classic view that the striatum is an integrating structure consisting of many small interneurons, a few dwarf cells and a relatively small number of giant and large projecting neurons.
Regional Distribution of Acetylcholinesterase Activity in the Brain and Hypophyses of Crossbred European Boars Reared in the Humid Tropics
Authors: Egbunike Gabriel N.
Published: July 2008

The distribution of acetylcholinesterase (AChE) activity in the brain and hypophyses of crossbred European boars that had been raised and maintained in the humid tropics was studied. AChE activity varied between brain and hypophyseal parts. Compared to results obtained from rats, the results of this study imply some evolutionary changes in the importance of the different brain parts with respect to the regulation of animal behaviour.
Scanning Electron Microscopy of Rat Neurointermediate Lobe Cells in Culture
Authors: Zimmerman A.E. , Milligan J.V. , Joneja M.G.
Published: July 2008

Enzymatically dispersed cells of the rat pars nervosa – pars intermedia (NI) were observed by scanning electron microscopy after 1, 2 and 4 days in culture. The cells attached to the plate slowly, requiring about 3–4 days for the majority to adhere. The epithelial cells became attached singly and in clumps and branched chains, often over a bed of fibroblast-like cells. After the first day in culture, few surface features were evident on the NI cells, but by day 2, the surfaces showed a small number of blebs. In 4-day cultures, the cells revealed extensive areas with blebs and microvilli, and a few structures resembling cilia were observed. The adrenocorticotrophic hormone content of the cells after 4 days in culture was similar to that found in fresh tissue.
Contribution à l’étude de la vascularisation du muscle tenseur du fascia lata
Authors: Mairesse J.L. , Mestdagh H. , Bailleul J.P. , Depreux R.
Published: July 2008

The tensor fascia lata is a short flat muscle arising from the anterior superior iliac spine and inserting into the fascia lata at mid thigh. It is supplied by three arterial pedicles of unequal importance, branching from the external iliac, gluteal and deep femoral arteries. The ‘dominant’ blood supply is carried by the lateral circumflex femoral artery which comes from the deep femoral and enters the muscle, approximately 8.8 cm beneath the anterior superior iliac spine. This vessel varies in size from 2 to 3.5 mm; it is 8 cm long but can be lengthened by ligating the branch for the vastus lateralis. On the deep sheath of the iliotibial tract it gives off three branches which supply each third of the fleshy body. The upper branch runs vertically to the iliac insertion of the muscle but not so far as the iliac crest and provides no cutaneous twig. On the contrary, the mid branch runs transversally through the muscle and sends perforating vessels to the skin overlying the fascia lata 6–7 cm below the anterior superior iliac spine. The descending branch runs parallel to the muscular fibers of the muscle and supplies the skin of the lateral lower thigh down to 8 cm above the knee. So the pedicle supports an area of skin which is double the length (22 cm) and triple the width (9.5 cm) of the fleshy body. The tensor fascia lata including the two layers of the iliotibial tract but excluding its upper insertion, together with the skin of the lateral aspect of the thigh can be safely used as a myocutaneous flap for covering defects of the trochanteric, ischial and sacral areas.
Ultrastructural Analysis of Skeletal Muscle Development in the Fetal Pig
Authors: Campion Dennis R. , Fowler Steven P. , Hausman Gary J. , Reagan James O.
Published: July 2008

Myogenesis was investigated at the ultrastructural level in the fetal pig at 35, 52, 65, 80, 95 and 110 days of gestation. At each stage of gestation, the predominately type II fiber type portion of the peroneus longus and sartorius muscles was examined. The sequence of events for normal myogenesis in the pig was generally similar to that reported for the skeletal muscle of other vertebrate species. In addition, the time interval for sequential development of myogenesis was similar between the two muscles. Centrioles were identified in primary fetal fibers and also in secondary fibers. No morphological evidence of mitotic activity was found in the myonuclei. The organization of myofibers into fasciculi was unrelated both temporally and spatially to capillary and neural development.
Origin of Renal Arteries from the Aorta
Authors: Keen Edwar Norman
Published: July 2008

The origin of single renal arteries from the sides of the aorta were examined in 52 dissecting room subjects. Although subject to variation, the right artery usually arose anterior (nearer the anterior midline) and superior (higher on the aorta) to the left renal artery. The left artery normally arises in front of the strict lateral (90°) position.
Satellite Cells in the Latissimus dorsi of the Rat
Authors: Allam Ali M.
Published: July 2008

This study was carried out with the aid of the electron microscope to determine the frequency of satellite cells in mammalian skeletal muscle fibre. 10 normal adult male albino rats were used and specimens from the latissimus dorsi muscle were removed, processed and prepared for electron microscope examination. Satellite cells were first identified by their location, shape and organelles. Counts were then carried out on 72 electron microscope fields at × 8,000 magnification from both longitudinal and transverse sections. The total number of nuclei was counted first, then the nuclei of satellite cells were identified and recorded. It has been found that satellite cell nuclei accounted for only 4.5 % of all the nuclei seen. The rest being myonuclei within the muscle fibre. This surprisingly small number of satellite cells leaves the question of their role in muscle regeneration and that of the origin of the large numbers of ‘myoblasts’ that appear in the early stages of muscle repair after injury yet to be answered.
Malformations of the Eye Resulting from Maternal Hypervitaminosis A during Gestation in the Rat
Authors: Padmanabhan R. , Singh Gurpreet , Singh Shamer
Published: July 2008

Vitamin A (1–1.5 lac IU) was administered orally to pregnant Wistar rats on days 8–14 of gestation (sperm + = day 0). Fetuses collected on day 21 revealed several anomalies including those of the eyes, e.g. open eyelids, exophthalmia, cataractous lens, microphthalmia and anophthalmia. Histological examination of treated eyes revealed degenerative changes in the cornea, lens and retina; shallowness or obliteration of anterior and vitreous chambers, and complete fusion of various structures with each other in some cases of microphthalmis. Anophthalmic cases showed no trace of any ocular structure. Retinae showed remarkable infoldings. The degenerative changes in retinae were associated with degeneration of optic nerve fibres. Eye malformations induced by hypervitaminosis A were stage dependent and mostly found in groups treated on day 8 and 9 of gestation. Reported cases of anomalies in humans associated with hypervitaminosis A during pregnancy warn us against the uncritical use of high doses of vitamin A during pregnancy.