bluuebunny/crossref_metadata_2025_split huggingface dataset:
Covalent affinity labeling, radioautography, and immunocytochemistry localize the glucocorticoid receptor in rat testicular leydig cells
Authors: Stalker Alison , Hermo Louis , Antakly Tony 
Published: February 2005

AbstractThe presence and distribution of glucocorticoid receptors in the rat testis were examined by using 2 approaches: in vivo quantitative radioautography and immunocytochemistry. Radioautographic localization was made possible through the availability of a glucocorticoid receptor affinity label, dexamethasone 21‐mesylate, which binds covalently to the glucocorticoid receptor, thereby preventing dissociation of the steroid‐receptor complex. Adrenalectomized adult rats were injected with a tritiated (3H) form of this steroid into the testis and the tissue was processed for light‐microscope radioautography. Silver grains were observed primarily over the Leydig cells of the interstitial space and to a lesser extent, over the cellular layers which make up the seminiferous epithelium, with no one cell type showing preferential labeling. To determine the specificity of the labeling, a 25‐ or 50‐fold excess of unlabeled dexamethasone was injected simultaneously with the same dose of (3H)‐dexamethasone 21‐mesylate. In these control experiments, a marked reduction in label intensity was noted over the Leydig as well as tubular cells. Endocytic macrophages of the interstitium were non‐specifically labeled, indicating uptake of the ligand possibly by fluid‐phase endocytosis. A quantitative analysis of the label confirmed the presence of statistically significant numbers of specific binding sites for glucocorticoids in both Leydig cells and the cellular layers of the seminiferous epithelium; 86% of the label was found over Leydig cells, and only 14% over the cells of the seminiferous epithelium. These binding data were confirmed by light‐microscope immunocytochemistry using a monoclonal antibody to the glucocorticoid receptor. Intense immunocytochemical staining was seen predominantly in the cytoplasm of the Leydig cells, whereas the cells of the seminiferous epithelium were weakly stained. Thus, the present data reveal a high glucocorticoid receptor content within Leydig cells and a lower level within cells of the seminiferous epithelium. Furthermore, the present experiments demonstrate for the first time the usefulness of dexamethasone 21‐mesylate as an affinity label for the morphological localization of the glucocorticoid receptor. The localization of glucocorticoid receptors in Leydig cells suggest a role for this steroid in regulating the function of these cells.
Innervation of the renal proximal convoluted tubule of the rat
Authors: Barajas Luciano , Powers Kenneth 
Published: February 2005

AbstractExperimental data suggest the proximal tubule as a major site of neurogenic influence on tubular function. The functional and anatomical axial heterogeneity of the proximal tubule prompted this study of the distribution of innervation sites along the early, mid, and late proximal convoluted tubule (PCT) of the rat. Serial section autoradiograms, with tritiated norepinephrine serving as a marker for monoaminergic nerves, were used in this study. Freehand clay models and graphic reconstructions of proximal tubules permitted a rough estimation of the location of the innervation sites along the PCT. In the subcapsular nephrons, the early PCT (first third) was devoid of innervation sites with most of the innervation occurring in the mid (middle third) and in the late (last third) PCT. Innervation sites were found in the early PCT in nephrons located deeper in the cortex. In juxtamedullary nephrons, innervation sites could be observed on the PCT as it left the glomerulus. This gradient of PCT innervation can be explained by the different tubulovascular relationships of nephrons at different levels of the cortex. The absence of innervation sites in the early PCT of subcapsular nephrons suggests that any influence of the renal nerves on the early PCT might be due to an effect of neurotransmitter released from renal nerves reaching the early PCT via the interstitium and/or capillaries.
Crypt base columnar cells in ileum of BDF1 Male Mice—their numbers and some features of their proliferation
Authors: Chwalinski S. , Potten C. S. 
Published: February 2005

