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1.
Studies were carried out on adult rats of Wistar strain. Six weeks after postpubertal gonadectomy some of the orchiectomized rats were injected with a single dose of testosterone cypionate and ovari-ctomized rats with estradiol cypionate (17 beta-cyclopentyloproprionate esters of testosterone or estradiol). The control rats were sham operated. Investigations were carried out 8 weeks after surgery. Absolute and relative adrenal weight is lower in the male than in the female rat. Orchiectomy increases these weights while testosterone restores them to their normal level. Ovariectomy has no effect on the weight of adrenal, estradiol, however, increases the relative weight of the gland. The adrenal cortex of the adult female is wider than in the adult male rat and in female gland sudanophobic zone is lacking. Orchiectomy leads to the broadening of the adrenal cortex and testosterone replacement has an opposite effect. Ovariectomy has no effect on the structure of adrenal cortex and estradiol replacement resulted in the narrowing of zona glomerulosa. There were no differences in the nuclear-cytoplasmic ratio of zona glomerulosa cells in male and Female rats and neither gonadectomy nor gonadal hormone replacement has no effect on this parameter. The nuclear-cytoplasmic ratio of zona fasciculata cells in the male is markedly higher than in female. Orchiectomy lowers this ratio and testosterone restores it to the normal level. Neither ovariectomy nor estradiol replacement has effect on the nuclear-cytoplasmic ratio of zona fasciculata cells. Similar changes as those in the zona fasciculata were observed in zona reticularis cells. Among the oxidoreductases studied, the most marked sex differences were found in alpha-glycerophosphate dehydrogenase activity. In control female rats an intense reaction for this enzyme is observed in broad band of cells of the zona fasciculata interna, while in male rats only individual cells showed this reaction. In orchiectomized rats the reaction for this enzyme is similar as in control female rats and testosterone restores it to normal. Ovariectomy has no effect on localisation of reaction while after estradiol replacement reaction was more intense. Regarding the remaining oxidoreductases studied, in the adrenal cortex of rats of both sexes no marked differences were observed in localization, however, intensity of reaction depended upon applied experimental conditions. More distinct sex differences were observed in topochemistry of some hydrolases and intensity of reaction depended upon the applied experimental conditions.  相似文献   

2.
Summary Adrenal glands of adult female rats are heavier than the glands of corresponding male rats. Postpubertal orchiectomy increases the adrenal weight, an effect restored by testosterone replacement. Under the same conditions ovariectomy of 8 weeks duration does not change the adrenal weight while estradiol replacement enhances the relative adrenal weight.Karyometric studies have shown that nuclei in the female zona fasciculata cells are larger (app. 18%) than those of the male. Similar but only slight differences (2%) were observed in the zona reticularis. Orchiectomy results in enlargement of cell nuclei within all zones of the adrenal cortex; testosterone replacement has the opposite effect. Ovariectomy of 8 weeks duration slightly enhances the volume of nuclei of the zona glomerulosa cells, has no effect on the nuclei of the zona fasciculata and reduces the volume of nuclei in the zona reticularis. Estradiol replacement reduces the volume of nuclei of the zona glomerulosa cells but increases nuclear volume in the zona fasciculata and in the zona reticularis.Thus testosterone has an inhibitory effect on the adrenal cortex of the rat while the physiologic effect of estradiol on the morphology of this gland, particularly on the zona fasciculata cells is rather dubious.The author wishes to thank Mrs. B. Westerska and Miss K. Siejak for excellent technical assistance.This research was supported in part by a grant from the Zoological Committee, 2nd Department, Polish Academy of Sciences.This paper is dedicated to the memory of late Kazimierz Mietkiewski, M.D., Ph.D. whose encouragements and suggestions were most stimulating for my work.  相似文献   

