Testicular serotonin is related to mast cells but not to Leydig cells in the rat

1995 ◽  
Vol 146 (1) ◽  
pp. 15-21 ◽  
Author(s):  
R Aguilar ◽  
F Antón ◽  
C Bellido ◽  
E Aguilar ◽  
F Gaytan

Abstract Testicular serotonin (5HT) concentrations were determined by HPLC in the testes of rats treated neonatally with oestradiol benzoate (EB) and in adult rats treated with the Leydig cell cytotoxic ethylene dimethane sulphonate (EDS). 5HT concentrations were related to mast cell numbers. EB-treated rats showed an accumulation of mast cells in the testes at 35 and 70 days of age and increased 5HT concentrations in both the interstitial fluid and the testicular capsule, whereas no increases in 5HT concentrations or in the number of mast cells were found for the ventral prostate of these animals. On the contrary, 5HT concentrations were not related to the number of Leydig cells. In EB-treated rats, in which Leydig cells were nearly absent at 35 days of age, 5HT concentrations were significantly increased. Furthermore, EDS-treated rats did not show significant changes in 5HT concentrations, in spite of the elimination of Leydig cells. These data suggest that mast cells are a major source of serotonin in the rat testis. Journal of Endocrinology (1995) 146, 15–21

1996 ◽  
Vol 150 (1) ◽  
pp. 57-65 ◽  
Author(s):  
F Gaytan ◽  
C Bellido ◽  
C Morales ◽  
M García ◽  
N van Rooijen ◽  
...  

Abstract Testicular macrophages are a relevant cell type for the regulation of Leydig cell steroidogenesis. The availability of liposome technology allows in vivo manipulation of macrophages in order to analyze their role in the regulation of the hypothalamic-pituitary-testicular axis. In this study, adult (70 days of age) and prepubertal (22 days of age) rats were injected intratesticularly with liposomes containing either dichloromethylene diphosphonate (C12MDP) to deplete testicular macrophages or muramyl tripeptide (MTP-PE) to activate them. Control rats were injected with the corresponding volumes of 0·9% NaCl. Animals were killed 10 days after treatment. Adult rats injected bilaterally or unilaterally with C12MDP liposomes showed increased serum LH and testosterone concentrations, as well as increased testosterone concentrations in the testicular interstitial fluid. In unilaterally injected rats, testosterone concentrations in the interstitial fluid were higher in the macrophage-containing testes than in the contralateral, macrophage-depleted testes. Adult rats treated bilaterally with MTP-PE liposomes showed increased numbers of testicular macrophages, whereas the number of Leydig cells was unchanged. Serum LH concentrations were decreased, but no changes were found in testosterone concentrations. Prepubertal rats treated bilaterally with C12MDP liposomes showed decreased numbers of Leydig cells. However, serum LH and testosterone concentrations were increased. Otherwise, prepubertal rats treated bilaterally with MTP-PE liposomes showed increased numbers of macrophages and Leydig cells, as well as increased serum testosterone concentrations. These data suggest that testicular macrophage-derived factors act at two different levels in the pituitary-testicular axis: first, at a central level by inhibiting LH secretion, and secondly, at a local level by stimulating Leydig cell steroidogenesis. Journal of Endocrinology (1996) 150, 57–65


1978 ◽  
Vol 112 (1) ◽  
pp. 103-109 ◽  
Author(s):  
Lennart Enerbäck ◽  
Lennart Mellblom

1993 ◽  
Vol 11 (3) ◽  
pp. 319-324 ◽  
Author(s):  
A Moore ◽  
C-L C Chen ◽  
J R E Davis ◽  
I D Morris