AbstractSome features of the proliferative cells at the bottom of the ileal crypts in BDF1 mice have been studied in relation to the distribution of Paneth cells (PC) in an attempt to clarify the nature and function of these crypt base columnar cells (BCC) and to elucidate some aspects of the role of the microenvironment created by the PC.Longitudinal sections of crypts have shown that the ratio of PC to the BCC, which are scattered amongst the PC, is 2.7:1 in sections or approximately 29 PC and 9 BCC per whole crypt, i.e., a ratio of 3.2:1. The labelling index of BCC is about 35%, which is comparable to that of mid‐crypt columnar cells. Although the BCC do become labeled, it is concluded that they cannot create vertical pairs or runs of several adjacent BCC since this would seriously disturb the distribution of Paneth cells. Only in dividing crypts are such runs (consisting of 3 to 5 cells) observed. The ability of BCC to synthesize DNA is not dependent on their position in the Paneth cell zone. In 95% of the crypts, the highest Paneth cell is below the 7th cell position from the bottom of the crypt, and the positions of the highest PC on either side of a given crypt are similar. The secreted granules or the cytoplasm of PC specifically bind pokeweed lectin, and this can be used for identification.Tracer doses of 3HTdR (37 kBq/gm body weight) result in the histological death of some BCC, and these damaged cells are evenly distributed throughout the Paneth cell zone. These tracer doses are somewhat selectively incorporated into BCC, i.e., the BCC have a higher grain count in autoradiographs, probably because they possess more thymidine kinase enzyme activity. This ability is very sensitive to the withdrawal of food, because 24 hr of fasting abolished the observed gradient in the intensity of labelling, which is very well correlated with the distribution of BCC.Regeneration of the crypts following cytotoxic exposure to Ara‐C is initiated at the base of the crypt and hence may involve the BCC with possible help from the Paneth cells. The latter are insensitive to cytotoxic (S phase specific) agents and may help in the regeneration by preserving the architecture of the base of the crypt.
Fine structure of the dorsal lingual epithelium of the lizard, Gekko japonicus (Lacertilia, Gekkonidae)
Authors: Iwasaki S. 
Published: February 2005

AbstractThree different types of lingual papilla were observed by scanning electron microscopy on the dorsal lingual epithelium of the lizard Gekko japonicus. Dome‐shaped lingual papillae were located at the apex. Flat, fan‐shaped lingual papillae were seen in the widest area of the lingual body. Long, scale‐like lingual papillae were arranged on the latero‐posterior dorsal surface. At higher magnification, microvilli and microridges were seen to be widely distributed over the surface of the papillae. By light microscopy, the epithelium of the dome‐shaped papillae was composed of single, columnar epithelial cells filled with secretory granules. The tip of the epithelium of the fan‐shaped and scale‐like papillae was composed of stratified squamous epithelial cells without granules. The major part of the epithelium of these two types of papilla, except the tip area, was also composed of single, columnar epithelial cells with secretory granules. By transmission electron microscopy, a nucleus without a defined shape was seen to be located in the basal part of each of the single, columnar epithelial cells. Rough‐surfaced endoplasmic reticulum and Golgi apparatus were well developed around the nucleus. The other, major part of the cytoplasm was filled with the spherical secretory granules, a large number of which had very electron‐dense cores and moderately electron‐dense peripheral regions. In the stratified squamous epithelium, a nucleus, which tended to be condensed on the free‐surface side, was located in the center of each cell. Mitochondria, endoplasmic reticulum, and vesicles were observed in the cytoplasm.
Ultrastructural features of mitochondria‐rich cells in stenohaline freshwater and seawater fishes
Authors: Pisam M. , Boeuf G. , Prunet P. , Rambourg A. 
Published: February 2005

