Response of adrenal 3beta-hydroxy-delta5-steroid dehydrogenase to adrenocorticotropin treatment in thiouracil-fed male mice

A number of parallels can be drawn between the reported endocrine status of thiouracil-fed young rodents and that of aged animals, particularly with regard to the hypothalamus-pituitary-adrenal axis. Since the activity of the adrenal steroidogenic enzyme 3beta-hydroxy-delta5-steroid dehydrogenase (3beta-HSD) has been shown to be depressed in aged rats and mice, the present study was done to determine whether exposure of young mice to thiouracil had a similar effect on adrenal 3beta-HSD activity. Feeding the goitrogen thiouracil at 0.25% (w/w) of the maternal diet from conception, and keeping it 0.25% of the offsprings' diet after weaning, significantly elevated activity of 3beta-HSD per gram of adrenal gland above control levels in 4-month-old mice, perhaps to compensate for depressed adrenal mass. Daily subcutaneous injections of physiological saline (0.9%) for 4 days was sufficient to increase 3beta-HSD activity per gram of adrenal tissue in euthyroid (P less than 0.05) but not in thiouracil-fed mice. Subcutaneous administration of ACTH (2 IU daily for 4 days) significantly increased adrenal 3beta-HSD activity to comparable levels in thiouracil-fed and euthyroid animals. Thus, thiouracil enhances the activity of 3beta-HSD per gram of adrenal tissue and does not prevent response of enzyme activity to exogenous ACTH.     

Light and electron microscopic immunocytochemistry on the localization of 3 beta-hydroxysteroid dehydrogenase/isomerase in the bovine adrenal cortical cells

The localization of 3 beta-hydroxysteroid dehydrogenase/isomerase (3 beta-HSD) was studied in bovine adrenal glands by light as well as electron microscopic immunocytochemistry, using anti-bovine adrenal 3 beta-HSD antibody. With light microscopy the cytoplasm of the glomerulosa cells was weakly immunostained, while that of the fasciculata-reticularis cells was intensely immunostained though both the capsular connective tissue cells and the medullary cells were entirely negative for this reaction. Electron microscopic immunocytochemistry revealed that the positive reaction products for 3 beta-HSD were present on the membrane of smooth endoplasmic reticulum of the cortical cells, especially that of the fasciculata and reticularis cells. Other cell organelles such as mitochondria and Golgi apparatus were entirely negative. The present results indicate that 3 beta-HSD is present in the membrane of smooth endoplasmic reticulum of bovine adrenal cortical cells.     

Effect of biseptol on the adrenal cortex of the white rat in postoperative shock

The study aimed to find out the effect of sulfonamide combined with Trimetaprim-Biseptol 480 on the adrenal cortex in post-operative shock after removal of SPIGELian lobe (lobectomy of the lobus caudatus and unilaterally of one kidney with its suprarenal gland. The study was performed on a material of white rats which were post-operatively administered Biseptol 480 in doses 5 times bigger than those given to men. It was attempted to determine histochemically the intensity of the adrenal cortex' function by testing the number of lipid droplets, activity of the main enzyme of steroidogenesis (beta-hydroxy steroid dehydrogenase) and the level of alpha-ketols (as the final stage of steroidogenesis). Pathomorphologic examinations were also performe. On the basis of the present study's results, it was observed that - in the case of liver-lobectomy - the zona fasciculata and zona reticularis are functionally stimulated but the zona glomerulosa becomes insufficient. In the case of nephrectomy plus suprarenal gland's removal, all the adrenal cortex becomes insufficient. Administration of Biseptol in the 1st case contributed to hormonal inactivation of the zone glomerulosa cells, but in the 2nd case, it caused an increased activity of steroid dehydrogenase and an increase of the alpha-ketol level in the zona fasciculata.     

