Loss of hamster Leydig cells during regression after exposure to a short photoperiod

2018 ◽  
Vol 30 (8) ◽  
pp. 1137 ◽  
Author(s):  
E. Beltrán-Frutos ◽  
V. Seco-Rovira ◽  
J. Martínez-Hernández ◽  
C. Ferrer ◽  
L. M. Pastor
Keyword(s):  
B Cells ◽  
Leydig Cells ◽  
Light And Electron Microscopy ◽  
Type A ◽  
Nuclear Antigen ◽  
Control Group ◽  
C Cells ◽  
Type B ◽  
A Cells ◽  
Type C

The aim of the present study was to evaluate the changes that occur in hamster Leydig cells during regression. Animals were divided into control, mild regression (MR), strong regression (SR) and total regression (TR) groups. Leydig cells were characterised by light and electron microscopy. Terminal deoxyribonucleotidyl transferase-mediated dUTP–digoxigenin nick end-labelling (TUNEL) and proliferating cell nuclear antigen (PCNA) antibodies were used to detect apoptosis and proliferation respectively. Three types of Leydig cells (A, B and C) could be differentiated. Type A cells were small in size compared with Leydig cells from animals exposed to a long photoperiod, which was a result of a decreased cytoplasm and nucleus. Type B cells were even smaller than Type A cells in regression groups. Type C exhibited cytoplasm vacuolisation. The percentage of Type C cells from the control group was much lower than in the MR, SR and TR groups. (P < 0.05). In the SR and TR groups, there was a significant decrease in the percentage of Type B cells compared with the control and MR groups (P < 0.05). The total number of Leydig cells decreased during testicular regression (P < 0.05). The total number of Type A and B cells was significantly lower in the MR, SR and TR groups compared with the control group (P < 0.05). There were no significant differences in the proliferation and apoptosis index in the groups studied. The findings of the present study indicate that there are three types of Leydig cells (A, B and C) in all hamsters studied and that regression causes an increase in the number of Type C cells, so that the reduction in the number Leydig cells during the phases of regression studied must be the result of necrosis and/or necroptosis.

Physiological properties of rat ventral pallidal neurons recorded intracellularly in vivo

1996 ◽  
Vol 75 (4) ◽  
pp. 1432-1443 ◽  
Author(s):  
A. Lavin ◽  
A. A. Grace
Keyword(s):  
B Cells ◽  
Nucleus Accumbens ◽  
Action Potential ◽  
Type A ◽  
C Cells ◽  
Postsynaptic Potentials ◽  
A Cells ◽  
Type C ◽  
Stimulation Of

1. The physiology of ventral pallidal (VP) cells was investigated using in vivo intracellular recording and staining techniques in adult rats. Based on electrophysiological criteria, three different types of cells were found: type A cells, which fired phasic spikes that did not exhibit a substantial afterhyperpolarization (AHP), type B cells, which exhibited a slow ramplike depolarization that preceded the short-duration action potential; the spike was followed by a prominent AHP, and type C cells, which were the only cells that fired spikes in couplets or bursts, with the spikes in a burst exhibiting a progressive increase in duration and a decrease in amplitude. These cells also exhibited a rebound low threshold spikelike event. Furthermore, 18% of the VP cells recorded exhibited a slow subthreshold oscillation of the membrane potential (< 1 Hz). 2. The response of VP cells to stimulation of fibers arising from the prefrontal cortex, nucleus accumbens, and mediodorsal thalamic nucleus (MD) was examined. In contrast to our initial predictions, all cells responded to nucleus accumbens stimulation with excitation. Type A and B cells responded to nucleus accumbens stimulation with excitation and to MD stimulation with antidromic-like responses, orthodromic excitation, or evoked inhibitory postsynaptic potentials. Only type A cells responded to prefrontal cortical stimulation. Type C cells only responded to stimulation of the nucleus accumbens, which resulted in evoked excitatory postsynaptic potentials. 3. The cells in the VP therefore can be segregated into three physiologically defined groups according to action potential discharge patterns and their response to afferent fiber stimulation.