AbstractIn order to elucidate the functional significance of accessory cells in freshwater fishes, such as the rainbow trout, which displays a poor adaptability to seawater life, a search for such cells was performed in two stenohaline freshwater fishes: the loach and the gudgeon. Accessory cells were never encountered in these species; but, in contrast, two types of chloride cells were observed consistently that strikingly resembled the α‐ and β‐cells previously described in the guppy, a freshwater‐adapted euryhaline fish. The α‐cell, a pale and elongated chloride cell, was located at the base of the secondary lamellae in close contact with the arterioarterial pillar capillary. Darker, ovoid chloride cells resembling the β‐cell were found exclusively in the interlamellar region of the primary epithelium facing the central venous sinous. The latter cells frequently formed multicellular complexes linked together by deep, narrow, apical junctions.In another experiment, a stenohaline seawater fish, the turbot, was adapted to diluted 5% saltwater and to fresh water. In seawater, the gill epithelium contained only one type of chloride cell, always associated with accessory cells. Due to numerous cytoplasmic interdigitations between the accessory cells and the apical portion of the chloride cell, there was a noticeable increase in the length of the shallow apical junction, sealing off the intercellular space between the two cell types. In 5% saltwater, there was a decrease in the number of these interdigitations and a concomitant decrease in the length of the shallow apical junction. In fresh water, chloride cells were partially or completely separated from the outside medium by modified accessory cells.It is thus concluded that accessory cells are found exclusively in fish living in seawater or preadapted to seawater and that they probably are involved in the formation and modulation of paracellular pathways for ionic excretion. In contrast, the respective roles of the two types of chloride cells observed in freshwater fishes are still to be determined.
Effect of photoperiod on pineal gland volume and pinealocyte size in the chinese hamster, Cricetulus griseus
Authors: Matsushima Shoji , Sakai Yuko , Hira Yoshiki 
Published: February 2005

AbstractMale adult (200‐day‐old) Chinese hamsters (Cricetulus griseus) raised from weaning under either LD 16:8 or LD 8:16 were used. The pineal gland of the Chinese hamster consists of superficial (major) and deep (minor) components and a continuous, or interrupted, narrow parenchymal stalk interposed between them. The volume of the superficial pineal including the parenchymal stalk is greater under LD 16:8 than under LD 8:16. Under both photoperiods, pinealocytes in the superficial pineal have larger nuclei and more abundant cytoplasm than those in the deep pineal. Nuclei in the superficial pineal appear pale and usually have irregular profiles, whereas those in the deep pineal appear dark and have round profiles. In the superficial pineal, pinealocyte nuclei are larger, paler, and more irregular; and, in addition, nuclear density is lower under LD 16:8 than under LD 8:16. Similar, but less prominent, photoperiod‐induced changes occur in the volume of the deep pineal, the size of pinealocytes, and pinealocyte nuclear morphology in the deep pineal. The results indicate that the development and differentiation of pinealocytes in both pineal portions may be advanced under long photoperiods and delayed under short photoperiods, although pinealocytes in the deep pineal may remain not fully differentiated even in adults. Since testicular weights and body weights are similar under both photoperiods, the photoperiod may exert marked influences on the development of the pineal gland without affecting reproductive activity and growth rates of animals.
Comparative distribution of carbonic anhydrase isozymes III and II in rodent tissues
Authors: Spicer Samuel S. , Ge Zhen‐Hau , Tashian Richard E. , Hazen‐Martin Debra J. , Schulte Bradley A. 
Published: February 2005

AbstractCarbonic anhydrase (CA) III was demonstrated immunocytochemically in epithelium in some regions of salivary gland ducts, colon, bronchi, and male genital tract and in adipocytes, in addition to skeletal muscle and liver where the isozyme was previously localized. Basal cells beneath the submandibular gland's excretory ducts in guinea pig stained for CA III. Carbonic anhydrase III occurred alone in some and with CA II in other sites but was often absent from CA‐II‐containing types of cells. This was exemplified by CA III's abundance in CA‐II‐positive proximal colon and its sparsity in the CA‐II‐rich distal colon of the mouse. Striated ducts in guinea pig, but not mouse salivary glands, stained darker for CA and appeared accordingly to function more actively in ion transport compared with excretory ducts. Carbonic anhydrase content varied among genera in liver and pancreas and between mouse species and strains in salivary glands and kidney. Newly observed murine sites of CA II activity included Auerbach's plexus and a population of leukocytes infiltrating the lamina propria in small intestine, and several types of cells in the male genital tract. In immunoblot tests, antisera to CA III showed no cross reactivity with antisera to CA II, but those to CA II disclosed weak cross reactivity with CA III.
Oviductal epithelium of the baboon: Hormonal control and the immuno‐gold localization of oviduct‐specific glycoproteins
Authors: Verhage Harold G. , Mavrogianis Patricia A. , Boice Melinda L. , Li Weiguo , Fazleabas Asgerally T. 
Published: February 2005

