Adrenal Cortical Activity Research Articles

Effect of antioxidants supplementation on plasma hormonal profiles in Hallikar cattle during different seasons

Present study was carried out to ascertain the influence of different seasons on hormonal profiles in Hallikar cattle. Two groups (control and supplemented) of healthy female Hallikar cattle with six animals in each group selected from Madabal Village of Ramanagara District, Karnataka, India, were utilized for the present study. Selected animals were exposed to environmental stressors during three different seasons (winter, summer and rainy) by allowing them for grazing daily. Animals of control group received no supplementation but supplemented group received oral supplementation of vitamin E and selenium, during the study period. Blood samples collected from all the animals at monthly interval during three different seasons were processed to obtain the plasma which were stored at - 80 ºC until they are utilized for determination of hormones like triiodothyronine (T3), thyroxine (T4), insulin and cortisol using radioimmunoassay technique. In the present study, triiodothyronine and thyroxine levels reduced significantly (P less than 0.05) during summer season compared to other seasons in control group animals. In both control and supplemented group, plasma insulin levels declined significantly (P less than 0.05) and plasma cortisol levels increased significantly (P less than 0.05) during summer compared to other seasons. Form the study, it was concluded that the summer stress reduces the thyroid and pancreatic activity leading reduced secretion of thyroid hormones and insulin. Further, the summer stress stimulates the adrenal cortical activity leading to enhanced secretion of the cortisol in Hallikar cattle

An Exploratory Study to Assess the Impact of Work Demands and the Anticipation of Work on Awakening Saliva Cortisol

The goal was to investigate whether cortisol on awakening is higher on Monday relative to Sunday morning, and to assess whether responses vary with job demands and the anticipation of work. 77 white collar workers gave a sample of saliva on awakening Sunday and Monday mornings, and then rated their anticipation for work. Data showed that salivary cortisol concentration was greater on Monday compared to Sunday morning. There were no main effects of job demands or anticipation of work on cortisol secretion. There was a significant interaction between job demands and anticipation of work on Monday, relative to Sunday morning. Cortisol secretion was higher in those reporting high job demands together with a greater anticipation of work. It was concluded that increased awakening saliva cortisol secretion is not necessarily a result of working in a highly demanding environment. Anticipating the impending working day appears to be an important influence on adrenal-cortical activity.

Induction drug and outcome of patients admitted to the intensive care unit after emergency laparotomy

Etomidate is often used to induce anaesthesia in sick patients owing to its relative cardiovascular stability. However, etomidate affects adrenal cortical activity, and there is concern that this could impair outcome in patients undergoing emergency surgery. We retrospectively analysed data from 176 patients admitted to an ICU after emergency laparotomy. We retrieved ASA status, surgical diagnosis, induction drug use, blood pressure before and after induction and any vasopressor administration, steroid and vasopressor therapy in ICU and patient outcome. Choice of induction drug was at the discretion of the attending anaesthetist. The drugs (numbers of patients) used to induce anaesthesia were etomidate (52), thiopental (90), propofol (16), midazolam (12) and ketamine (4). Fifty-two patients (30%) died in hospital. ASA status was the only independent predictor of hospital outcome (P < 0.001). Choice of induction drug was related to ASA status. As ASA status worsened, the likelihood of using etomidate or midazolam/ketamine increased (P = 0.001). We found no association between etomidate and dying in hospital, though our study might not have had sufficient power to show a difference between induction drugs. The relative risks [95% confidence interval (CI)] of dying in hospital were etomidate 1.16 (0.72-1.87), thiopental 0.82 (0.52-1.30), propofol 0.40 (0.11-1.49) and midazolam/ketamine 1.84 (1.09-3.12). Vasopressor and steroid therapy in the ICU was not related to induction drug. The risk of developing hypotension at induction or of receiving vasopressor to treat hypotension was least with etomidate. We found no evidence that etomidate is associated with worse outcome than thiopental or propofol in patients undergoing emergency laparotomy, but we cannot be certain that etomidate is well tolerated in this group of patients. More data are required to address this issue definitively.