3.
Summary In a total of 120 rats the number of 3H-Tdr-labelled nuclei of the adrenocortex was counted during various phases of the estrous cycle. In two separate experiments cyclic variations in the number of DNA synthesizing cells were found. The labelling index of the zona glomerulosa showed a significant maximum in proestrus whereas in zona fasciculata a minimum was revealed in estrus. In the glomerulosa the maximum of labelled cells was followed by a mitotic peak in estrus. Due to very low numbers of labelled cells no rhythm was found in the reticularis. The possible endocrine regulations of this endogenous rhythm of adrenocortical cell replication are discussed.The authors wish to express their appreciation for the expert assistance in the statistical evaluation of data rendered by Dr. Trieb and for the reliable technical aid by Mr. Majer  相似文献   

4.
Gonadectomy or sham operations were performed on rats of Wistar strain weighing 150--170 g. Animals were sacrificed in groups, males 397 days and females 395 days after surgery. 14 days before autopsy some of the gonadectomized rats were injected with a single dose of depo-testosterone or depo-estradiol respectively. Absolute as well as relative adrenal weights were larger in female than in male rats. Long-term orchiectomy did not change these weights while testosterone, if compared with control, lowers the weights of the adrenals. Long-term ovariectomy lowers the weights of the glands and estradiol reversed them to the control level. Adrenal cortex of rats studied show irregular zonation. Within the zona fasciculata two types of cells were observed--with strongly eosinophilic and pale cytoplasm. In some cases groups of hypertrophied cells surrounded by spindle-shaped cells were observed. Neither long-term gonadectomy nor gonadal hormone replacement has a marked effect on the structure of the adrenal cortex. In male and female rats there was no difference in the volume of single zona fasciculata and reticularis cells. Long-term orchiectomy has no effect on this volume while testosterone resulted in a lowering of volume of zona fasiculata cells. Neither long-term ovariectomy nor estradiol has an effect on morphometric parameters studied in the fasciculata and reticularis zones. Distinct sex differences and dependence on sex hormones were found in reactions for alpha-glycerophosphate dehydrogenase and nonspecific esterases activity.  相似文献   

5.
The immunohistochemical localization of the somatostatin receptor subtype sst2A was investigated in the rat adrenal gland using SS-800 polyclonal antibody. The sst2A immunopositivity was found in all adrenocortical zones and in adrenal medulla, the reaction being slightly more intense in zona glomerulosa and medulla. The administration of the potent agonist of sst2 receptors - octreotide - resulted in the enhancement of the immunopositivity in zona glomerulosa and medulla, whereas chronic exposure of the rats to diethylstilbestrol led to enhancement of the immunopositivity in zona glomerulosa and in the external part of zona fasciculata.  相似文献   

6.
K S Szalay  G Folly 《FEBS letters》1992,296(1):87-89
The combined effects of ACTH, beta-endorphin (beta-EP) and alpha-MSH were studied on the corticosteroidogenesis of isolated rat adrenocortical zona fasciculata and zona glomerulosa cells. beta-EP potentiated the effects of ACTH and alpha-MSH on the zona fasciculata corticosterone production but inhibited those on the zona glomerulosa aldosterone production. beta-EP did not affect the combined action of 4 x 10(-11) M ACTH and 5 x 10(-9) M alpha-MSH on the zona fasciculata or the zona glomerulosa cells, but it inhibited the stimulatory action of the combination of 1.6 x 10(-10) M ACTH and 10(-9) M alpha-MSH on the zona glomerulosa aldosterone production. An interaction of ACTH, beta-EP and alpha-MSH in relation to the zona fasciculata and zona glomerulosa corticosteroid production was found.  相似文献   

7.
Summary The cytological aspects of sexual dimorphism in the rat adrenal cortex and its relationship to the gonads have been investigated. The adrenal glands of mature female rats were heavier than those of males, and morphometry showed that this was almost exclusively due to conspicuous differences in the volume of cells of the zona fasciculata (ZF) and zona reticularis (ZR). Stereology demonstrated that the volume of the mitochondrial and lipid droplet compartments, as well as the surface area per cell of mitochondrial cristae and smooth endoplasmic reticulum tubules, were markedly higher in the ZF and ZR cells of female animals. Orchiectomy increased and ovariectomy decreased the adrenal weight, by eliciting hypertrophy and atrophy, respectively, of ZF and ZR cells; these effects of gonadectomy were reversed by the appropriate gonadal hormone replacement. It is suggested that the sexual dimorphism of the rat adrenal cortex may depend upon the inhibitory action of testosterone and the stimulatory effect of estradiol on the hypothalamo-hypophyseal-adrenal axis.  相似文献   