AbstractOviducts were obtained from a series of cycling and ovariectomized steroidtreated baboons. The lining epithelium of the ampulla and isthmus was analyzed by light and electron microscopy. Both morphological and cytomorphometric analyses revealed that the morphological and functional state of the oviductal epithelium in the baboon is controlled by the ovarian steroids. Additionally, a clear cephalocaudal steroid‐responsive gradient was observed when the data from the ampulla and isthmus of the same animal were compared. Within the ampulla, estradiol induced hypertrophy, hyperplasia, ciliogenesis, and secretory activity, whereas adding progesterone to the treatment regimen (± estradiol) resulted in atrophy, deciliation, apoptosis, and loss of the secretory activity. These cyclic processes were less evident in the isthmus. We also used an indirect electron microscopic immunogold technique and a previously characterized polyclonal antibody to determine the localization of oviduct‐specific glycoproteins. These glycoproteins were present in every secretory granule observed, regardless of oviduct region, electron density, or size of the secretory granule. In summary, our data show that (1) estradiol induces and maintains the mature epithelium of the baboon oviduct, (2) steroid withdrawal or the administration of progesterone causes regression of the epithelium, and (3) the previously identified estradiol‐dependent oviduct‐specific glycoproteins are synthesized within and released from the secretory epithelial cells.
Effect of altered occlusal function on transseptal ligament and new bone thicknesses in the periodontium of the rat
Authors: Johnson Roger B. 
Published: February 2005

AbstractAlteration of tooth function is assumed to change stress/strain on the adjacent alveolar bone and its mucoperiosteum, producing changes in morphology similar to those described for other load‐bearing bones. The present study suggested that crestal alveolar bone and its mucoperiosteum respond differently to stress/strain than load‐bearing bones in other locations, possibly due to differences in the mechanism of bone loading by muscles and teeth. Occlusal hypofunction was initiated by extraction of agonist teeth; the contralateral teeth were placed in hyperfunction by the surgery. Untreated animals were also studied. 3H‐proline was injected, animals were killed 1–5 weeks later, and the thicknesses of new bone and transseptal ligament were measured. After 5 weeks of altered function, total thickness (new bone + transseptal ligament) was similar in untreated and in hypofunctional and hyperfunctional situations; however, a new ratio between transseptal ligament and new bone thicknesses was established. Occlusal force was negatively correlated with new bone and positively correlated with transseptal ligament thickness; both thicknesses were statistically correlated in each functional situation (P<0.001). Hyperfunction resulted in increased transseptal ligament thickness, but decreased new bone thickness as compared to untreated controls (P<0.001). In contrast, hypofunction resulted in an increased new bone thickness, but a decreased transseptal ligament thickness (P<0.001). Tissue responses assure appropriate support for the teeth in each functional situation.
“Intermediate zone” of mammalian spleens: Light and electron microscopic study of three primitive mammalian species (platypus, shrew, and mole) with special reference to intrasplenic arteriovenous communication
Authors: Tanaka Yasukazu 
Published: February 2005

AbstractThe intermediate zone (IZ) of nonperfused and perfused spleens in three species of primitive mammals (shrew, mole, platypus) was studied morphologically. The IZ is a tissue zone consisting of plexiform vessels, probably venous capillaries, and is located transitionally between the white and red pulp. The IZ is separated from the white pulp by the arterial net (AN), in which the white pulp arteries terminate. Development of the IZ differs between the three species examined being distinctive in the platypus and shrew. The IZ is thin in the mole spleen. A closed type of arteriovenous (A‐V) anastomosis was demonstrated in or around the IZ in the two Insectivora species examined. In the shrew spleen, peripheral arterial branches running within the IZ anastomose with the AN around the follicle. The AN anastomoses eventually with venous plexi‐form vessels of the IZ around the nonfollicular area of the white pulp to form a closed system. In the mole spleen, A‐V anastomoses were noted between white pulp arteries (follicular and AN) and veins of the red pulp, either by direct communication or through fenestrated IZ vessels compatible with the plexiform vessels of the shrew spleen. A‐V anastomosis in the IZ is probable, but not confirmed, in the platypus spleen, as analysis was limited to a nonperfused specimen. Well‐developed ellipsoids were noted around arterial terminals of the IZ in the shrew spleen. Ellipsoids were also noted around all arterial terminals of the mole spleen directed to the red pulp. Most ellipsoids of the mole spleen appeared located within the IZ. No ellipsoids were present around arterial terminals of the IZ in the platypus spleen.Closed circulation was noted in terminals of the pulp artery in spleens of all three species. All pulp arteries of the mole spleen are postellipsoid segments of white pulp (AN and follicle) arteries. No ellipsoids were found around terminals of the pulp artery (penicillar artery) in shrew and platypus spleens.The IZ is probably homologous to the perilymphatic sinusoid (vein) of the lungfish spleen and may be regarded as part of the red pulp. The IZ may be representative of primitive mammalian spleens that have closed circulation. The marginal zone (MZ) of common mammalian spllens is probably a modified IZ by differentiation (remodelling) of the intrasplenic vein. In this process, with drawal of venous vessels from the IZ occurrred, leaving a lymphoreticular zone with open circulation (MZ). The marginal sinus reported in some mammalian spleens is probably a modified AN formed durig this process. Possible morphological alterations of the spleen in vertebrate phylogeny are discussed.
Presence in chicken tibialis anterior and extensor digitorum longus muscle spindles of reactive and unreactive intrafusal fibers after incubation with monoclonal antibodies against myosin heavy chains
Authors: Maier Alfred , Zak Radovan 
Published: February 2005