ABSTRACT IGF-I mRNA has been demonstrated in testicular tissue and, more recently, localized specifically to Leydig cells. This study investigated the expression of IGF-I and side-chain cleavage enzyme (SCC) mRNA in two preparations of rat interstitial testicular cells which were separated by buoyant density into Leydig cell-enriched and -depleted fractions. RNA was prepared from interstitial cells obtained from the testes of untreated adult and immature rats and adult rats treated with human chorionic gonadotrophin (hCG) or ethane dimethanesulphonate (EDS; to destroy Leydig cells). IGF-I mRNA was detected in all samples, with five major transcripts ranging from 7·5 to 0·6 kb. Leydig cells (3β-hydroxysteroid dehydrogenase-positive and sensitive to EDS) expressed abundant IGF-I and SCC mRNAs, and levels of both were increased following hCG treatment. However, in addition, IGF-I mRNA which was derived from non-Leydig interstitial cells was detected, in the complete absence of SCC message, either in the more buoyant interstitial cells or in both interstitial cell fractions following the destruction of Leydig cells by EDS treatment. IGF-I expression in the Leydig cell-depleted cell fraction was also increased by hCG treatment, and it is therefore suggested that at least part of this non-Leydig interstitial cell IGF-I mRNA originates in Leydig cell precursors. In conclusion, Leydig cells are not the sole origin of IGF-I mRNA in the testis, and the non-Leydig cell expression may be an important component of testicular IGF-I production.


1997 ◽  
Vol 34 (1) ◽  
pp. 23-30 ◽  
Author(s):  
M. M. Welle ◽  
L. Audigé ◽  
J.-P. Belz

Endometrial biopsies of 44 broodmares were histologically examined on days 3, 6, and 9 postpartum. The mares were subdivided into three groups according to the course of the puerperal period. In 29 mares, parturition and expulsion of the placenta was normal, six mares showed dystocia, and in nine mares, the placenta was retained for >2 hours. Tissue samples were evaluated histologically, and the average numbers of granulocytes, lymphocytes, macrophages, siderophages, and mast cells was determined. Protease content of mast cells was examined with a double-enzyme immunohistochemical staining technique, using a histochemical reaction for chloroacetate esterase and fast blue to detect chymase activity and an immunohistochemical staining method with a polyclonal antibody and fast red for the detection of tryptase. Analyzing the cell numbers using the statistical software Statistica, a marked inflammatory reaction was observed in the endometrium postpartum. Although the number of granulocytes decreased during the first 9 days postpartum, the number of lymphocytes, macrophages, and siderophages increased. No significant difference in the number of any of these cell types could be demonstrated in the three different courses of the puerperal period, although the numbers of these cells seemed to be lower in mares with dystocia. In contrast with other cells, no change in the number of endometrial mast cells was observed during the puerperal period, but a significantly lower number were found in the endometrium of mares with retained placenta. The enzyme immunohistochemical double-labeling technique could demonstrate only tryptase-positive mast cells; no chymase activity was detectable in any endometrial mast cells. The number of mast cells detected with the metachromatic staining technique was significantly higher than that detected with double labeling. These results support the hypothesis that a sufficient number of mast cells may be necessary for a normal postnatal period and suggest a mast cell subtype in the equine endometrium that is tryptase and chymase negative.


1984 ◽  
Vol 102 (3) ◽  
pp. 319-327 ◽  
Author(s):  
R. M. Sharpe ◽  
I. Cooper ◽  
D. G. Doogan

ABSTRACT Adult rats were made unilaterally cryptorchid (UCD) and 6–7 weeks later Leydig cells were isolated from the scrotal and abdominal testes and their capacity to secrete testosterone in vitro was compared. Basal testosterone production by Leydig cells from the abdominal testes of UCD rats was lowered, compared with cells from the contralateral scrotal testes, whilst their responsiveness to both human chorionic gonadotrophin and an LH releasing hormone agonist was enhanced two- to threefold (P< 0·001) compared both with cells from the contralateral scrotal testes and with cells isolated from untreated rats of the same age. In the UCD rats, concentrations of testosterone in testicular interstitial fluid (IF) were reduced (P< 0·001) by 70–90% in abdominal, compared with scrotal, testes. A similar reduction was evident in the levels of testosterone in spermatic venous blood, and both this decrease and that in IF levels of testosterone varied according to the degree of testicular involution. The ontogeny of the above changes was investigated. After induction of unilateral cryptorchidism, the weight of the abdominal compared with the scrotal testis declined slowly, such that by day 5 there was only a 25% reduction in weight compared with a 70% reduction by day 40. In contrast, the levels of testosterone in IF from abdominal testes declined rapidly, such that by day 5 an 80% reduction was attained, compared with scrotal testes, with little further change by day 40. Hormone-stimulated testosterone production by Leydig cells isolated from the abdominal testes was unchanged or marginally reduced over the first 3 days compared with cells from the scrotal testes, but by day 5 there was a significant increase in responsiveness; this increase was of smaller magnitude than that evident at day 40. These results suggest a possible association between the fall in intratesticular levels of testosterone induced by unilateral cryptorchidism and the Leydig cell hypertrophy and hyper-responsiveness that occurs in the same testes. The implications with respect to altered Sertoli–Leydig cell interaction are discussed. J. Endocr. (1984) 102, 319–327