8.
Proliferation kinetics in the zones of the adrenal cortex of female rats after castration are reported. Following ovariectomy a wave of increased cell proliferation was observed in the zona glomerulosa and zona fasciculata after 1 and 2 days respectively. Increased cell proliferation in the zona reticularis was only slight. Cell proliferation returned to the level in control animals at 4 weeks. It is assumed that the regulative process following ovariectomy takes place directly in the adrenal cortex but it is possible that steroid metabolism in the liver is of importance. No relationship between the 3H-TdR labelling index (LI) and the mitotic index (MI) was observed.  相似文献   

9.
The effects of chronic treatment (up to 9 consecutive days) with 7,12-dimethylbenzathracene (DMBA) on the adrenal glands of adult male Wistar rats were investigated. Morphometry showed that DMBA provokes atrophy of the zona reticularis which was due to the decrease in both cell volume and number. The zona fasciculata showed only a decrease in the cell volume, whereas the zona glomerulosa did not display any significant changes. Autoradiography demonstrated that DMBA induces a significant increase in the number of mitoses and "S" phase cells in the zona glomerulosa and outer zona fasciculata, which may be interpreted as a repair mechanism of the DMBA-provoked slight necrosis in the inner adrenocortical layers. The mechanism(s) underlying the cytotoxic effect of DMBA is discussed in the light of our ultrastructural observations showing that the chemical causes a decrease in the volume of the mitochondrial and nuclear compartments and in the surface of smooth endoplasmic reticulum as well as an increase in the volume of the lipid compartment.  相似文献   

10.
11.
Bhattacharyya, T. K., Butler, D. G., Price, C. S. 1980. Ultrastructural characteristics of adult rat adrenocortical cells maintained in vitro with and without ACTH. (Ramsay Wright Zoological Laboratories, Department of Zoology, University of Toronto, and Division of Endocrinology, Toronto Western Hospital, and Department of Medicine, University of Toronto, Canada.) — Acta zool. (Stockh.) 61(1): 9–21. The ultrastructural morphology of adrenocortical cells of adult rats maintained in culture for four days with and without corticotropin (ACTH) was studied in comparison to freshly dissociated cells. Identification of cells belonging to zona glomerulosa, zona fasciculata, and zona reticularis was made on the characteristics of the mitochondria and smooth endoplasmic reticulum (SER), and was confirmed by comparison with cellular layers from intact adrenals. Without ACTH, glomerulosa and fasciculata cells showed disappearance of SER, atrophied Golgi apparatus (GA), and a striking proliferation of granular reticulum. Fascicular cells had a loss in mitochondrial matrix density and the mitochondrial cristae showed a tendency to convert to lamellar glomerulosa-type cristae. Zona reticularis cells were not strikingly altered. Maintenance with ACTH led to increased cell size and islet formation of cortical cells. Glomerulosa cells had normal appearance and fasciculata cells manifested a pronounced development of GA and SER, and a normal configuration of mitochondria. The effects of ACTH on glomerulosa cells suggest a trophic influence of ACTH on these cells in vitro. The alterations observed in fascicular cell mitochondria and SER can be explained in terms of known concepts of steroid biosynthesis and basically agree with the patterns of steroid synthesis observed in these cells previously (Price et al. 1975).  相似文献   

12.
M L?w  K S Szalay  L Kisfaludy 《Peptides》1990,11(1):29-31
To investigate the role of charged chain ends in the corticosteroidogenic effect of ACTH/MSH(4-10), acetyl and amide derivatives of ACTH/MSH(4-10) were synthesized and tested in isolated zona glomerulosa and zona fasciculata cells. ACTH/MSH(4-10)-NH2, Ac-ACTH/MSH(4-10) and Ac-ACTH/MSH(4-10)-NH2 (10 microM to 1 mM) stimulated the aldosterone production of zona glomerulosa cells, whereas these peptides did not stimulate the corticosterone production of zona fasciculata cells, even at 1 mM concentration. As ACTH/MSH(4-10) has been shown to have a steroidogenic effect on both types of adrenocortical cells, both charged chain termini seem to be essential for triggering of the corticosterone production of zona fasciculata cells, but for aldosterone production their presence appears not to be important.  相似文献   