AbstractCross and longitudinal sections from the encapsulated portions of chicken tibialis anterior and extensor digitorum longus muscle spindles were examined to determine whether their intrafusal fibers were a structurally homogeneous or heterogeneous population. The techniques used were the histochemical actomyosin (mATPase) reaction, and fluorescence immunohistochemistry employing two monoclonal antibodies, CA‐83 and CCM‐52, that are specific for myosin heavy chains. After incubation with antibody CCM‐52, intrafusal fibers fluoresced either strongly or weakly to moderately. Antibody CA‐83 was even more selective. In addition to identifying the strongly reactive category, it clearly separated the remaining fibers into unreactive and moderately reactive groups. As a whole, after incubation for mATPase, pH 9.6 preincubation, unreactive fibers stained darker than strongly reactive fibers. Moreover, the cross‐sectional area of the unreactive fibers was significantly larger than that of the strongly reactive fibers. In the average‐size muscle spindle with six intrafusal fibers, there were four unreactive fibers and two strongly reactive fibers. In about one‐third of the receptors examined, one moderately reactive fiber was present. Taken together, the data indicate that intrafusal fibers of chicken tibialis anterior and extensor digitorum longus muscles are not structurally homogeneous. The oberserved variations can be better explained in terms of different fiber types than of continuous gradients within one type of fiber.
Migration pathways of recirculating murine B cells and CD4+ and CD8+ T lymphocytes
Authors: Pellas Theodore C. , Weiss Leon 
Published: February 2005

AbstractMigration pathways of B cell and CD4+ and CD8+ T cell subsets of murine thoracic duct lymphocytes (TDL) were mapped. Per weight, the spleen accumulated more TDL than any other organ, regardless of lymphocyte subset. Spleen autoradiographs showed early accumulations of TDL in marginal zone and red pulp. Many TDL exited the red pulp within 1 hr via splenic veins. The remaining TDL entered the white pulp, not directly from the adjacent marginal zone but via distal periarterial lymphatic sheaths (dPALS). From dPALS, T cells migrated proximally along the central artery into proximal sheaths (pPALS) and exited the white pulp via deep lymphatic vessels. B cells left dPALS to enter lymphatic nodules (NOD), then also exited via deep lymphatics.T cells homed to lymph nodes more efficiently than B cells. Lymphocytes entered nodes via high‐endothelial venules (HEV). CD4+ TDL reached higher absolute concentrations in diffuse cortex than did CD8+ T cells. However, CD8+ TDL moved more quickly through diffuse cortex than did CD4+ TDL. B cells migrated from HEV into NOD. Both T and B TDL exited via cortical and medullary sinuses and efferent lymphatics. A migration pathway across medullary cords is described.All TDL subsets homed equally well to Peyer's patches. T TDL migrated from HEV into paranodular zones while B cells moved from HEV into NOD. All TDL exited via lymphatics. Few TDL entered zones beneath dome epithelium. All subsets were observed within indentations in presumptive M cells of the dome epithelium.