The dynamics of the histochemical activity of the oxidoreductases in the myocardium of mature and old rats undergoing whole-body gamma irradiation at a dose of 1 Gy

The effect of gamma radiation (1 Gy) on redox enzyme activity in heart cells of adult and old rats was studied during a month following the exposure. It was shown that the activity of diaphorases and succinate dehydrogenase decreased whereas that of other tricarboxylic acid cycle enzymes and lactate dehydrogenase underwent phase changes.     

Functional morphology of the adrenal cortex during the physiological rhythm of sex steroid synthesis]

A method of a quantitative histenzymological analysis was used for determination of the extent of participation of various zones of the adrenal cortex in provision of physiological rhythm of the steroid synthesis. The activity of 3beta-OH-steroid dehydrogenase, glucoso-6-phosphat dehydrogenase, NAD- and NADP-diaphorases, acid and alkaline phosphatases and non-specific esterase was investigated. The data of a histoenzymotological study were compared with the result of biochemical analysis of corticosteroids in the peripheral blood. Under physiological conditions intensification of steroidogenesis was realized by mobilization of individual groups of cells of the adrenal gland, not its whole parenchyma. Physiological rhythm of steroid synthesis was provided by an integrated function of all the zones; however, by duration and quantitative expression of the secretory activity a structural heterogeneity was revealed in the adrenal cortex.     

Steroid hormone production in testis, ovary, and adrenal gland of immature rats irradiated in utero with 60Co

Pregnant rats received whole-body irradiation at 20 days of gestation with 2.6 Gy lambda rays from a 60Co source. Endocrinological effects before maturation were studied using testes and adrenal glands obtained from male offspring and ovaries from female offspring irradiated in utero. Seminiferous tubules of the irradiated male offspring were remarkably atrophied with free germinal epithelium and containing only Sertoli cells. Female offspring also had atrophied ovaries. Testicular tissue obtained from intact and 60Co-irradiated rats was incubated with 14C-labeled pregnenolone, progesterone, 17 alpha-hydroxyprogesterone, and androstenedione as a substrate. Intermediates for androgen production and catabolic metabolites were isolated after the incubation. The amounts of these metabolites produced by the irradiated testes were low in comparison with the control. The activities of delta 5-3 beta-hydroxysteroid dehydrogenase, 17 alpha-hydroxylase, C17,20-lyase, and delta 4-5 alpha-reductase in the irradiated testes were 30-40% of those in nonirradiated testes. Also, the activities of 17 beta- and 20 alpha-hydroxysteroid dehydrogenases were 72 and 52% of the control, respectively. In adrenal glands, the 21-hydroxylase activity of the irradiated animals was 38% of the control, but the delta 5-3 beta-hydroxysteroid dehydrogenase activity was comparable to that of the control. On the other hand, the activity of delta 5-3 beta-hydroxysteroid dehydrogenase of the irradiated ovary was only 19% of the control. These results suggest that 60Co irradiation of the fetus in utero markedly affects the production of steroid hormones in testes, ovaries, and adrenal glands after birth.     

Activity of an NAD-dependent 5,10-methylenetetrahydrofolate dehydrogenase in normal tissue, neoplastic cells, and oncogene-transformed cells

As an extension of the previously reported observation concerning the existence of NAD-dependent 5,10-methylenetrahydrofolate dehydrogenase in transformed cells a variety of tissues and cell lines have been assayed for this activity. This activity was found in all assayed transformed cells. Results with rat liver derived epithelial (RLE) cells transformed with a series of oncogenes (v-raf, v-raf/v-myc (J2), v-myc (J5), and v-Ha-ras (pRNR16)) indicated that expression of activity correlates with the extent of transformation and was independent of the oncogene used for transformation. Compared to previously reported values for normal tissue, surprisingly high levels of the NAD-dependent 5,10-methylenetetrahydrofolate dehydrogenase were found in the rat adrenal cortex. This activity was not seen in mouse or bovine adrenal. Enzymatic activity was also detected in mouse bone marrow and was strain dependent. The levels of activity in mouse bone marrow were lower than previously reported. The NAD-dependent 5,10-methylenetetrahydrofolate dehydrogenase activity in rat adrenal and RLE cells may represent tools for studying the regulation of expression of this activity.     

