bluuebunny/crossref_metadata_2025 huggingface dataset:
Elastic Fibers in the Anulus fibrosus of the Dog Intervertebral Disc
Authors: Johnson Eldridge F. , Caldwell Robert W. , Berryman Hugh E. , Miller Andrea , Chetty Kothapada
Published: July 2008

A light microscopic investigation of the anulus fibrosus in cervical intervertebral discs of the dog was conducted to ascertain the arrangement and distribution of elastic fibers. Elastic fibers were observed in all lamellae of the anulus fibrosus. However, collagenous fibers were the predominant type of connective tissue fiber, and elastic fibers were randomly dispersed among them. Intralamellar (collagenous and elastic) fibers were vertically and obliquely oriented in both superficial and deep lamellae of the anulus fibrosus. All intralamellar fibers were densely and regularly arranged in superficial lamellae, but they were more loosely organized in deep lamellae. A narrow border of interlamellar, elastic fibers was observed between broader, contiguous lamellae in the superficial zone of the anulus fibrosus. Interlamellar elastic fibers were vertically and obliquely arranged in superficial lamellae; however, they were radially oriented in deep lamellae. The deepest lamella of the anulus fibrosus consisted of a loose, three-dimensional network of intermeshing collagenous and elastic fibers. These observations suggest that elastic fibers are integral components of the articular and shock absorption mechanisms of the anulus fibrosus, and the cervical intervertebral disc of the dog is a suitable model for experimental investigation of the role of elastic fibers in intervertebral disc herniation.
Ultracytochemical Studies of Capillary Endothelial Cells in the Rat Central Nervous System
Authors: Inomata Kenichirou , Yoshioka Takafumi , Nasu Fumio , Mayahara Hiroshi
Published: July 2008

The ultracytochemical localization of eight hydrolytic enzymes (TMPase, 5’-NPase, TPPase, TTPase, Mg++-ATPase, Ca++-ATPase, ALPase and K+-NPPase) and one oxidative enzyme (MAO) was determined in rat brain capillary endothelial cells. In the somal plasma membrane, the enzymatic activity was mainly located in the antiluminal plasma membrane. This finding was appropriate for enzymes possessing the optimal pH at alkaline ranges, except for alkaline phosphatase. Most enzymes investigated showed a positive reaction on the pinocytotic vesicles of capillary endothelial cells. Differences in the intensity of the enzyme activities of the luminal and antiluminal plasma membranes may reflect the polarity in the capillary endothelial cells and relate to blood-brain barrier mechanisms.
Catecholamine-Containing Cells in the Nerve Plexus of the Guinea Pig Gallbladder
Authors: Cai Wen-Qin , Gabella Giorgio
Published: July 2008

A population of catecholamine-containing cells, broadly belonging to the class of small intensely fluorescent (SIF) cells, was observed in the ganglionated plexus and around blood vessels of the guinea pig gallbladder. Their morphological features were studied by fluorescence and electron microscopy. Some cells were closely associated with ganglion neurons within the ganglionated plexus. Others were clustered into small groups located along blood vessels. Counts carried out on the whole gallbladder showed that these cells varied greatly in number between individuals and that they were most numerous shortly after birth (on average 230 cells). In the adult, their average number was about 30.
The Surface of the Conjunctiva in Domestic Ruminants
Authors: Weyrauch K.D.
Published: July 2008

The surface of the conjunctiva was investigated in goats, sheep and bovines. The lid-facing surface of the nictitating membrane carries a serrated crest. At a low magnification the areas covered by a stratified squamous epithelium appear as a mosaic. In the superior and inferior conjunctival fornices the mucous membrane has a uniform appearance. Areas of goblet cells have an irregular appearance. Four functional stages can be observed in the goblet cells. At a high magnification the superficial cells of the palpebral and bulbar conjunctiva are covered by microplicae. In the fornix conjunctival microvilli project over the superficial cells.
Anatomy of the Knee Joint of the Cat
Authors: Prosé Poliacu
Published: July 2008

Based on dissection of 20 adult specimens the anatomy of the knee joint of the cat is described. An attempt is made to include all functionally relevant structures such as bones, ligaments, menisci, joint capsule and capsular reinforcements. A comparison with the human knee joint is made. There is a high resemblance in construction with the main differences occurring in the proportions of the constituent elements. A comparison of the semimembranosus and biceps femoris receives particular attention. These descriptions lead to functional considerations in relation to the stability and force transmission of the knee joint in the cat.
Distribution of Elastic System Fibers in Hyaline and Fibrous Cartilages of the Rat
Authors: Cotta-Pereira G. , Del-Caro L.M. , Monies G.S.
Published: July 2008

Rat hyaline and fibrous cartilages whose glycosaminoglycans had been removed by hyaluronidase digestion were studied by comparing the ultrastructural features with the observation of sections stained by selective methods for elastic system fibers under the light microscope. Except for the fibrous layer in the perichondrium of tracheal hyaline cartilage, where elastic fibers were found, no elastic fibers could be detected in the cartilages studied. However, cartilaginous tissues contained oxytalan and elaunin fibers. A distinct pattern of distribution of the above-mentioned elastic-related fibers could be observed in both kinds of cartilages. Hyaline cartilages possess oxytalan fibers in the extracellular matrix that surrounds the chondrocytes, whereas elastic fibers were localized in the fibrous layer of the perichondrium that encloses the cartilage. Elaunin fibers could be detected in the transition (chondrogenic) layer adjacent to the perichondrium. The methods used disclosed the presence of oxytalan and elaunin fibers running along the periphery of the collagen bundles in fibrocartilage.
Inhibitory Activity of Cartilage Growth in Serum of Young Rats
Authors: Kvinnsland Stener , Kvinnsland Steinar
Published: July 2008