Morphology of the “Sulphur Granules” (Drusen) in Some Actinomycotic Infections. A Light and Electron Microscopic Study

1978 ◽  
Vol 15 (4) ◽  
pp. 506-518 ◽  
Author(s):  
G. Bestetti
Keyword(s):  
Cell Wall ◽  
B Cells ◽  
Amorphous Material ◽  
Light And Electron Microscopy ◽  
Type A ◽  
Cross Wall ◽  
Type B ◽  
Electron Microscopic ◽  
A Cells ◽  
Cellular Wall

The granules (Drusen) within the inflammatory lesions in three cases of infection by Actinomyeetales were studied with light and electron microscopy. The material consisted of subcutaneous granulomas caused by Actinomyces bovis in a cow, epidural granulomas caused by A. viscosus in the spinal canal of a cat and cerebral granulomas caused by Nocardia in a dog. The granules of A. bovis were 2000 to 3000 micrometers in diameter. Their centers consisted of a slightly basophilic, gram- and grocott-negative material with branching, gram-and grocott-positive filaments. The periphery was slightly basophilic or eosinophilic, but gram- and grocott-positive. Its surface was made of clubs (15 × 3.5 micrometers); they were acidophilic, gram- and grocott-negative. In the center of the granule there are numerous type a cells (coccobacillary cells with a trilaminar cell wall of 12 nanometers) and rarely type b cells (filaments with bilaminar cell wall of 30 nanometers). The periphery was made of germinative centers of type a cells. The clubs were lytic type b cells, embedded in an amorphous material. The granules (Drusen) of A. viscosus were 200 to 600 micrometers in diameter. Their center was slightly eosinophilic, gram- and grocott-negative and contained gram- and grocott-positive filaments. Their periphery was basophilic and contained alternating gram-and grocott-negative areas and radial gram- and grocott-positive filaments. There were no clubs. In the center there were type b cells (filaments with a trilaminar cellular wall of 30 nanometers). The periphery was made of germinative centers of type a cells (coccobacillary with a trilaminar cell wall of 10 to 11 nanometers). The germinative centers were separated from each other by radial bundles of type b cells. The granules (Drusen) of Nocardia were acidophilic, gram- and grocott-positive and surrounded by 1.8 × 0.5-micrometer clubs that were acidophilic, gram- and grocott-negative. There were type a cells (filamentous to bacillary with monolaminar cell wall of 19 nanometers and cross wall) and type b cells (filamentous to bacillary with monolaminar cell wall of 65 nanometers and without cross wall). The remarkable morphological differences of the three species of Actinomycetales are specific, independent from host and type of tissue, and therefore reliable for diagnostic purposes.

Comparative transduction mechanisms of hair cells in the bullfrog utriculus. I. Responses to intracellular current

1994 ◽  
Vol 71 (2) ◽  
pp. 666-684 ◽  
Author(s):  
R. A. Baird
Keyword(s):  
B Cells ◽  
Hair Cell ◽  
Hair Cells ◽  
Hair Bundle ◽  
C Cells ◽  
Type B ◽  
Lateral Border ◽  
Utricular Macula ◽  
Type C ◽  
Current Steps