Adrenal glucocorticoid function and cytoplasmic dehydrogenase activity in the presnece of mechanical and toxic liver damage]

Against the background of low steroid metabolism in the liver there was noted some decrease in the rate of corticosterone synthesis by the adrenal gland sections, and also, a decrease in the dehydrogenase activity in the cytoplasm of adrenal cells in male rats 48 hours after partial hepatectomy, as compared to the sham-operated animals. These changes resulted from suppression of the central mechanisms of stress realization due to the lowered steroid metabolism. Intraperitoneal administration of carbon tetrachloride (0.1 ml per 100 g of body weight) at the same periods led to a significant intensification of the steroidogenesis in the adrenal tissue and to the activation of NAD-dependent dehydrogenases in the cytoplasm. The role of toxic injury of the glands in the changes of the functional state of the adrenal cortex cells is discussed.     

Age-related characteristics of postradiation regeneration of the blood system

This study was pursued on hybrid (CBA X C57Bl)F1 mice at the ages of 17 and 27 months irradiated at a dose of 4 Gy. It was shown that the postirradiation recovery of haemopoiesis in old mice was the same as in the young (2-3 month-old), and in some respects (for instance, granulocytic and erythroid cells of the bone marrow, and CFUc) the recovery was even more active exhibiting a period of a pronounced hyperregeneration.     

Changes in the pattern of androgen formation in vitro by the baboon fetal adrenal gland at mid- and late gestation

In the present study, baboon fetal adrenal cells were obtained at mid- and late gestation and incubated for various intervals to determine simultaneously the effects of length of incubation and stage of development on the pattern of adrenal steroidogenesis. Cells were treated with adrenocorticotropic hormone (ACTH) from 0 to 48 h of incubation, and the concentrations of dehydroepiandrosterone (DHA), DHA-sulfate (DHAS), and androstenedione (delta 4A) were determined in the medium. The secretion of DHA and DHAS by untreated or ACTH-treated cells of midgestation increased linearly throughout the 48-h incubation period. In fetal adrenal incubates of late gestation, however, DHA and DHAS concentrations peaked at 3 h and declined thereafter, suggesting that the DHA secreted into the medium was further metabolized by this tissue. Baboon fetal adrenal cells formed similar amounts of DHAS and DHA at midgestation, but greater quantities of DHAS were formed at term. In fetal adrenal incubates of midgestation, DHA concentrations exceeded those of delta 4A by threefold, a relationship which was reversed at late gestation, probably due to the increase in the activity of 3 beta-hydroxy-steroid dehydrogenase with advancing gestation. Because the decline in DHA with time of incubation was also associated with a concomitant decrease in DHAS and no change in delta 4A, it does not appear that formation of these steroids account for the loss of DHA. We conclude that the pattern of androgen metabolism exhibited by fetal adrenal cells obtained at midgestation is different from that at term.(ABSTRACT TRUNCATED AT 250 WORDS)     

Organogenesis of the pituitary, adrenal, and lung at birth in the wallaby, Macropus rufogriseus