Humoral factors play an important role in growth regulation. The growth regulatory activity in serum is a complex system with both growth-promoting and growth-inhibiting factors. In this study, using in vitro cartilage from rat nasal septum as target organ, evidence is presented that inhibiting activity does exist in normal rat serum. This activity seems to play a role in modulating cartilage growth rate in young, normal animals. Furthermore, a significant interaction between age in cartilage and age in serum as regards influence on cartilage growth was found.
Dissociated Cells from Different Layers of Adult Human Aortic Wall
Authors: Orekhov A.N. , Andreeva E.R. , Tertov V.V. , Krushinsky A.V.
Published: July 2008

Cells isolated from a fixed adult human aorta by alcoholic-alkaline dissociation retain their intrinsic shape. They are represented by four major morphological types: stellate, elongated, elongated with side processes, and irregularly shaped cells. All the four types of cells were found in the elastic-hyperplastic intimal sublayer; elongated and irregularly shaped cells were mainly observed in the musculoelastic sublayer and in the media. Cell density in the atherosclerotic lesion is higher than normal, the number of stellate cells being increased more substantially compared to other cell types. The origin of stellate cells and other morphological cell types, and reasons for their disproportionate accumulation in the atherosclerotic intima are discussed.
Effect of Ethylenediaminetetraacetic Acid on Postpartum Collagen Degradation: Collagen-Bound Collagenase
Authors: Shimizu Kiyoshi , Hokano Masami
Published: July 2008

Collagenase occurs in animal tissues in at least two molecular forms; free enzyme and collagen-bound enzyme. This study was undertaken to investigate which form is principal during the postpartum collagen degradation. Ethylenediaminetetraacetic acid, which depresses the calcium concentration in the serum, did not affect the postpartum collagen degradation. Histological study shows that the serum containing inhibitor such as α2-macro-globulin was widely scattered within the endometrium on the day of parturition. Since the calcium is necessary for collagenase to bind collagen and that the collagen-bound collagenase together with or without α1-macroglobulin is activated to a same level by protease, these results suggested the principal molecular form of collagenase during the postpartum involution is collagen-bound enzyme.
Karyokinetic Reactions in Rat Kidney Proximal Convoluted Segment Epithelium on Long-Term Lead Supply with Drinking Water
Authors: Duvenkamp A.
Published: July 2008

In the rat kidney proximal convoluted segment epithelium the development of intranuclear inclusion bodies was observed after long-term lead administration with the drinking water. The inclusion bodies were PAS-positive. By electron microscopy they were identified as composed of filaments and granules lacking any kind of surrounding membrane. During the experiment, the nuclear volumes increased commensurately with the duration of lead exposure. The nuclear volume increase was considered a physiological reaction since it began long before the first appearance of intranuclear inclusion bodies.
Ultrastructural Changes and Proliferation of Pituicytes in Mouse Posterior Lobe during Water Deprivation and Rehydration
Authors: Kawamoto Keiichi , Kawashima Seiichiro
Published: July 2008

Ultrastructural changes and proliferation of pituicytes during water deprivation and rehydration were studied in the posterior lobe of C57BL/Tw mice. Deprivation for 3 days brought about a significant increase in the number of electron-dense bodies (lysosomes) in pituicyte perikarya and their processes. The frequency of pituicytes enclosing neurosecretory axons in their cytoplasm significantly decreased as compared with that of the controls. 12-hour rehydration following deprivation for 3 days induced extensive development of rough endoplasmic reticulum and Golgi apparatus and an increase in frequency of neurosecretory axons enwrapped by pituicyte cytoplasm. However, at 2 days of rehydration the morphology of pituicytes was no more different from that of the controls. Mitotic figures of pituicytes were not encountered throughout the deprivation period of 6 days, but rehydration for 12 h and 1, 2, or 3 days following deprivation for 3 or 6 days was effective in eliciting an increase in mitotic activity. The present results indicate that pituicytes in the mouse posterior lobe are intimately related with the secretory mechanism of neurosecretory material from the neurosecretory axons and that the proliferation of pituicytes is stimulated in conditions of reaccumulation of neurosecretory material.
Investigation of Development, Structure and Function of the Phrenicocolic and Duodenal Suspensory Ligaments
Authors: van der Zypen E. , Révész E.
Published: July 2008

The development and structure of the duodenal suspensory ligament and the phrenicocolic ligament were studied in the human fetus, newborn and adult. The observations presented show that the superior retention band is transformed into the suspensory ligament of the duodenum. Within this ligament the muscle of Treitz develops. The inferior retention band atrophies. A new ligament, the phrenicocolic ligament, is formed in the fetal period of life. In this ligament, smooth muscle cells develop. The possible functions of the suspensory ligament of the duodenum and the phrenicocolic ligament are discussed.
Morphological Changes Induced in Mouse Mammary Gland by Porcine and Human Relaxin
Authors: Bani Gastone , Bigazzi Mario
Published: July 2008