13.
Interstrain differences in the structure of the mouse and rat adrenal cortex are well known, but related data on rabbits are not available. This study was planned to demonstrate possible strain differences in rabbit adrenal morphology and morphological evidence of a communication between cortex and medulla. For this purpose, the zonation of the adrenal cortex of intact mature male and female rabbits of different strains (New Zealand, Chinchilla and California) were compared using morphometry and the corticomedullary junction was evaluated for close relationship. Marked intersex and interstrain differences were found in the adrenocortical zonation. Female rabbits had larger adrenocortical zones than corresponding males. The rabbits of Chinchilla and California strains had the largest cortical sizes. This difference depended largely upon the higher thickness of the zona fasciculata. Whereas, there were no significant strain differences in the thickness of zona glomerulosa and zona reticularis. Furthermore, examination of corticomedullary junction showed that cortex and medulla were interwoven. Single and small accumulations of cortical cells were spread throughout the medulla. Our morphological data showed the presence of significant interstrain differences in the adrenocortical zonation in the rabbits and provide evidence for a possible paracrine interaction between medullary and cortical cells.  相似文献   

14.
《Bone and mineral》1994,24(1):43-58
This study examined the effects of estrogen (17β-estradiol) and testosterone on the growth of long bones in male and female mice, with and without gonadectomy. Weight and nose-to-tail length were determined at 3 weeks of age at time of gonadectomy, 7 days later at the onset of hormone therapy, and throughout the treatment period. Gonadectomized mice exhibited an initial weight gain during the pretreatment period but length was unaffected. Hormone treatment altered weight gain in surgical and intact animals in a gender- and hormone-dependent manner. Estradiol enhanced weight gain in intact mice, but inhibited weight gain in ovariectomized mice. Lower doses of estradiol increased weight gain in orchiectomized mice at early time points. Testosterone increased weight in intact females and males, but not in gonadectomized mice. Estradiol increased nose-to-tail length in intact females at early time points, but inhibited length in ovariectomized females at later times, and it decreased length in intact males. Testosterone increased length in normal females and normal males. Serum Ca was unaffected by ovariectomy, but orchiectomy resulted in decreased levels. Estradiol reduced serum Ca in gonadectomized animals; serum Ca was increased by estradiol treatment in intact females. Changes in tibial bone weight, ash weight and mineral composition, and relative sizes of epiphyseal and metaphyseal bone were gender-, gonadectomy- and hormone-specific. Bone weight was greater in ovariectomized mice. Ash weight per bone was comparable, but there was an increase in Ca and P content with ovariectomy. Estradiol increased bone weight, ash content, and bone Ca and P in ovariectomized and intact females. Orchiectomy alone did not alter bone weight, ash content, or Ca and P, but orchiectomized mice were sensitive to estradiol; all parameters were increased in the orchiectomized animals treated with estradiol. Analysis of the ash content and Ca and P per mg bone, rather than per bone, demonstrated estradiol and testosterone alter net bone formation, but not the amount of mineral per unit bone. Ovariectomy increased hypertrophic cartilage. While estradiol did not alter tibial area in ovariectomized mice, it caused an increase in intact females. The total amount of growth plate cartilage in ovariectomized animals was decreased by estradiol to levels typical of intact animals due to a greater decrease in the hypertrophic cartilage in the ovariectomized mice, as well as a greater increase in metaphyseal bone area. Testosterone had no effect on these parameters in the females. Orchiectomy decreased the amount of growth plate cartilage, but increased the hypertrophic zone. Estradiol increased growth plate cartilage in intact male mice, but decreased it in orchiectomized mice. This difference was also seen in the hypertrophic zone. Total growth plate cartilage and hypertrophic cartilage were increased by testosterone in intact males, whereas metaphyseal and epiphyseal bone area were decreased. The results show for the first time that there is a gender-specific response in both male and female mice to both estradiol and testosterone, whether or not the animals have been gonadectomized. For many parameters, orchiectomized mice behave like females in response to both sex steroids, indicating that the male gonad is needed for mouse bone to exhibit the male phenotypic response to estradiol and testosterone.  相似文献   