The ultrastructure of the pituitary, the adrenal, and the lung was examined in the newborn wallaby, Macropus rufogriseus. Tissue from six wallaby neonates (less than 8 hr of age), two near-term fetuses (26 days after removal of suckling pouch young [RPY]), and a two-day-old pouch young was examined; and tissue levels of cortisol in the adrenal glands of five neonates and a near-term fetus (26 days) were measured by radioimmunoassay. At birth the adenohypophysis comprised the bulk of the pituitary gland. The pars distalis was well vascularized and many cells contained electron-dense, membrane-bound granules. The adrenal glands lacked specific zones but comprised two distinct populations of cells. The cytoplasm of one cell type contained electron-dense, membrane-bound granules, similar to those observed inside catecholamine-secreting cells of the adrenal medulla; the other cell type possessed large amounts of smooth endoplasmic reticulum and mitochondria with tubulo-vesicular cristae. These features are characteristic of cells which are actively synthesizing steroid hormones. The concentration of cortisol was 0.58 ng/adrenal in the wallaby at birth. The fetal lungs near term were at the glandular stage of development, and epithelial differentiation of type I and type II pneumocytes was imminent although attenuation was not evident. The canalicular neonatal lung did not contain true alveoli, but type II pneumocytes contained osmiophilic lamellar inclusions of surfactant. The fetal pituitary and adrenal are functional at birth and are thus capable of initiating parturition and of influencing lung maturation in the fetus.     

NADPH production by the pentose phosphate pathway in the zona fasciculata of rat adrenal gland.

Biosynthesis of steroid hormones in the cortex of the adrenal gland takes place in smooth endoplasmic reticulum and mitochondria and requires NADPH. Four enzymes produce NADPH: glucose-6-phosphate dehydrogenase (G6PD), the key regulatory enzyme of the pentose phosphate pathway, phosphogluconate dehydrogenase (PGD), the third enzyme of that pathway, malate dehydrogenase (MDH), and isocitrate dehydrogenase (ICDH). However, the contribution of each enzyme to NADPH production in the cortex of adrenal gland has not been established. Therefore, activity of G6PD, PGD, MDH, and ICDH was localized and quantified in rat adrenocortical tissue using metabolic mapping, image analysis, and electron microscopy. The four enzymes have similar localization patterns in adrenal gland with highest activities in the zona fasciculata of the cortex. G6PD activity was strongest, PGD, MDH, and ICDH activity was approximately 60%, 15%, and 7% of G6PD activity, respectively. The K(m) value of G6PD for glucose-6-phosphate was two times higher than the K(m) value of PGD for phosphogluconate. As a consequence, virtual flux rates through G6PD and PGD are largely similar. It is concluded that G6PD and PGD provide the major part of NADPH in adrenocortical cells. Their activity is localized in the cytoplasm associated with free ribosomes and membranes of the smooth endoplasmic reticulum, indicating that NADPH-demanding processes related to biosynthesis of steroid hormones take place at these sites. Complete inhibition of G6PD by androsterones suggests that there is feedback regulation of steroid hormone biosynthesis via G6PD.     

Quantitative X-ray microanalysis of adrenal medullary cells of young adult and aged rats after glutaraldehyde fixation and potassium dichromate treatment

X-ray microanalysis has been used to detect chromium in the histochemical reaction product resulting from the reaction of noradrenaline with glutaraldehyde during fixation of the rat adrenal medulla and subsequent treatment with potassium dichromate. In unstained ultrathin sections, noradrenaline cells can be identified by their content of highly electron-dense storage granules, which enables individual granules to be analysed quantitatively to assess the amount of bound chromium within them. In young adult (4-month-old) rats the mean chromium content of noradrenaline-containing adrenal medullary granules was 443.6±50.7 mM/kg dry weight. In aged (24-month-old) animals the mean chromium content was 267.0±64.0 mM/kg dry weight which was significantly (P<0.01) lower then the value for the young adult rats. Some noradrenaline cells contained granule populations, which were markedly less electron dense than those in the young adults and this is reflected in the ranges of chromium values recorded between individual cells in the 24-month-old animals. There were also noradrenaline cells in the medulla of the aged animals, which contained highly electron-dense granules but these did not contain as much bound chromium as the highest values recorded in the young adult animals. The results are discussed in the context of the growth of the rat adrenal medulla throughout the lifespan and with respect to the effects of age on the integrity of storage granules.     