1. Hair cells in whole-mount in vitro preparations of the utricular macula of the bullfrog (Rana catesbeiana) were selected according to their macular location and hair bundle morphology. The voltage responses of selected hair cells to intracellular current steps and sinusoids in the frequency range of 0.5-200 Hz were studied with conventional intracellular recordings. 2. The utricular macula is divided into medial and lateral parts by the striola, a 75- to 100-microns zone that runs for nearly the entire length of the sensory macula near its lateral border. The striola is distinguished from flanking extrastriolar regions by the elevated height of its apical surface and the wider spacing of its hair cells. A line dividing hair cells of opposing polarities, located near the lateral border of the striola, separates it into medial and lateral parts. On average, the striola consists of five to seven medial and two to three lateral rows of hair cells. 3. Utricular hair cells were classified into four types on the basis of hair bundle morphology. Type B cells, the predominant hair cell type in the utricular macula, are small cells with short sterocilia and kinocilia 2-6 times as long as their longest stereocilia. These hair cells were found throughout the extrastriola and, more rarely, in the striolar region. Three other hair cell types were restricted to the striolar region. Type C cells, found primarily in the outer striolar rows, resemble enlarged versions of Type B hair cells. Type F cells have kinocilia approximately equal in length to their longest stereocilia and are restricted to the middle striolar rows. Type E cells, found only in the innermost striolar rows, have short kinocilia with prominent kinociliary bulbs. 4. The resting potential of 99 hair cells was -58.0 +/- 7.6 (SD) mV and did not vary significantly for hair cells in differing macular locations or with differing hair bundle morphology. The RN of hair cells, measured from the voltage response to current steps, varied from 200 to > 2,000 M omega and was not well correlated with cell size. On average, Type B cells had the highest RN, followed by Type F, Type E, and Type C cells. When normalized to their surface area, the membrane resistance of hair cells ranged from < 1,000 to > 10,000 k omega.cm2. The input capacitance of hair cells ranged from < 3 to > 15 pA, corresponding on average to a membrane capacitance of 0.8 +/- 0.2 pA/cm2.(ABSTRACT TRUNCATED AT 400 WORDS)

Synaptic organization of two types of amacrine cells with CRF-like immunoreactivity in the turtle retina

1991 ◽  
Vol 6 (3) ◽  
pp. 257-269 ◽  
Author(s):  
Douglas E. Williamson ◽  
William D. Eldred
Keyword(s):  
B Cells ◽  
Plexiform Layer ◽  
Amacrine Cells ◽  
Type A ◽  
Inner Plexiform Layer ◽  
Synaptic Organization ◽  
Type B ◽  
Synaptic Contacts ◽  
A Cells ◽  
Visual Streak

AbstractThe ultrastructural features and synaptic contacts of two amacrine cell types with corticotropin-releasing factor-like immunoreactivity in the turtle retina were examined using electron immunocytochemistry. Type A cells were found only in the visual streak and had elongated dendritic arborizations that ran parallel to the visual streak. These cells arborized primarily in stratum 1 and near the border of strata 2 and 3 of the inner plexiform layer, with some processes extending into stratum 5. Type B cells were found only ventral to the visual streak and arborized primarily in a wide band in strata 4 and 5, with sparse dendritic arborizations in stratum 1.There was a diffuse cytoplasmic reaction product within each cell type; however, large labeled vesicles were rarely observed. Type A amacrine cells received many conventional synaptic contacts from amacrine cells in stratum 1 and at the border of strata 2 and 3, but only a small number of contacts in stratum 5. Bipolar synaptic contacts onto type A amacrine cells were observed in strata 1 and at the border of strata 2 and 3. The only positively identified synaptic outputs of type A cells were conventional synapses onto amacrine cells in strata 1 and at the border of 2 and 3. Type B amacrine cells received synaptic contacts from amacrine cells in strata 1 and 5, and bipolar cell synaptic input in stratum 5. They made conventional synapses onto amacrine cells in strata 1 and 5, and onto bipolar cells in stratum 5. We also found conventional synaptic contacts between unlabeled amacrine cells and type B amacrine cells outside of the primary layers of stratification. In addition, there were specialized junctions observed between type A cell profiles in stratum 1 and between type B cell profiles in stratum 5. The unique regional distributions of the type A and B cells, as well as their differences in synaptic connectivity, suggested that these amacrine cells play distinct physiological roles although they contain the same neuropeptide.

scholarly journals Image-Based Identification and Genomic Analysis of Single Circulating Tumor Cells in High Grade Serous Ovarian Cancer Patients

Cancers ◽  
2021 ◽  
Vol 13 (15) ◽  
pp. 3748
Author(s):  
Carolin Salmon ◽  
Janina Levermann ◽  
Rui P. L. Neves ◽  
Sven-Thorsten Liffers ◽  
Jan Dominik Kuhlmann ◽  
...  
Keyword(s):  
Ovarian Cancer ◽  
Tumor Cells ◽  
Circulating Tumor Cells ◽  
Genomic Analysis ◽  
Type A ◽  
Tumor Evolution ◽  
High Grade ◽  
C Cells ◽  
Type B ◽  
A Cells