Strain differences in proliferation of progenitor cells in the dentate gyrus of the adult rat and the response to fluoxetine are dependent on corticosterone

This paper investigates the role of differences in adrenal cortical function on the proliferation rate of progenitor cells in the dentate gyrus of the hippocampus in adult Sprague–Dawley (SD) and Lister-Hooded (LH) male rats. SD rats had around 60% more cells labeled with Ki67 (an index of mitosis) than LH rats under basal conditions. Bilateral adrenalectomy (ADX) increased levels in both strains, but by unequal amounts, such that post-ADX numbers of Ki67-labeled cells were similar in both strains. Daily injections of 5 mg/kg corticosterone for 7 days reduced levels to similar values in ADX rats of both strains. The activity of progenitor cells in either strain did not respond to daily i.p. injections of fluoxetine (10 mg/kg) for 14 days, but an equivalent dose administered by osmotic minipump stimulated proliferation in both by a similar proportional amount, such that strain differences persisted. S.c. implantation of a corticosterone pellet (75 mg), which flattens the diurnal rhythm in corticosterone, prevented fluoxetine delivered by minipump from activating progenitor cell mitosis in SD rats, as it had in the LH strain in a previous study. These results show that much, if not all, of the marked strain differences between SD and LH rats in progenitor cell activity, and hence rates of neurogenesis in the dentate gyrus may be ascribed to corresponding differences in adrenal cortical activity.

Adaptive Processes in the Respiratory System and Adrenals in Concomitant Brain Injury

Objective: to study the nature and time of development of pulmonary and adrenal structural changes in early concomitant brain injury. Materials and methods. The lungs and adrenals from 120 persons who had died from severe concomitant brain injury were morphologically studied. Pulmonary and adrenal specimens were embedded in paraffin. Histological sections were stained in hematoxylin-eosin, by using the procedures developed by Weigert, van Gieson, and Mallory. The Schick test and other histochemical methods were used. Morphometric studies were also employed. Statistical processing used Student’s t-test. Results. In injury, the early pulmonary structural changes were ascertained to be circulatory disorders, bronchial and bronchiolar mucosal damage, and the development of atelectases and focal emphysema. The morphological criteria for increased adrenal cortical functional activity are focal delipidization, diminished cortical transparency, the «spotty» appearance of the cortex, boundary-spanning between the cortical and reticular zones, multiple cytolysis, and iron plethora. Conclusion. Severe concomitant brain injury is followed by pulmonary structural changes underlying acute respiratory failure. Adrenal structural and functional changes play an important role in the pathogenesis of lung injury. Key words: severe concomitant brain injury, lung injury, adrenals.

Effect of corticosterone administration on mammary gland development and p27 expression and their relationship to the effects of energy restriction on mammary carcinogenesis.

The inhibitory activity against mammary carcinogenesis mediated by energy restriction is accompanied by a reduction in the degree of mammary ductal branching, and an increase in adrenal cortical activity. Levels of p27/kip1 protein, a gene product associated with cell cycle growth arrest, have also been shown to be elevated in mammary epithelium and in mammary lesions of energy-restricted animals. Based on these data we have proposed that increased secretion of adrenal cortical steroids accounts, in part, for the effects of energy restriction. In this experiment the hypothesis tested was that corticosterone administration would mimic the effects of energy restriction, both on mammary gland development and on levels of p27 protein in mammary ductal epithelium. To test this hypothesis corticosterone was fed to female rats for 4 weeks. Dietary corticosterone increased serum and urinary corticosterone levels in a dose-dependent manner (P < 0.01). The effects of corticosterone treatment on mammary gland development were analyzed digitally; p27 protein was detected immunohistochemically. The ductal extension and branching of the mammary gland were reduced in a dose-dependent manner by corticosterone treatment (P < 0.05); however, the magnitude of the effect was greater on ductal branching. Overall, increasing dietary corticosterone reduced the total volume of mammary epithelium in a dose-dependent manner, an effect that remained even after adjustments for differences among animals in body mass. Consistent with this effect, the amount of p27 protein present in ductal mammary epithelial cells increased dose-dependently in response to increasing corticosterone administration (P < 0.01). The hypothesis is proposed that dietary administration of corticosterone may imitate the effects of energy restriction on mammary carcinogenesis by regulation of mammary tissue size homeostasis via p27/kip1 mediated arrest of cell cycle progression.