Isoenzyme spectrum of lactate dehydrogenase, malate dehydrogenase, esterase and acid phosphatase of rat brain cells at different times after external 1 Gy gamma irradiation]

The influence of external single gamma-irradiation with a dose of 1 Gy on the isoenzyme composition of lactate dehydrogenase, malate dehydrogenase, esterase and acid phosphatase in the cytoplasm of rat brain cells has been investigated. Irradiation was shown to cause differently directed changes in the ratio of the isoenzymes under study at different times after exposure. The isoenzyme spectrum of lactate dehydrogenase and malate dehydrogenase was shown to be normalized on day 30 after irradiation, whereas the isoform composition of esterase and acid phosphatase was not stabilized at that time.     

Adrenal growth and ontogeny of adrenal substance P, enkephalins and catecholamines in the ovine fetus

Biologically active peptides have been identified in the adrenal glands of several adult mammalian species. Some of these peptides appear to modulate the nicotine-induced catecholamine release from the adrenal medulla. The present study was carried out to investigate the presence and ontogeny of the peptides substance P, met-enkephalin and leu-enkephalin in the ovine fetal adrenal gland from 70 to 140 days gestation (term = 145-150 days). Concurrently, the growth of the fetal adrenal as well as the gestational changes in catecholamine content were determined. The maternal adrenal glands were also studied for comparison. The ovine fetal adrenal gland increased in weight with advancing gestation at a single exponential rate. Total adrenal substance P content correlated with gestational age, while met-enkephalin, leu-enkephalin and total catecholamine contents correlated with adrenal weight. The adrenal content (normalized as per unit protein) of substance P was highest in the young fetuses at 70 days gestation, decreased progressively towards term and, in the adult levels were significantly lower than those measured in the fetuses. The contents of met-enkephalin and leu-enkephalin were low in the young fetuses at 70 days gestation, but reached high levels at 130 to 140 days gestation. Maternal adrenal contents of the two enkephalins were significantly lower than those measured in the near-term fetal adrenal. Total catecholamine content in the fetal adrenal medulla increased as the fetus matured. Norpinephrine was the primary catecholamine present in the medulla of fetuses at 70 and 80 days gestation, while epinephrine was the major one in the adult.(ABSTRACT TRUNCATED AT 250 WORDS)     

Change in the succinate dehydrogenase activity of peripheral lymphocytes in the rat in early periods following exposure to ionizing radiation

Activity of succinate dehydrogenase (SDH) in peripheral blood lymphocytes of albino mongrel rats was determined during an hour following gamma-irradiation. The highest SDH activity in blood lymphocytes (a 41 per cent increase) was registered 20-30 min following 75 Gy irradiation of the head. With a dose of 20 Gy the SDH response was twice as low. During 1 h following irradiation with a dose of 200 Gy the SDH activity exhibited a 10 per cent decrease.     

Ovine prolactin potentiates the action of adrenocorticotropic hormone on the secretion of dehydroepiandrosterone sulfate and dehydroepiandrosterone from cultured bovine adrenal cells

To determine the direct effect of prolactin on adrenal androgen secretion, the daily secretions of dehydroepiandrosterone sulfate (DHEA-S), dehydroepiandrosterone (DHEA), androstenedione and cortisol were determined in monolayer culture of bovine adrenal cells in the presence or absence of adrenocorticotropic hormone (ACTH) and/or prolactin. In the absence of ACTH ovine prolactin alone had no effect on steroid secretion during seven-day culture. Ovine prolactin, when administered in combination with ACTH, significantly potentiated the stimulatory effect of ACTH on DHEA-S and DHEA but not androstenedione secretion on the seventh day in culture. On the first day in culture prolactin showed no synergistic effect with ACTH on DHEA and DHEA-S secretion, although ACTH significantly increased DHEA and cortisol secretion. DHEA-S secretion increased as a function of prolactin concentration in the presence of ACTH. These results indicated that long-term treatment by ovine prolactin with ACTH caused the increase in adrenal androgen secretion from bovine adrenal cells. The site of action of prolactin was suggested to be the partial inhibition of adrenal 3 beta-hydroxysteroid dehydrogenase by the result of increases in DHEA-S and DHEA but not androstenedione secretion.     