1987 ◽  
Vol 114 (3) ◽  
pp. 459-467 ◽  
Author(s):  
V. Papadopoulos ◽  
P. Kamtchouing ◽  
M. A. Drosdowsky ◽  
M. T. Hochereau de Reviers ◽  
S. Carreau

ABSTRACT Production of testosterone and oestradiol-17β by Leydig cells from adult rats was stimulated by LH or dibutyryl cyclic AMP (10 and 2·5-fold respectively). The addition of spent medium from normal, hemicastrated or γ-irradiated rat seminiferous tubule cultures, as well as from Sertoli cell cultures, to purified Leydig cells further enhanced both basal (44 and 53% for testosterone and oestradiol-17β respectively) and LH-stimulated (56 and 18%) steroid output. Simultaneously, a decrease (20–30%) in intracellular cyclic AMP levels was observed. This stimulating factor (or factors) secreted by the Sertoli cells is different from LHRH, is of proteinic nature and has a molecular weight ranging between 10 000 and 50 000; its synthesis is not controlled by FSH nor by testosterone. This factor(s) involved in rat Leydig cell steroidogenesis, at a step beyond the adenylate cyclase, does not require protein synthesis for testosterone formation whereas it does for oestradiol-17β production. It should be noted that a germ cell–Sertoli cell interaction modulates the synthesis of this factor(s). J. Endocr. (1987) 114, 459–467


2012 ◽  
Vol 7 (1) ◽  
pp. 25-32 ◽  
Author(s):  
Vesna Rajkovic ◽  
Renata Kovac ◽  
Ivana Koledin ◽  
Milica Matavulj

AbstractAtrazine is a commonly used pesticide in the US and the non-EU countries. It is classified as an endocrine-disrupting chemical and is well-known for its reproductive toxicity in mammals and lower vertebrates. The study on atrazine effects on thyroid mast cells was performed on juvenile/peripubertal and adult male Wistar rats orally gavaged with atrazine at doses of 50 mg/kg of body weight (bw) or 200 mg/kg bw. In order to visualize the mast cell population within the thyroid gland, a histochemical staining method of toluidine blue was used. The results of the histological evaluation demonstrated a prominent increase in mast cell degranulation in both age groups and at both atrazine doses. According to the stereological analysis, a statistically significant decrease in the mast cell volume density in the young rats exposed to a higher dose of atrazine was found when compared to the corresponding control. The numerical density of mast cells significantly decreased in a higher-dose atrazine treated adults in comparison to the control. The obtained data suggest that atrazine-affected mast cells would probably have a consequent influence on thyroid follicular cells and/or thyroid microvasculature via paracrine action of released mediators, but might also be involved in already suggested thyroid cancerogenesis.


Reproduction ◽  
2010 ◽  
Vol 139 (1) ◽  
pp. 177-184 ◽  
Author(s):  
P J O'Shaughnessy ◽  
A Monteiro ◽  
G Verhoeven ◽  
K De Gendt ◽  
M H Abel

FSH and androgen act to stimulate and maintain spermatogenesis. FSH acts directly on the Sertoli cells to stimulate germ cell number and acts indirectly to increase androgen production by the Leydig cells. In order to differentiate between the direct effects of FSH on spermatogenesis and those mediated indirectly through androgen action, we have crossed hypogonadal (hpg) mice, which lack gonadotrophins, with mice lacking androgen receptors (AR) either ubiquitously (ARKO) or specifically on the Sertoli cells (SCARKO). These hpg.ARKO and hpg.SCARKO mice were treated with recombinant FSH for 7 days and testicular morphology and cell numbers were assessed. In untreated hpg and hpg.SCARKO mice, germ cell development was limited and did not progress beyond the pachytene stage. In hpg.ARKO mice, testes were smaller with fewer Sertoli cells and germ cells compared to hpg mice. Treatment with FSH had no effect on Sertoli cell number but significantly increased germ cell numbers in all groups. In hpg mice, FSH increased the numbers of spermatogonia and spermatocytes, and induced round spermatid formation. In hpg.SCARKO and hpg.ARKO mice, in contrast, only spermatogonial and spermatocyte numbers were increased with no formation of spermatids. Leydig cell numbers were increased by FSH in hpg and hpg.SCARKO mice but not in hpg.ARKO mice. Results show that in rodents 1) FSH acts to stimulate spermatogenesis through an increase in spermatogonial number and subsequent entry of these cells into meiosis, 2) FSH has no direct effect on the completion of meiosis and 3) FSH effects on Leydig cell number are mediated through interstitial ARs.