15.
The steroidogenic action of ACTH/alpha-MSH fragments was studied on isolated zona glomerulosa and zona fasciculata cells dispersed by collagenase. ACTH-(4-7), ACTH-(6-10), ACTH-(4-10) and ACTH-(11-13) stimulated corticosterone production of the zona fasciculata and aldosterone production of the zona glomerulosa cells. ACTH-(7-10) was ineffective. ACTH-(4-7) appeared to be the most potent peptide of the tested fragments. None of the fragments affected the steroidogenic action of ACTH-(1-39). It is suggested that similar to the melanotropic effect of alpha-MSH two 'message' sequences for adrenocortical stimulation exist in the alpha-MSH part of the ACTH molecule.  相似文献   

16.
The role of ACTH in the synthesis of the adrenocortical hormones has been largely described. In order to investigate the localization of this peptide at the subcellular level of the adrenal glomerulosa and fasciculata cells, an immunocytological method was used. Rat adrenals were fixed and frozen. Ultrathin sections obtained by cryoultramicrotomy, were incubated with anti-beta (1-24) ACTH or anti-alpha (17-39) ACTH sera. The antigen-antibody reaction was detected by PAP complexes (revealed by 4-chloro-1-naphthol) or with protein A-colloidal gold or IgG-colloidal gold. The results obtained were the same whatever the antisera of the technique employed. All the cells of the adrenal zona glomerulosa and zona fasciculata were labelled. ACTH-like immunoreactivity in zona glomerulosa and zona fasciculata cells was observed at the plasma membrane level, in cytoplasmic matrix, mitochondria and nucleus (in the euchromatin close to the heterochromatin aggregations and, occasionally, associated with the nucleolus). No immunoreactivity was observed when non-immune serum or anti-ACTH serum preincubated with ACTH were used, nor there was any modification of the immunocytochemical reaction when anti-ACTH serum incubated with heterologous antigens was employed. These data, demonstrate the presence of endogenous ACTH in both adrenal glomerulosa and fasciculata cells, and suggest that the peptide is internalized after binding to the plasma membrane.  相似文献   

17.
α-MSH (10?9 ? 6×10?7M) potentiates the effect of ACTH (10?11 ? 5×10?9M) on adrenocortical steroidogenesis decreassng ED50 of ACTH from 220 to 183 pg/ml on zona fasciculata corticosterone-, and from 739 to 437 pg/ml on zona glomerulosa aldosterone production. α-MSH alone increases aldosterone production of zona glomerulosa cells in doses (10?9 ? 6×10?7M) that do not stimulate zona fasciculata corticosterone production. The response of zona glomerulosa aldosterone production to α-MSH can be characterized by a bi-phase dose-response curve.  相似文献   