Histochemical studies on the adrenal glands of the marmosets (Callithrix jacchus and Callithrix penicillata).

The histrochemistry of the adrenal glands was studied in four adult male marmosets (two Callithrix jacchus and two Callithrix penicillata). It was impossible to demonstrate any reactivity to UDPG-GT, ADH, alanyl aminopeptidase, leucine aminopeptidase, xilitol (NAD-dependent) dehydrogenase, beta-glucuronidase and aryl-sulfatase in these glands. Total phosphorylase was found in scattered cells of the glomerulosa and adjacent outer fasciculata of one C. penicillata. The dehydrogenases (LDH, G-6-PDH,6-PGDH, NADPH2-TR,ICDH,SDH,NADH2-TR, alpha-GPDH, beta-OHBDH) as well as the hydrolases (except alkaline phosphatase, ATPase, and acetylcholinesterase) showed a stonger reactivity in the cortical part. Some hydrolases (naphthol acetate esterase, acid phosphatase) and cytochrome oxidase were less reactive in the zona glomerulosa, where the dehydrogenases were more abundant. The outer fasciculata and the reticularis also showed a strong dehydrogenase reactivity.     

Dehydroepiandrosterone and dehydroepiandrosterone sulfate production in the human adrenal during development and aging.

Dehydroepiandrosterone (DHEA) is produced in prodigious quantities by the human adrenal, principally as the 3-sulfoconjugate DHEA sulfate (DS) during intrauterine life. The fetal zone and neocortex cells of the fetal adrenal express large amounts of DHEA sulfotransferase and minimal amounts, at least until very near the end of gestation, of 3beta-hydroxysteroid dehydrogenase. This pattern of enzyme expression favors substantial secretion of DHEA/DS with minimal cortisol produced; the DHEA/DS serves as the major precursor for placental estrogen formation in human pregnancy. Aside from adrenocorticotropin, other physiologic regulators of growth and steroidogenesis in the fetal adrenal have been postulated to exist, but have yet to be identified. Whereas intrauterine stressors may activate adrenal cortisol secretion, the fetal adrenal responds to many pregnancy conditions by suppressing DHEA/DS formation. After birth, the human adrenal undergoes reorganization whereby the large, inner fetal zone regresses, and DHEA/DS production is diminished. Just prior to gonadal maturation, the human adrenal undergoes morphologic and functional changes (adrenarche) that give rise to a prominent zona reticularis that is characterized by the presence of DHEA sulfotransferase, the absence of 3beta-hydroxysteroid dehydrogenase, and an enhancement of DHEA/DS production. The adrenal of the adult responds to stress in many instances like that of the fetus: increased cortisol secretion and diminished DHEA/DS secretion. The mechanisms for this divergence in the adrenocortical pathway is unknown. With aging, there is suppression of DHEA/DS secretion, possibly as the consequence of an involution of the zona reticularis, but corticosteroid production continues unabated.     

The role of initial state of adrenal cortex in external irradiation effects upon its structure, function and androgen-receptor interactions

We studied morphological-biochemical time-course reactions of adrenal cortex and hormonal function of testicles after combined or separate actions of external radiation exposure (1.0 Gy at 7.8 x 10(-4) Gy/sec) and prolonged (12-, 32 days) subcutaneous corticosterone injections (10 mg/kg/animal) in 2-3-month old male rats. Both variants with exogenous hormone depressed endogenous glucocorticoid production and evolved acute structure-functional adrenal gland cortex deficiency. Radiocensitivity of the gland at the experimental conditions was increased. Simultaneously the aggravation of adrenal cortex functional activity accompanied with hypogonadism and depressed reproductive potential of male rats, accessed by means of androgen status and androgenspecific (transporting and receptional) proteins characteristics as sensitive molecular markers of an animal possible fecundity.