In Ovarian Cancer (OC), the analysis of single circulating tumor cells (sCTCs) might help to investigate genetic tumor evolution during the course of treatment. Since common CTC identification features failed to reliably detect CTCs in OC, we here present a workflow for their detection and genomic analysis. Blood of 13 high-grade serous primary OC patients was analyzed, using negative immunomagnetic enrichment, followed by immunofluorescence staining and imaging for Hoechst, ERCC1, CD45, CD11b and cytokeratin (CK) and sCTC sorting with the DEPArrayTM NxT. The whole genome of single cells was amplified and profiled for copy number variation (CNV). We detected: Type A-cells, epithelial (Hoechstpos, ERCC1pos, CD45neg, CD11bpos, CKpos); Type B-cells, potentially epithelial (Hoechstpos, ERCC1pos, CD45neg, CD11bpos, CKneg) and Type C-cells, potentially mesenchymal (Hoechstpos, ERCC1pos, CD45neg, CD11bneg, CKneg). In total, we identified five (38.5%) patients harboring sCTCs with an altered CN profile, which were mainly Type A-cells (80%). In addition to inter-and intra-patient genomic heterogeneity, high numbers of Type B- and C-cells were identified in every patient with their aberrant character only confirmed in 6.25% and 4.76% of cases. Further identification markers and studies in the course of treatment are under way to expand sCTC analysis for the identification of tumor evolution in OC.

scholarly journals Ultrastructural localization of carbonic anhydrase II in subpopulations of intercalated cells of the rat kidney.

1990 ◽  
Vol 1 (3) ◽  
pp. 245-256 ◽  
Author(s):  
J Kim ◽  
C C Tisher ◽  
P J Linser ◽  
K M Madsen
Keyword(s):  
Electron Microscopy ◽  
B Cells ◽  
Carbonic Anhydrase ◽  
Collecting Duct ◽  
Rat Kidney ◽  
Light And Electron Microscopy ◽  
Type A ◽  
Carbonic Anhydrase Ii ◽  
Intercalated Cells ◽  
Type B

At least two configurations of intercalated cells, type A and type B, are present in the cortical collecting duct. Intercalated cells are rich in carbonic anhydrase. However, it is not known whether there are differences in the level and subcellular distribution of this enzyme between type A and type B intercalated cells. The purpose of this study was to determine the relative content and intracellular distribution of carbonic anhydrase II in the various subpopulations of intercalated cells in the rat collecting duct. A rabbit polyclonal antibody directed against mouse erythrocyte carbonic anhydrase II was employed to localize carbonic anhydrase, II by light and electron microscopy by an indirect immunoperoxidase method. A Western immunoblot analysis of homogenates of rat kidney cortex and medulla with the carbonic anhydrase II antibody revealed a single polypeptide band at 29 kDa corresponding to the molecular size of carbonic anhydrase II. By both light and electron microscopy, carbonic anhydrase II immunoreactivity was present in all intercalated cells but the intensity of staining was much greater in type A than in type B cells. In addition, immunostaining in type A cells was especially pronounced in the apical cytoplasm and apical microprojections whereas in type B cells, immunostaining was more diffuse throughout the cytoplasm. A third configuration of intercalated cell with diffuse immunostaining for carbonic anhydrase II was occasionally observed in the connecting segment. Very weak immunostaining was present in principal cells, whereas connecting tubule cells and inner medullary collecting duct cells were negative for carbonic anhydrase II.(ABSTRACT TRUNCATED AT 250 WORDS)

Separation of two bone cell populations from fetal rat calvaria and a study of their responses to parathyroid hormone and calcitonin

1983 ◽  
Vol 99 (3) ◽  
pp. 387-399 ◽  
Author(s):  
I. P. Braidman ◽  
D. C. Anderson ◽  
C. J. P. Jones ◽  
J. B. Weiss
Keyword(s):  
Alkaline Phosphatase ◽  
Parathyroid Hormone ◽  
Acid Phosphatase ◽  
B Cells ◽  
Adenylate Cyclase ◽  
Culture Medium ◽  
Cell Populations ◽  
C Cells ◽  
Type B ◽  
Type C