18.
Low-density lipoprotein (LDL) receptor activity and the concentration of cholesterol were measured in the outer (glomerulosa/fasciculata) and inner (reticularis) zones of the adrenal cortex of the guinea pig to examine the relation between cholesterol content and LDL receptor activity. While the concentration of cholesterol was 2-3-times higher in the outer cortical zone, the maximum high-affinity binding capacity for LDL was essentially the same for the two zones, or slightly higher for the inner zone. Adrenocorticotrophic hormone (ACTH) caused a significant increase in LDL receptor activity only in the outer zone, but led to a reduction in the cholesterol content in both adrenocortical zones. The treatment of animals with 17 alpha-ethinyl-estradiol also resulted in a reduction of cholesterol in both adrenocortical zones, but an increase in LDL receptor number only in the outer zone. The latter effect was partially reversed by the administration of dexamethasone. Aminoglutethimide, which was used in a dose that did not block steroidogenesis but did block the hydrolysis of cholesteryl esters in response to ACTH, did not prevent the ACTH-induced increase in LDL receptor number in the outer zone. Thus, the number of LDL receptors was increased in the zona fasciculata by ACTH in the absence of a reduction in cellular cholesterol content, while the number of LDL receptors in the zona reticularis was not increased by ACTH even in the face of a reduction in cellular cholesterol. Exclusive of the experiments employing aminoglutethimide, when the cellular cholesterol content was plotted against LDL binding activity, an excellent inverse correlation was revealed for the zona fasciculata, but essentially no correlation was noted for the zona reticularis. It is concluded that the outer and inner cortical zones of the guinea pig adrenal are quite distinct in the nature of their LDL receptor activity and regulation: the LDL receptor of the outer zone appears to function in a way similar to what has been reported for the whole adrenal cortex of other species in that receptor number correlates with tissue cholesterol content and is primarily regulated by ACTH; the LDL receptor number of the inner zone, however, does not correlate with tissue cholesterol content and is apparently not regulated by ACTH.  相似文献   

19.
Adrenal ferredoxin, the iron-sulfur protein associated with cytochromes P-450 in adrenocortical mitochondria, has been localized immunohistochemically at the light microscopic level in rat adrenals by employing rabbit antiserum to bovine adrenal ferredoxin in both an unlabeled antibody peroxidase-antiperoxidase method and an indirect fluorescent antibody method. When sections of rat adrenals were exposed to the adrenal ferredoxin antiserum in both procedures, positive staining for adrenal ferredoxin was observed in parenchymal cells of the three cortical zones but not in medullary chromaffin cells. Marked differences in the intensity of staining, however, where observed among the three cortical zones: the most intense staining being found in the zona fasciculata, less in the zona reticularis, and least in the zona glomerulosa. Furthermore, differences in staining intensity were also observed among cells within both the zona fasciculata and the zona reticularis. In agreement with these immunohistochemical observations, determinations of adrenal ferredoxin contents by electron paramagnetic resonance (EPR) spectrometry in homogenates prepared from capsular and decapsulated rat adrenals revealed that the concentration of adrenal ferredoxin in the zona glomerulosa was lower than that in the zona fasciculata-reticularis. Similar results were obtained when the contents of cytochrome P-450 were determined in capsular adn decapsulated rat adrenal homogenates. These observations indicate that adrenal ferrodoxin and cytochrome P-450 are not distributed uniformly throughout the rat adrenal cortex.  相似文献   

20.
This paper reports a quick, relatively simple and reproducible technique for obtaining populations of zona fasciculata and zona glomerulosa cells up to 80-90% pure, which can be maintained in vitro for study of adrenocortical cell function. Isolated guinea pig adrenocortical cells were separated on a 1-28% bovine serum albumin/Ca++, Mg++-free buffer gradient (wt/vol at 4% increments) using equilibrium density centrifugation (570 g, 30 min). Over 60% of the 8 x 10(5) viable cells/adrenal obtained in the total isolate were recovered after separation. 80% of the zona glomerulosa cells were found in the lower three bands of the gradient. 78% of the zona fasciculata cells were found in the top three bands. Of the cells in the first two bands, 78-91% were zona fasciculata cells, whereas of the cells in the bottom two bands 92-95% were zona glomerulosa cells. The cells retained the morphological characteristics of cells in situ and could be maintained in vitro for periods up to 11 d. They produced a wide variety of steroids, cortisol, corticosterone, aldosterone, 11-beta- hydroxyandrostenedione, deoxycortisol, deoxycorticosterone, cortisone, 18-hydroxycorticosterone, and a product tentatively identified as dehydroepiandrosterone, and they responded to ACTH in a dose-responsive manner with enhanced levels of steroid output. Zona glomerulosa- enriched populations differed from zona fasciculata-enriched populations in their abundant production of aldosterone and in the pattern of steroid production. None of the cultures responded to angiotensin II (100 pg/ml) with increased steroid production.  相似文献   

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