The effects of pure porcine relaxin and of human decidual extracts with relaxin-like activity on the mammary gland of virgin mice primed with estrogen have been studied by the light microscope. Porcine relaxin enhanced the changes induced by estrogen alone; the effect was different in the various mammary tissues. In the stroma, relaxin only slightly increased the loosening of connective tissue, the extent of the adipose tissue and of the capillary bed, as well as the degranulation of the mast cells. The changes in the parenchyma, such as elongation and branching of ducts, are strikingly enhanced. Moreover, relaxin seems to promote differentiation of the cells forming the walls of distal ducts, and of the myoepithelial cells. Tissue extracts of human decidua with relaxin-like activity induce changes in the mammary gland similar to those due to porcine relaxin. Such data indicate that relaxin synergizes with estrogen to cause growth of ducts of the mammary gland and that tissue extracts of human decidua have a similar effect, thus providing further evidence that decidua may be a source of relaxin in humans.
Mast Cells in the Human Testis and Epididymis from Birth to Adulthood
Authors: Nistal Manuel , Santamaria Luis , Paniagua Ricardo
Published: July 2008

Mast cells are a constant cell-type in the connective tissues of the human testis and epididymis from birth to adulthood. Ultrastructural study shows that these cells are similar to those found in other connective tissues. Histometric studies revealed that the number of mast cells in the interstitium, mediastinum and albuginea of the testis as well as in the epididymal connective tissue increases slightly during infancy, decreases during childhood, and then increases again at puberty. Increases at puberty are particularly evident in both the testicular interstitium and the epididymis. During adulthood, the number of mast cells progressively decreases in all testicular and epididymal connective tissues. Changes in mast cell number may be related to changes observed in the development of testicular connective tissue which occurs primarily during infancy and puberty.
The Commissural Neurons of the Inferior Colliculus of the Rat
Authors: Herrera Manuel , Smith-Agreda Victor , Morera Constantino
Published: July 2008

During systematic observation of the cellular subnuclei of the inferior colliculus of adult rats, it was noted that in the zone of the intercollicular commissure, numerous neuronal perikaria appear intermingled between the commissural fibers. The neurons were studied using Golgi and TEM methods and classified according to their dendritic pattern in the isodendritic (15%), allodendritic (19%) and intermediate forms (66%) of neurons. A fourth neuronal group, situated between the commissure and the upper periventricular zone, is also in relation with the commissural fibers. The constancy of these neurons and their frequently axodendritic and axosomatic synapses suggest that they play an important role in the whole function of the commissure which, at present, is not well understood in spite of the number and distinct origin of their afferents.
Differentiation of Presumptive Lens Ectoderm of the Chick in vitro Studied with Immunofluorescence Techniques
Authors: Rahmani Tahereh M.-Z.
Published: July 2008

The differentiation capacity of presumptive lens ectoderm was studied in the chick by an in vitro technique using the appearance of central nervous system or lens-specific antigens as indicators of differentiation. Handling the explants resulted in ‘autodifferentiation’ of both antigens, but co-culture with alcohol-killed primitive node or optic cup material could induce much stronger differentiation. Little specificity exists in the reaction and a hypothesis is presented whereby selection between the two differentiation pathways is thought to be due mainly to maturation within the ectoderm and the inducing tissue plays a minor qualitative role.
Ontogenetic Study of the Hepatogastroesophageal Anastomotic Omental Veins
Authors: Nebot-Cegarra J. , Domènech-Mateu J.M.
Published: July 2008

The ontogenetic study of connections between the foregut venous plexus and the intrahepatic venous system through the omentum minus was studied. This study was performed in 20 embryos (6–30 mm crown-rump (CR) length) and 10 human fetuses (31–71 mm CR length). One or two anastomotic veins were observed in each of the 6–19 mm CR length embryos. These veins run through the cranial area of the omentum minus. Their enteric extremity is located at the level of the gastroesophageal junction while the hepatic extremity runs into the ductus venosus (9 cases), sinusoids of the left liver lobe (1 case), left branch of the portal vein (1 case) or into the subdiaphragmatic intervitelline anastomosis (1 case). The transient feature of anastomotic omental veins was enhanced, and its chronological relationship with the vena gastrica sinistra was analyzed in order to obtain an ontogenetic explanation to the uncommon adult cases which have been published.
Congenital Anomalies of the Ear Resulting from Cyclophosphamide Treatment in the Rat
Authors: Padmanabhan R. , Singh Shamer
Published: July 2008

A single dose of cyclophosphamide (20 mg/kg) administered on day 12 of gestation to CF rats resulted in microtia in 97.5% of fetuses at term. The ears of affected fetuses were low set and dorsally placed. Histological examination revealed persistence of meatal plug, branching of the primordium of external acoustic meatus, periotic hemorrhages, narrowing of tympanic cavity, presence of only one to two primordia of middle ear ossicles, hypoplasia of stapedial artery, a maximum of two turns of cochlea and under differentiation of the organ of Corti and the semicircular ducts. Hemorrhages in and around the region of the ear were extensive. Bilaterally symmetrical distribution of microtia and consistency of associated anomalies suggest that this is a good animal model for further investigation into the pathogenetic mechanisms of these ear anomalies.
Effects of Ovariectomy on the Ultrastructure of the Parathyroid Gland of the Golden Hamster
Authors: Emura Shoichí , Shoumura Shizuko , Ishizaki Noriko , Hayashi Kazuko , Iwasaki Yuji , Yamahira Tomo , Kitamura Yuzo , Isono Hideo
Published: July 2008