Differential effects of fat and sucrose on the development of obesity and diabetes in C57BL/6J and [formula omitted] mice

We have previously demonstrated that the C57BL/6J ( B 6J ) mouse will develop severe obesity, hyperglycemia, and hyperinsulinemia if weaned onto a high-fat, high-sucrose (HH) diet. In the present study, we compared the effects of fat and sucrose separately and in combination on diabetes- and obesity-prone B 6J and diabetes- and obesity-resistant A J mice. After 4 months, the feed efficiency ([FE] weight gained divided by calories consumed) did not differ across diets in A J mice, but B 6J mice showed a significantly increased FE for fat. That is, B 6J mice gained more weight on high-fat diets without consuming more calories than A J mice. The increase in FE was related to adipocyte hyperplasia in B 6J mice on high-fat diets. Fat-induced obesity in B 6J mice was unrelated to adrenal cortical activity. In the absence of fat, sucrose produced a decreased in FE in both strains. Animals fed a low-fat, high-sucrose (LH) diet were actually leaner than animals fed a high—complex-carbohydrate diet. Fat was also found to be the critical stimulus for hyperglycemia and hyperinsulinemia in B 6J mice. In the absence of fat, sucrose had no effect on plasma glucose or insulin. These data clearly show that across these two strains of mice, genetic differences in the metabolic response to fat are more important in the development of obesity and diabetes than the increased caloric content of a high-fat diet.

Lack of coupling between adrenal cortical metabolic activity and blood flow in anesthetized dogs

Pages H410–H415: N. T. Sakima, M. J. Breslow, H. Raff, and R. J. Traystman. “Lack of coupling between adrenal cortical metabolic activity and blood flow in anesthetized dogs.” Page H412: The units for oxygen consumption in Fig. 3 should read as cc O2/min/100 g adrenal gland.

Stimulation by voluntary exercise of adrenal glucocorticoid secretion in mature female hamsters

The possibility that habitual voluntary running induces a chronic change in adrenal glucocorticoid synthesis and secretion was examined in freely running mature female hamsters, in whom this behavior accelerates growth, reduces body fat levels, and elevates core temperature. Hamsters were free to run on horizontal discs or in vertical wheels between 32 and 80 days, in 14L:10D or in 10L:14D photoperiods, and at the end of this period, corticosterone and cortisol steroidogenesis and serial plasma corticosterone concentrations during day and night were used as measures of the chronic stimulation of adrenal cortical activity. Habitual voluntary running significantly increased steroidogenesis of both glucocorticoids and plasma corticosterone concentrations and alone accounted for all the variance in enhanced synthesis and secretion of corticosterone. Acute exercise and/or the nocturnal phase of circadian period enhanced the chronic stimulatory effects of exercise on cortiol. Despite its voluntary and apparently stress-free nature, running induces chronic increases in basal glucocorticoid secretion in mature female hamsters. Putative oversecretion of corticotropin releasing factor in freely running hamsters could account for increased steriodogenesis, acceleration of growth, reduced body fat levels, and core temperature elevation.

Lack of coupling between adrenal cortical metabolic activity and blood flow in anesthetized dogs

Pages H410–H415: N. T. Sakima, M. J. Breslow, H. Raff, and R. J. Traystman. “Lack of coupling between adrenal cortical metabolic activity and blood flow in anesthetized dogs.” Page H412: The units for oxygen consumption in Fig. 3 should read as cc O2/min/100 g adrenal gland.

Lack of coupling between adrenal cortical metabolic activity and blood flow in anesthetized dogs

Pages H410–H415: N. T. Sakima, M. J. Breslow, H. Raff, and R. J. Traystman. “Lack of coupling between adrenal cortical metabolic activity and blood flow in anesthetized dogs.” Page H412: The units for oxygen consumption in Fig. 3 should read as cc O2/min/100 g adrenal gland.