Bone cells released from perinatal rat calvaria by digestion with clostridial peptidase were separated into two distinct populations (designated types B and C) by equilibrium density centrifugation on a two-step gradient of Percoll. They were extensively characterized by light and electron microscopy and for behaviour in culture, acid and alkaline phosphatase activity, collagen synthesis, collagenase secretion and adenylate cyclase response to parathyroid hormone (PTH) and calcitonin. Type C cells were predominantly large with up to seven nuclei and an unusual cytoplasmic appearance in cytocentrifuge preparations. They did not proliferate in culture and we have established culture conditions which prevented their overgrowth by contaminating proliferative cells. In culture these cells had low alkaline and high acid phosphatase and high aryl sulphatase activity, and synthesized little collagen. In contrast type B cells were mostly smaller and many had irregular cytoplasmic projections. In culture they became polygonal in shape, proliferated rapidly, and reached confluence in 4–5 days. These were low in aryl sulphatase and acid phosphatase, high in alkaline phosphatase activity, and synthesized labelled collagen actively with [3H]proline and ascorbic acid included in the culture medium. The two cell populations were found to differ in culture in two important further respects. First, the type C cells showed an adenylate cyclase response to calcitonin but not to PTH, while the converse was true for type B cells; this was so over at least a 20-fold range of isobutylmethyl xanthine concentration. Secondly, type C cells in culture secreted an active collagenolytic enzyme. Type B cells secreted much lower levels of a predominantly latent collagenase which required activation by mersalyl. Co-culture of type C and type B cells led to a marked reduction in the content of active collagenase in the culture medium.

Phrenic motoneurons in the cat: subpopulations and nature of respiratory drive potentials

1979 ◽  
Vol 42 (1) ◽  
pp. 76-90 ◽  
Author(s):  
A. J. Berger
Keyword(s):  
Membrane Potential ◽  
B Cells ◽  
Input Resistance ◽  
Type A ◽  
Current Injection ◽  
Type B ◽  
Expiratory Phase ◽  
Axonal Conduction ◽  
Phrenic Motoneurons ◽  
A Cells

1. Intracellular recordings were made from 78 phrenic motoneurons (PM) in anesthetized, paralyzed, artificially ventilated cats that were slightly hypercapnic. 2. Three subpopulations of PM (types A, B, and A/B) were identified on the basis of their membrane potential trajectories during expiration (E). Type A cells exhibited wholly linear trajectories. These were rapidly hyperpolarized at the onset of E followed by a slow ramp of increasing hyperpolarization observed in 51 of 59 type A cells. Types B (13 cells) and A/B (6 cells) had nonlinear trajectories in E. Type B cells approached their end-expiratory potential levels more slowly. 3. Measurements of axonal conduction velocity, expiratory phase input resistance, initial depolarization rate, and initial spike onset during inspiration revealed that type B cells had significantly slower axonal conduction velocities, higher input resistances, greater initial depolarization rates, and earlier initial spike onsets than type A cells. The properties of type A/B were intermediate between the other cell types. These results support the hypothesis that the PM pool is not homogeneous. 4. Active E-phase inhibition of all types of PM was directly demonstrated by reversal of the increasing hyperpolarizing wave to a depolarizing wave with hyperpolarizing current injection using a bridge circuit. Thus hyperpolarization of PM during E is not merely due to a central disfacilitation. 5. During hyperpolarizing current injection the inspiratory phase membrane potential trajectory of all PM became a ramp depolarization similar to that seen during control conditions in type A cells. These results support the conclusion that all cells within the PM pool are receiving a similar central excitatory synaptic input during inspiration. The rapid initial depolarization of type B and their concomitant early spike onset is a consequence in part of a rebound excitation from their expiratory phase inhibition as well as a higher input resistance, probably due to a smaller cell size. 6. Expiratory related neural activity was recorded within the phrenic motor nucleus. It is suggested that these expiratory related neural elements, based on the temporal pattern of their activity, may be responsible for the active inhibition of PM.

scholarly journals Ionic mechanisms of two types of on-center bipolar cells in the carp retina. II. The responses to annular illumination.