Ultrastructural changes of the parathyroid glands of ovariectomized golden hamsters were investigated. In the parathyroid glands there is a decrease in the area of each cell occupied by the Golgi complex, in the number of prosecretory granules and in the tortuosity of plasma membrane as compared with those of the control golden hamsters. In addition, the area occupied by lipid droplets appears to be increased and the number of secretory granules in the peripheral cytoplasm and large vacuolar body appears to be decreased compared to those of the control animals. These features suggest that the synthesis and release of parathyroid hormone may be suppressed in many chief cells of the ovariectomized golden hamsters.
Development of Blood Vessels in the Sympathetic Trunk Ganglia of the Chick Embryo during Their Histomorphogenesis
Authors: Ambrosi G. , Roncali L.
Published: July 2008

The development of the vascular patterns and the differentiation of the cellular components have been studied in the ganglia of the sympathetic trunk in chicken embryos from the 3rd to the 16th day of incubation. The time and the mode of formation of the extrinsic and intrinsic vascular networks seem to conform to the pattern of growth and differentiation of the nerve cells and to their distribution within the sympathetic ganglia.
Effect of the Removal of Different Endocrine Glands upon Insulin Secretion and B-Cell Ultrastructure
Authors: Dumm César L.A.Gómez , García María E. , Borelli María I. , Cortizo Ana Maria , de Gagliardino Elma E P. , Gagliardino Juan José
Published: July 2008

Glucose-induced insulin secretion and B-cell ultrastructure were studied in islets obtained from normal, adrenalectomized, radiothyroidectomized, ovariectomized and orchidectomized rats. Both parameters were also studied in the same experimental groups submitted to specific substitutive therapy. Insulin secretion in response to high glucose was significantly diminished in adrenalectomized, hypothyroid and male castrated rats. Conversely, this secretion was enhanced in ovariectomized rats. These abnormal insulin responses were restored to normal range by specific substitutive therapy. B-cell ultrastructure was markedly altered in hypothyroid and in female and male castrated rats. No significant changes were observed in the adrenalectomized rats. No conspicuous alterations were depicted in the other islet cell populations. The features of the morphological alterations were mainly related to changes in the B-granules and the rough endoplasmic reticulum. Modifications of the other B-cell organelles were less frequent. In the castrated rats, a distinctive feature was the appearance of a finely granulated colloid material. These B-cell alterations, consecutive to changes in the circulating levels of a given hormone, seemed to depend on the chemical structure of the hormone itself rather than on the changes induced in the B-cell secretory function. The ultrastructural changes described were reversed, as in the case of insulin release, by specific substitutive therapy. It is concluded that changes in the circulating levels of the hormones studied are followed by specific alterations in both B-cell secretion and ultrastructure.
Synthesis and Secretion of the Enamel Matrix Precursor by the Kitten Secretory Ameloblast
Authors: Sasaki Takahísa
Published: July 2008

Secretory ameloblasts in kitten molar tooth germs were examined with an electron microscope to analyze the synthesis and secretion processes of the enamel matrix precursor. The contents of the secretion granule were identified as fine granular material, which observed in both the rough endoplasmic reticulum and the Golgi cisterns, accumulated in the dilated margins of the innermost Golgi cistern and formed condensing vacuoles. The same kind of condensing vacuoles was also produced from the GERL cisterns. During the secretion granule maturation processes in the Golgi region, the contents accumulated densely and the granules grew smaller. In addition, granule-limiting membranes acquired fine, bristle coats. The mature secretion granules then migrated, along microtubules, into the surfaces of the Tomes processes and finally released their contents by a process of exocytosis at the type 1 face which faces the enamel growth region.
Frühe Veränderungen an der Prostata des Hundes nach Kastration
Authors: Sinowatz F.
Published: July 2008

Using electron microscopic techniques the prostate glands of male Beagle dogs were studied 3 days after castration. At this time marked differences in the extent of alterations of the glandular epithelium were observed: Whereas several acini showed only minor changes with reduction of epithelial height and diminution of secretory granules, many acini were severely affected with pronounced alteration of cellular structure and accumulation of large lipid droplets. A constant feature was the stimulation of the basal cells of the grandular epithelium. Additionally, in some areas of the gland aggregations of stimulated basal cells forming an acinus-like structure with a slit-like lumen were found. Our study shows that castration leads to marked alterations of prostatic epithelium within a short time. Androgen deprivation causes regressive changes of secretory epithelial cells, but clearly stimulates the basal cell population.
Effectiveness of Elastase with HCl Method for Cell Surface Visualization
Authors: Amemiya T.
Published: July 2008

Elastase was used with the HCl method to eliminate extracellular materials such as collagen, basal lamina and elastin for visualization of cell surfaces in the pecten capillary of the chick. The surfaces of the endothelial processes of the pecten capillary were revealed more beautifully by scanning electron microscopy when elastase was applied following HCl treatment than when the HCl-collagenase method was used. In addition, elastase could shorten the incubation time of HCl.
Arterial Component of the Angioarchitecture of the Canine Ovary
Authors: Esperança-Pina J.A. , Reis Ana Maria
Published: July 2008