2018 ◽  
Vol 48 (9) ◽  
Author(s):  
Bárbara Hess Rodrigues Gonçalves ◽  
Bruna Dantas Matos ◽  
Mariana Batista Rodrigues Faleiro ◽  
Emmanuel Arnhold ◽  
Moema Pacheco Chediak Matos ◽  
...  

ABSTRACT: In this study the correlation between the clinical score, mast cell count and interleukin 31 (IL-31) immunostaining in the skin of dogs with atopic dermatitis was determined. A total of 31 dogs of different breeds, from one to eight years of age, were chosen for the study. The 20 females and 11 males were categorized based on the CADESI-4 system, as having discrete, moderate or marked atopic dermatitis. Skin samples were collected from the axillary and interdigital regions and stained with hematoxylin and eosin for cytohistomorphological analyses and toluidine blue to evaluate the mast cell counts, and immunohistochemistry for the IL-31 immunostaining. Animals revealing higher atopic dermatitis scores had greater numbers of mast cells and IL-31 immunolabeled cells. More numbers of cells immunolabeled for IL-31 were evident in the axillary skin compared with the interdigital skin in dogs having this condition. A correlation was identified between the clinical scores and mast cell numbers in the interdigital region, as well as between the clinical scores and number of cells immunolabeled for IL-31 in the axillary area. A correlation was also reported between the mast cell numbers and IL-31 immunolabeled cells only in the axillary skin, and none in the interdigital regions. It was thus concluded that the mast cells and IL-31 are involved in the pathogenesis of the canine atopic dermatitis (CAD), as well as lymphocytes and plasma cells. It was also observed that the higher the degree of clinical severity of the disease, the more the numbers of mast cells and IL-31 in the skin of those animals suffering from CAD, which implies the influence of these immunological constituents on the genesis of pruritus and disease progression.


1987 ◽  
Vol 112 (2) ◽  
pp. 311-NP ◽  
Author(s):  
H. D. Nicholson ◽  
R. T. S. Worley ◽  
S. E. F. Guldenaar ◽  
B. T. Pickering

ABSTRACT An oxytocin-like peptide is present in the interstitial cells of the testis, and testicular concentrations of oxytocin have been shown to increase seminiferous tubule movements in vitro. We have used the drug ethan-1,2-dimethanesulphonate (EDS), which depletes the Leydig cell population of the adult rat testis, to examine further the relationships between the Leydig cell, testicular oxytocin and tubular movements. Adult rats were injected i.p. with a single dose of EDS (75 mg/kg) or of vehicle (25% dimethyl sulphoxide). Histological study 3 and 10 days after treatment with EDS showed a reduction in the number of interstitial cells, and levels of oxytocin immunoreactivity were undetectable by radioimmunoassay. Immunostaining revealed very few oxytocin-reactive cells. Spontaneous contractile activity of the seminiferous tubules in vitro was also dramatically reduced, but could be restored by the addition of oxytocin to the medium. Four weeks after EDS treatment, the interstitial cells were similar to those in the control animals both in number and in immunostaining; immunoassayable oxytocin was present and tubular movements were normal. The EDS effect, seen at 3 and 10 days, was not altered by daily treatment with testosterone. However, repopulation of the testes with oxytocin-immunoreactive cells was not seen until 6 weeks in the testosterone-treated animals. We suggest that the Leydig cells are the main source of oxytocin immunoreactivity in the testis and that this oxytocin is involved in modulating seminiferous tubule movements and the resultant sperm transport. The results also imply that testosterone does not play a major role in controlling tubular activity in the mature rat. J. Endocr. (1987) 112, 311–316


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