1981 ◽  
Vol 78 (5) ◽  
pp. 569-589 ◽  
Author(s):  
T Saito ◽  
H Kondo ◽  
J Toyoda
Keyword(s):  
B Cells ◽  
Spectral Response ◽  
Type A ◽  
Membrane Potentials ◽  
Bipolar Cells ◽  
Membrane Properties ◽  
C Cells ◽  
Type B ◽  
Ionic Mechanisms ◽  
D Cells

On-center bipolar cells in the dark-adapted carp retina were divided into four types (A, B, C, and D) on the basis of response wave forms, spectral response properties, and electrical membrane properties. Type A and B cells responded to a spot of light with a transient depolarization followed by a plateau, whereas the response of type C and D cells were approximately rectangular in shape. The center and surround responses of type A cells had maximum spectral response of approximately 525 nm in the lower mesopic range; the polarity of both responses was reversed at positive membrane potentials as the membrane was depolarized by extrinsic current. The center and surround responses of type D cells had a maximum spectral response of approximately 625 nm in the mesopic or photopic range; the polarity of both responses was reversed at membrane potentials that were more negative than those at the dark level. The results suggest that the center and surround responses mediated by rods are generated by changes in sodium conductance, but in opposite ways; whereas those mediated by red cones are generated by changes in potassium and/or chloride conductances. In type B and C cells, which probably receive inputs from both rods and/or green cones as well as red cones, the center responses were composed of the two ionic mechanisms described above. The surround responses of many type B and C cells were dominated by only one ionic mechanism with a negative reversal potential, but in some type B cells the surround responses were resulted from two ionic mechanisms similar to those of the center responses.

Immunocytochemical response of type A and type B intercalated cells to increased sodium chloride delivery

1992 ◽  
Vol 262 (2) ◽  
pp. F288-F302 ◽  
Author(s):  
J. Kim ◽  
W. J. Welch ◽  
J. K. Cannon ◽  
C. C. Tisher ◽  
K. M. Madsen
Keyword(s):  
Sodium Chloride ◽  
B Cells ◽  
Type A ◽  
Band 3 ◽  
Intercalated Cells ◽  
Band 3 Protein ◽  
Type B ◽  
Membrane Area ◽  
A Cells ◽  
Chronic Infusion

Two populations of intercalated cells, type A and type B, are present in the rat cortical collecting duct (CCD). Type A cells are involved in proton secretion and contain an apical H(+)-adenosinetriphosphatase (ATPase) and a basolateral Cl(-)-HCO3- exchanger. Type B cells are believed to be involved in HCO3- secretion, which is mediated by a Cl(-)-HCO3- exchange process and is Cl- dependent. The aim of this study was to examine the morphological and immunocytochemical response of type B intercalated cells in the rat to increased delivery of Cl- to the CCD. This was accomplished by chronic infusion of a loop diuretic, bumetanide (30 mg.kg body wt-1.day-1), via an osmotic minipump, and simultaneous administration of 0.9% sodium chloride in the drinking water for 6 days. The kidneys were preserved by in vivo perfusion with a periodate-lysine-paraformaldehyde fixative and processed for horseradish peroxidase and protein A gold immunocytochemistry, using rabbit polyclonal antibodies against carbonic anhydrase II, proton ATPase, and band 3 protein. Chronic infusion of bumetanide in combination with a high salt intake was associated with significant changes in the intercalated cells. Type B cells were increased in size and exhibited numerous apical microvilli, increased basolateral membrane area, and marked cytoplasmic and basolateral labeling for H(+)-ATPase. In contrast, type A cells were small and had sparse apical microprojections. H(+)-ATPase immunolabeling was observed primarily over apical tubulovesicles, and there was decreased basolateral immunolabeling for band 3 protein and occasional labeling for band 3 in lysosome-like structures. These observations support the hypothesis that increased delivery of Cl- to the CCD is associated with stimulation of type B intercalated cells to secrete HCO3-. The observations in type A cells are consistent with the cells being in a resting or inactivated state.

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