In order to study and possibly identify a vascular pattern in the canine ovary, 30 ovarian specimens received arterial injections of a mixture of ‘Micropaque’ with hydrosoluble red pigment, followed by clearing. The aorta or the femural artery was catheterized and the injection was performed under a constant pressure of 120 mm Hg. The blood supply of the ovary is provided by the ovarian and the uterine artery. The former appears to be the most important of the two arteries since it is the largest and is the origin of a very rich vascular net in the ovarian stroma. It follows a helicine course within the broad ligament and enters into the ovarian stroma either by a single trunk or by two divergent branches, each supplying the anterior and the posterior half. When there is only a single trunk, one can see a vascular tuft totally occupying the stroma, with tortuosities running in the same direction as the longitudinal axis of the ovary. When there are two branches, the distribution is similar but with two tufts instead of one. From the ovarian artery several branches arise, the largest and most frequent being the lateral tubal artery and a branch which anastomoses with the uterine artery in the mesovarium. Other branches anastomose with one another or with branches of the uterine artery, forming a rich vascular net along the mesovarium. The uterine artery is situated within the broad ligament and runs along the lateral border of the uterus and up to the superior extremity of the uterus where it ends. Two of the collateral branches are constantly in relation with the ovarian blood supply. One of them enters into the ovary at its superior pole and the other anastomoses with the ovarian artery within the mesovarium. The two vascular pedicles were anastomosed by one vessel of a smaller caliber that rarely exceeded 400 µm in 28 cases (93.33%) corresponding to type II At in 3 cases (10%) and type II A2 in 25 cases (83.33%). The two pedicles were not found anastomosed in 2 cases (6.66%) corresponding to type II B. Types I, III and IV of the Mocquot and Rouvillois classification were not found in the female dog ovary.
The Muscle Layer of the Canine Gallbladder and Cystic Duct
Authors: MacPherson B.R. , Scott G.W. , Chansouria J.P.N. , Fisher A.W.F.
Published: July 2008

The muscle layer of the canine gallbladder wall and cystic duct was found to be a three-dimensional meshwork of smooth muscle bundles which appear loosely and irregularly arranged on the mucosal aspect and consolidate to form a homogeneous plate-like layer on the serosal aspect. The muscle bundles are tightly woven around interspersed pockets of loose connective tissue in the gallbladder wall and gradually become loosely arranged with more prominent amounts of intervening connective tissue in the cystic duct. The muscle layer is thickest in the gallbladder wall and becomes progressively thinner out into the cystic duct. No anatomic sphincter was observed. Ultrastructural organization revealed individual muscle fibers to be of irregular profile, often branching, widely spaced with intervening collagen fibers, and having few cell-to-cell contacts.
Contacts between Wolffian and Müllerian Cells at the Tip of the Outgrowing Müllerian Duct in Rat Embryos
Authors: Dohr Gottfried , Tarmann Therese
Published: July 2008

The developing Müllerian duct was studied at the light microscopic as well as the electron microscopic level in rat embryos, especially in the section of the terminal bud and its tip, where Wolffian and Müllerian duct are enclosed by a common basal membrane. In this zone desmosomes can be found among Wolffian cells and also among Müllerian cells. In addition, we found cell contacts between Müllerian and Wolffian cells, namely short electron-dense segments on adjacent surfaces or disc-shaped thickenings within opposite plasma membranes, as well as fusions of the plasmalemmata over short distances. Until now, these cell contacts have not been described in rat embryos.
Effect of Sulpiride on the Adenohypophysis of Castrated Male Rats
Authors: Pérez Ricardo L. , von Lawzewitsch Irene
Published: July 2008

Previous studies have shown that N-[(1-ethyl-2-pyrrolidinyl)methyl])-2-methoxy-5-sulfamoylbenzamide (sulpiride), a psychotrophic drug of clinical use, is a potent antidopaminergic agent, and acts on prolactin and gonadotroph secretions. Cytological changes caused by the effects of this drug were studied in castrated male rats treated with daily doses of sulpiride 5 mg/100 g body weight. Animals were sacrificed 2 months after treatment and their hypophyses processed for cytological and immunohistochemical studies. Cytomorphometry was carried out at the ultrastructural level. An immunocytochemical study was performed with peroxidase-labelled antibody to determine PRL, FSH and LH hormones in gland sections. The administration of sulpiride produced a decrease in granules of prolactin cells. Only the Golgi region showed a positive prolactin reaction and the cytomorphometric study indicated an increase of the area occupied by the endoplasmic reticulum and Golgi complex. In gonadotrophs, treatment with sulpiride decreased the vacuolatin caused by castration. The area occupied by the endoplasmic reticulum was smaller, whereas that occupied by secretion granules and lysosomes became larger. It is suggested that sulpiride treatment increased markedly the mammotroph activity and decreased the gonadotroph one, restoring the vacuolation of the endoplasmic reticulum vacuolation to normal.
Immunocytochemical Study on the C Cells in Pig Thyroid Glands
Authors: Tsuchiya T. , Shiomura Y. , Suzuki K. , Nagai H. , Tamate H.
Published: July 2008

