The gonadotropes, LH and FSH cells, were immunohistochemically identified in the pituitary pars distalis of adult male viscacha (Lagostomus maximus maximus) using specific antibodies against hLH' hFSH' with streptavidinbiotin- peroxidase complex. distribution, size percentage immunopositive area these cells analyzed by image analysis viscachas captured during annual reproductive cycle after chronic administration melatonin. LH' FSHb showed seasonal changes area. LHb found widely distributed...

Folliculostellate cells (FSC) have been reported in pituitary of several mammalian species. FSC morphology and secreted sub- stances instrumental to the under- standing their function. The purpose this work was perform an immunohistochemi- cal, morphometric ultrastructural study pars distalis adult male viscacha analyze relation with hormone secreting cells. Immunohistoche- mistry image analysis were carried out different sectors gland, from middle (sector 1) glandular periphery 5)....

The anatomy, histology and androgen receptor immunohistochemistry of the prostate (P), seminal vesicles (SV), bulbourethral coagulant gland (CG) were studied in male viscacha, a seasonally reproductive wild rodent. Two histologically well-defined zones, peripheral central, identified prostate, according to their relationship with urethra. epithelial cells periodic acid-Schiff (PAS)-positive central zone alcian blue negative two zones. SV are paired gland, tubular, tortuous aspect formed by...

Yersinia enterocolitica evades the immune response by injecting outer proteins (Yops) into cytosol of host cells. YopH is a tyrosine phosphatase critical for virulence. However, mucosal mechanisms subverted during in vivo orogastric infection with Y. remain elusive. The results this study revealed neutrophil recruitment to Peyer's patches (PP) after YopH-deficient mutant strain (Y. ΔyopH). While wild-type (WT) PP induced major chemoattractant CXCL1 mRNA and protein levels, ΔyopH exhibited...

Abstract Lactotrophs in pituitary pars distalis (PD) of viscacha were studied by immunohistochemistry and morphometric analysis the following groups: 1) adult males throughout reproductive cycle (reproductive, gonadal regression, recovery periods), 2) melatonin‐treated adults, 3) castrated 4) prepubertal, 5) non‐pregnant females, 6) pregnant females (early, mid, late pregnancy). Immunopositive percentage area (%IA), cell PD (% PDC), number cells per reference (no.cell/RA), major cellular...

Endometriosis is characterized by the growth of endometrial-like tissue outside uterus, and it associated with alterations in expression hormone receptors inflammation. Estetrol (E4) a weak estrogen that recently has been approved for contraception. We evaluated effect E4 on endometriotic-like lesions TNF-α, (ERs), progesterone (PRs) an vivo murine model. was induced surgically female C57BL/6 mice. delivered via Alzet pump (3 mg/kg/day) from 15th postoperative day 4 weeks. significantly...

Abstract Objectives Melatonin and androgens are involved in the regulation of cell proliferation. However, effects these hormones on pituitary pars distalis ( PD ) male viscachas is not fully understood. In present study, we analysed melatonin gonadal androgens’ proliferating nuclear antigen PCNA expression. Materials methods Pituitary glands from foetuses, immature individuals, prepubertal individuals adult during their reproductive cycle, after administration castration, were used. ‐ir...

Somatotrophs were identified and quantified in pituitary pars distalis of male viscachas <i>(Lagostomus maximus maximus)</i> during the annual reproductive cycle, after administration melatonin, castration different growth stages by immunohistochemistry morphometric analysis. In adult viscachas, somatotrophs distributed throughout cycle. They oval, pyramidal or round shape with a large nucleus. The percentage immunopositive area, major cellular diameter number cells decreased...

Abstract The physiology and behavior of viscacha vary along the year according to modifications environmental signals such as photoperiod length, temperature, rainfall pattern, food composition, social interactions. pituitary pars distalis thyrotrophs (TSH cells) male were immunohistochemically identified, morphometric parameters: percentage immunopositive area (% IA), cell in PDC), number cells per reference (no. cells/RA), major cellular nuclear diameters analyzed. Three different groups...

The role of tumor necrosis factor-α (TNF-α) in shaping the microenvironment is ambiguous. Consistent with its uncertain melanoma, TNF-α plays a dual role, either acting as cytotoxic cytokine or favoring tumorigenic inflammatory microenvironment. signals via two cognate receptors, namely TNFR1 (p55) and TNFR2 (p75), which mediate divergent biological activities. Here, we analyzed impact deficiency progression B16.F1 melanoma model. Tumors developed mice lacking (TNFR1 knock-out; KO) were...

The aim of this work was to study the androgen receptors (AR) expression in pituitary pars distalis (PD) male viscachas relation growth and reproductive cycle. AR were detected by immunocytochemistry quantified image analysis. Pituitary glands from fetus, immature, prepubertal, adult during their cycle used. In fetal PD, immunoreactivity (ir) mainly cytoplasmic. immature prepubertal animals, AR-ir cytoplasmic (ARc-ir) nuclear (ARn-ir) medial region. ARn-ir cells numerous at caudal end....

Summary New evidence provides valuable information about the participation of sustentacular cells in chromaffin cell catecholamine secretion. In this process, calcium ions play an important role. It has been shown that there is intense ionic traffic between both types cells. Moreover, take active part metabolism, regulating levels ion and indirectly, synthesis release catecholamines. This background encouraged us to study population Lagostomus adrenal medulla its morphologic relationship...

The pineal gland of viscacha exhibits histophysiological variations throughout the year, with periods maximal activity in winter and minimal summer. aim this work is to analyze interstitial cells (IC) male viscachas relation season age. S-100 protein, glio-fibrillary acidic protein (GFAP), vimentin were detected adult immature animals by immunohistochemistry (IHC). Double-IHC was also performed. localized within both, IC nucleus cytoplasm. GFAP present only Vimentin expressed some IC,...

The presence of pigment has been demonstrated in different nervous structures such as those retina, substantia nigra , and locus coeruleus . These pigments have also described the pineal gland mammal species. Histochemical ultrastructural studies female viscacha ( Lagostomus maximus ) were performed to analyze pigmented cells under natural conditions evaluate a probable relation between content glandular activity during pregnancy. following techniques applied: hematoxylin-eosin,...

Animals living in nontropical climates modify their physiology and behavior to adapt seasonal environmental changes. Part of this adaptation involves the release catecholamine from sympathetic nerve endings adrenal medulla, which play a major role regulating energy balance. The aim work was investigate whether adult male viscachas natural habitat exhibits structural changes medulla during annual cycle. In August-September, chromaffin granules revealed ultrastructural suggestive piecemeal...

The aims of the present study were to determine whether castration results in quantitative immunohistochemical changes androgen receptors (AR), LH-immunoreactive (IR) cells and FSH-IR cells, analyse colocalisation AR gonadotropins pituitary pars distalis (PD) viscachas. Pituitaries processed for light electron microscopy. AR-IR, LH-IR detected by immunohistochemistry. In morphometric studies, percentage LH-IR, FSH-IR, LH-IR/AR-IR FSH-IR/AR-IR was determined. intact viscachas, distributed...

The pineal gland of mammals undergoes morphological and biochemical changes throughout the gestation period. In viscachas, a seasonal breeding rodent, pregnancy lasts approximately 154 days 3 stages can be defined, i.e., early, mid, late pregnancy. purpose this study is to analyze morphometric variations in expression S-100 protein, glial fibrillary acidic protein (GFAP), vimentin interstitial cells (IC) pregnant nonpregnant viscachas by immunohistochemistry (IHC). We also aim evaluate...