The distribution of pig thyroid C cells was demonstrated by a immunoperoxidase method using antiserum to porcine calcitonin. The average number of C cells per 4 mm2 counted in the deep and superficial regions was 127 and 55, respectively. The number in the cranial, middle and caudal regions was 60, 128 and 83, respectively. The number of C cells per follicular and C cells (C cell concentration) in deep and superficial regions was 4.9 and 2.6%. It was 3.2, 4.9 and 3.3% in the cranial, middle and caudal regions, respectively. These results indicate that the number and concentration of C cells were not only larger in deep than superficial regions but also in the middle region than in cranial and caudal in pig thyroid gland. These results also indicate that the C cell distribution in pig thyroid gland is the same as that of dog, human, cat, rat, guinea pig, and mouse.
Resorption of Endometrial Collagen in Oophorectomized Rats
Authors: de Jesus Simões Manuel , Alves Mora Osvaldo , Oliveira-Filho Ricardo M.
Published: July 2008

Uteri of rats that had been either oophorectomized or given a single dose of 17β-diethylstilbestrol or progesterone were studied as to the ultrastructural features of collagen resorption by the fibroblasts of the endometrial stroma. Electron microscopy showed several cytoplasmic vesicles within fibroblasts containing collagenous fibrils in various stages of breakdown. These findings suggest that fibroblasts have a collagenolytic action. Hence, this cell type may play a dual role in the metabolism of endometrial collagen – firstly being responsible for its synthesis, and secondly participating in its resorption.
Histochemical Fiber Composition of Lumbar Back Muscles in the Rabbit
Authors: McFadden K.D. , Bagnall K.M. , Mahon M. , Ford D.
Published: July 2008

The present study of the back muscles of the rabbit, using enzyme histochemical techniques and stereological methods, was undertaken with the view to gaining a better understanding of the fiber-type make-up of the lumbar musculature of this animal. The muscles considered were the multifidus, sacrospinalis and the intertransversarii between levels L5 and L6. Gross examination reveals that the multifidus and the sacrospinalis form the bulk of the lumbar musculature and that these muscles appear white. -Between and deep to these two muscles are the red intertransversarii. Histochemically the multifidus and the sacrospinalis are also similar in their fiber-type composition, mostly types IIA and IIB and the percentage of connective tissue that they contain. The intertransversarii, in contrast, are for all practical purposes composed of only type-I fibers. The intertransversarii contain significantly more connective tissue than the other two muscles. It may be concluded that the bulk of the lumbar musculature of the rabbit is phasic while the intertransversarii, containing only type-I fibers and a high percentage of connective tissue, are postural muscles.
Effect of Guanethidine-Induced Sympathectomy on Osteoblastic Activity in the Rat Femur Evaluated by 3H·Proline Autoradiography
Authors: Herskovits Mark S. , Singh Inder Jit
Published: July 2008

Osteoblastic activity in the rat femur was assessed following sympathectomy by injections of guanethidine sulfate from birth to 14 days of age. At ages 30, 45 and 90 days, osteogenesis was monitored by quantitative autoradiography using 3H-proline. Grain counts over periosteal osteoblasts of the femoral diaphysis showed a significant reduction in the uptake of 3H -proline in sympathectomized rats. The results indicate that the sympathetic innervation of bone influences osteoblastic activity and provide support for a role of the autonomic nervous system in the regulation of bone formation.
Morphological Characterization of Stationary Reticulum Cells of the Stromal in the Mesenteric Lymph Node of the Guinea Pig
Authors: Severi B. , Biagini G. , Govoni E. , Artusi T. , Federico M. , De Pasquale A. , Bottanelli P. , Franchini M. , Milanesi S.
Published: July 2008

The large mesenteric lymph node taken from guinea pigs in a period of time ranging from the 10th day prepartum till the 26th day postpartum has been examined in order to study: (i) the morphological features of the stromal stationary reticulum cells with particular regard to recognize their stages of development; (ii) the possible ontogenetic relationship between these cells during the maturation of the lymphoid tissue. Our data support the hypothesis that from local mesenchymal cells originates a pool of poorly differentiated reticulum cells that can give rise to stromal stationary reticulum cells (myofibroblast-like cells, fibroblast-like cells, pericyte-like cells and dendritic cells). These elements have a characteristic distribution pattern likely related to different local functional requirements.
Effect of Maternal Dietary Fat on Skeletal Muscle Cellularity and Satellite Cell Content of the Porcine Fetus at 110 Days of Gestation
Authors: Campion Dennis R. , Seerley Robert W. , Kveragas Cindy L.
Published: July 2008

Crossbred gilts and sows were fed isocaloric diets that contained 0, 2.3, 12.8 or 29.7% poultry fat beginning at day 80 of gestation. At day 110 of gestation, fetuses were removed by Caesarean section. Maternal dietary fat did not influence fetal weight, sartorius muscle weight, length, composition, cellularity or satellite cell content. It was concluded that feeding diets high in fat during the last trisemester as exercised in this study did not influence the satellite cell content or cellularity of skeletal muscle.
Effects of Pituitary Grafting and CB-154 Treatment on the Growth of Prostates in Mice
Authors: Mori T. , Nagasawa H.
Published: July 2008

Implantation of a single anterior pituitary into the ventral prostates of intact mice induced a significant increase in the weight and the area occupied by the glands of ventral prostates associated with the elevation of circulating prolactin. However, the growth of the dorsolateral prostates was not augmented by the treatment. Injection of CB-154 (bromocriptine-mesilate) during the developmental stage of the prostatic tissue (3–5 weeks of age) suppressed the weight increase of ventral prostates but not dorsolateral prostates in intact mice. All results suggest the different response of the ventral and the dorsolateral prostates to prolactin. Pituitary grafting produced hyperplastic lesions in the prostates, however, modified little the effects of carcinogen on the tissue.
Ultrastructural Peculiarities of the Inner Portion of the Circular Layer of Colon. I.
Authors: Faussone Pellegrini Maria Simonetta , Cortesini C.
Published: July 2008

The inner part of the circular layer of the human colon is made up of a special muscle layer, three to eight rows thick. Wide areas of connective tissue are found inside this inner circular layer and between it and the outer part of the circular layer. The muscle cells of this innermost layer have several special features: numerous glycogen particles and caveolae, well-developed sarcoplasmic reticulum, and wide contact areas with each other. At the border zone with the tela submucosa, there is a fibrous lamella rich in collagen and elastic fibers, lined by an incomplete layer of circularly orientated fibroblast-like cells. A nerve plexus, rich in varicosities, is located between the two circular layers, and nerve fibers are sparsely located inside the fibrous lamella. Interstitial cells of Cajal were not recognized.
Architecture of the Corneal Stroma of the Hen
Authors: Lucio Aldiva , Smith Ricardo Luiz
Published: July 2008

The corneal stroma architecture was studied in the adult chicken. Utilizing gross preparations, light and electron microscopic observations, the authors described the stromal lamellar arrangement. The stroma consists of two systems of lamellae: (1) a superficial or subepithelial system, formed by fan like spreading lamellae disposed in a spiral fashion localized at the superficial one fourth of the stroma and through the whole cornea, and (2) a deep system formed by an orthogonal gridwork of lamellae. Both systems are continuous.
Light Microscopic Study of Blood Vessels of the Nasal Cavity of the Pig
Authors: Ghoshal N.G. , Khamas W.A.H.
Published: July 2008

4 adult pigs were used for light microscopic studies to depict the relationship between nasal blood vessels and the surface epithelium, and to describe the histomorphology of these vessels. After giving an electric shock, animals were bled to death. Tissues were collected from three regions in the nasal cavity after splitting heads sagittally. Different types of vessels were described and a new classification was suggested. Arteries were muscular in type with, as well as without, internal elastic laminae. Thick-alled veins (characterized by smooth muscle cells in the tunica media) were present throughout the nasal cavity, while thin-walled veins or cavernous spaces were discernible only in the caudal one third of the nasal cavity. Further, arteriovenous anastomoses, epithelioid arterioles, and free smooth muscle cells in the propria submucosa were observed throughout the nasal cavity.
Degradation of Annular Gap Junctions of the Equine Hoof Wall
Authors: Leach D.H. , Oliphant L.W.
Published: July 2008

Annular gap junctions interiorized within cells of the stratum spinosum of the coronary border of the equine hoof were degraded by two methods. Some were autophagocytized and some appeared to fuse with lysosomes to form heterophagosomes. Structural changes of partially degraded annular gap junctions included increased density of the enclosed cytoplasm, formation of filamentous or membrane-like material within the annular gap junction, and disruption of the circular or oval profile of the gap junction. The annular gap junctions are apparently incorporated into the fully keratinized cells of the stratum corneum.
Innervation Pattern of Intrinsic Laryngeal Musculature of the Rabbit
Authors: Cecio A. , Avitabile G. , Langella M.
Published: July 2008

The intrinsic laryngeal musculature of rabbit was studied using various neurohistological techniques. The vegetative and sensory nerve terminals are present in abundance, while the proprioceptors are seemingly absent. Furthermore, simple motor endplates, sometimes furnished with ultraexpansional fibers, complex end-plates, or ‘en grappe’ are described. Their abundance within a musculature lacking in muscle-spindles is indicative of a possible vicarious function.
Myeloperoxidase Delays Neutrophil Apoptosis Through CD11b/CD18 Integrins and Prolongs Inflammation
Authors: El Kebir Driss , József Levente , Pan Wanling , Filep János G.
Published: July 2008

Polymorphonuclear neutrophil granulocytes have a central role in innate immunity and their programmed cell death and removal are critical for efficient resolution of acute inflammation. Myeloperoxidase (MPO), a heme protein abundantly expressed in neutrophils, is generally associated with killing of bacteria and oxidative tissue injury. Because MPO also binds to neutrophils, we investigated whether MPO could affect the lifespan of neutrophils. Here, we report that MPO independent of its catalytic activity through signaling via the adhesion molecule CD11b/CD18 rescued human neutrophils from constitutive apoptosis and prolonged their life span. MPO evoked a transient concurrent activation of extracellular signal-regulated kinase and Akt, leading to phosphorylation of Bad at both Ser112 and Ser136, prevention of mitochondrial dysfunction, and subsequent activation of caspase-3. Consistently, pharmacological inhibition of extracellular signal-regulated kinase, Akt, or caspase-3 reversed the antiapoptosis action of MPO. Acute increases in plasma MPO delayed murine neutrophil apoptosis assayed ex vivo. In a mouse model of self-resolving inflammation, MPO also prolonged the duration of carrageenan-induced acute lung injury, as evidenced by enhanced alveolar permeability and accumulation of neutrophils parallel with suppression of neutrophil apoptosis. Our results indicate that MPO functions as a survival signal for neutrophils and thereby contribute to prolongation of inflammation.
Absence of Hyperlipidemia in LDL Receptor-Deficient Mice Having Apolipoprotein B100 Without the Putative Receptor-Binding Sequences
Authors: Johnson Lance A. , Altenburg Michael K. , Walzem Rosemary L. , Scanga Lori T. , Maeda Nobuyo
Published: July 2008

Objective—

To examine the effects of apoB100 structure, specifically a mutation in the LDLr binding region, on the production of LDL and development of atherosclerosis in vivo.

Methods and Results—

Ldlr
−/−
Apobec1
−/−
mice lacking the LDLR and apoB editing enzyme accumulated LDL in plasma and developed severe atherosclerosis when they had wild-type apoB100. In marked contrast, in
Ldlr
−/−
Apobec1
−/−
mice carrying the Apob100-β mutation, in the 2 putative LDLR-binding domains of apoB prevented both LDL accumulation and atherosclerosis. Intestinal absorption of lipids and triglyceride secretion from the liver were not affected. However, the VLDL particles with apoB100-β were larger in volume by about 70%, and carried approximately four times as much apoE per particle. ApoB100-β synthesis rate in the primary hepatocytes was normal, but its intracellular degradation was enhanced. Additionally, mutant apoB100 VLDL cleared from the circulation more quickly in vivo through apoE-LRP-mediated mechanism than VLDL with wild-type apoB100. In contrast, uptake of the 2 VLDL by macrophages were not different.

Conclusion—

While conformational change to apoB100 during conversion of VLDL to LDL exposes LDLR binding domains and facilitates LDLR-mediated lipoprotein clearance, it may also inhibit LRP-mediated VLDL uptake and contribute to LDL accumulation in familial hypercholesterolemia.
Brief Report: Accelerated Atherosclerosis in Low-Density Lipoprotein Receptor-Deficient Mice Lacking the Membrane-Bound Complement Regulator CD59
Authors: Yun Sheng , Leung Viola W.Y. , Botto Marina , Boyle Joseph J. , Haskard Dorian O.
Published: July 2008

Objective—

Whereas studies in humans and animal models have suggested a role for complement activation in atherosclerosis, there has been little analysis of the importance of complement regulators. We tested the hypothesis that the terminal pathway inhibitor CD59 plays an essential role in limiting the proinflammatory effects of complement activation.

Methods and Results—

CD59 gene targeted mice (
CD59a
−/−
) mice were crossed with low-density lipoprotein receptor-deficient (
Ldlr
−/−
) mice. CD59-deficient
Ldlr
−/−
mice had significantly more extensive en face Sudan IV staining of thoracoabdominal aorta than
Ldlr
−/−
single knock-outs, both after a low-fat diet (6.51±0.36% versus 2.63±0.56%,
P
<0.001) or a high-fat diet (17.05±2.15% versus 7.69±1.17%,
P
<0.004). Accelerated lesion formation in
CD59a
−/−
/
Ldlr
−/−
mice on a high-fat diet was associated with increased lesional vascular smooth muscle cell (VSMC) number and fibrous cap formation.

Conclusion—

Our data show that CD59 deficiency accelerates the development of lesions and increases plaque VSMC composition. Assuming that the main function of CD59 is to prevent the development of C5b-9 membrane attack complexes, our observations are consistent with the terminal complement pathway having proatherogenic potential in the
Ldlr
−/−
mouse model, and highlight the importance of complement regulation.
Macrophages and Platelets Are the Major Source of Protease Nexin-1 in Human Atherosclerotic Plaque
Authors: Mansilla Silvana , Boulaftali Yacine , Venisse Laurence , Arocas Véronique , Meilhac Olivier , Michel Jean-Baptiste , Jandrot-Perrus Martine , Bouton Marie-Christine
Published: July 2008

Objective—

Protease nexin-1 (PN-1), a serpin constitutively expressed by vascular smooth muscle cells and endothelial cells, inhibits thrombin, plasminogen activators, and plasmin and can thus be expected to play a role in vascular biology. The present study addressed the question of PN-1 expression in human atherothrombosis.

Methods and Results—

Immunohistochemistry and biochemical studies confirmed that PN-1 was expressed at a moderate level in the medial layer of normal human arteries and showed that PN-1 expression was increased in atherothrombotic lesions. In early noncomplicated plaques, PN-1 was associated with infiltrating mononuclear cells. A strong PN-1 signal was observed in advanced lesions, principally in intraplaque hemorrhage-related structures. Monocytes/macrophages and platelets were identified as the main sources of PN-1 within atherothrombotic material. Isolated human monocytes and platelets both expressed high levels of active PN-1, and monocyte PN-1 expression was upregulated, at both messenger and protein levels, in response to stimulation by lipopolysaccharides. In contrast, PN-1 expression was downregulated during their differentiation into macrophages which were shown to produce degraded forms of PN-1.

Conclusions—

Platelets and monocytes/macrophages are a major source of PN-1 in human atherothrombotic plaques. PN-1 could thus represent a new actor in the evolution of atherosclerotic lesions.