Lack of coupling between adrenal cortical metabolic activity and blood flow in anesthetized dogs.

To determine whether adrenal O2 consumption and cortical blood flow (CBF) increase during stimulation of cortical secretory activity, exogenous adrenocorticotrophic hormone (ACTH) was infused at 0, 2, and 10 ng.kg-1.min-1 (groups 1, 2, and 3, respectively) into dexamethasone-pretreated, pentobarbital-fentanyl-anesthetized, ventilated dogs. ACTH levels of approximately 20, 100, and 500 pg/ml were obtained in groups 1, 2, and 3, respectively. Cortisol secretion increased after 20 min in groups 2 and 3 (from 0.016 +/- 0.004 to 2.25 +/- 1.36 and from 0.02 +/- 0.01 to 5.32 +/- 1.23 microgram.min-1.g cortex-1, respectively) while adenosine 3',5'-cyclic monophosphate (cAMP) secretion increased after 20 min only in group 3 (from 5.7 +/- 2.8 to 61.3 +/- 18.6 micrograms.min-1.g cortex-1). Whole adrenal gland O2 consumption increased after 20 min in group 3 animals (from 0.89 +/- 0.16 to 1.77 +/- 0.27 ml O2.min-1.100 g tissue-1) but not in the other two groups. CBF measured with radiolabeled microspheres was unaffected by ACTH infusion while O2 extraction increased from a baseline of 5.9 +/- 1.4 to 13.0 +/- 2.4% after 30 min in group 3. These data demonstrate that in anesthetized dogs increases in adrenal cortical secretory activity are associated with increases in O2 consumption, and this increase in O2 consumption is met by increasing O2 extraction, not by increasing cortical blood flow.

Effects of nitrofurans on adrenal cortical tissue in chickens

In chicken adrenal glands, aspartate transaminase (AST) activity is concentrated in the adrenal cortical cells. Administration of a bolus dose of furazolidone (200 mg/kg) to the birds produced a decrease in AST activity in the adrenal glands and a general disorganization in the ultrastructure of the adrenal cortical cells. Many adrenal cortical mitochondria appeared to be moribund, being swollen, without cristae or apparently empty. These effects preceded atrophy of the adrenal cortical tissue, which was most marked in the central part of the adrenal glands. The atrophy was still present after 12 weeks, and it is therefore suggested that nitrofurans may be useful in the treatment of Cushing's disease in other animal species. When furazolidone or furaltadone was given in the diet at therapeutic levels, blebs of an electron-dense substance developed in adrenal cortical mitochondria and AST activity in the adrenal glands was reduced. These effects were found to be reversible, and the treatments did not produce atrophy of the adrenal cortical tissue.

Serum Dehydroepiandrosterone and Cortisol Concentration in the Maternal-Fetoplacental Hormonal System in Elective Caesarean Section and Spontaneous Vaginal Delivery in the 28th to 36th and 40th Weeks of Pregnancy

The authors compared the serum DHAS and cortisol level in 53 vaginal deliveries with those of 21 caesarean sections prior to the onset of labour at the 28th to 36th weeks. They also compared 18 vaginal deliveries with 16 elective caesarean sections at the 40th week. The serum hormone concentrations were measured in the maternal vein, the umbilical vein and the umbilical artery. The results indicate that the serum DHAS and cortisol level was higher after vaginal delivery than after caesarean section in the maternal vein, umbilical vein and umbilical artery at the 28th to 36th and also at the 40th week. The authors suggest that, although the role of the fetal adrenal cortex is not so definitive as in the case of some species in the onset of labour, it may be presumed that the increase in adrenal cortical activity cannot be explained exclusively by maternal stress.

Twenty-four hour urinary cortisol and catecholamine excretion in combat-related posttraumatic stress disorder

Heightened adrenal cortical activity is a classic component of the stress response. Elevation of 24-hr excretion of urinary-free cortisol (UFC) has been documented in depressive disorder. We measured 24-hr UFC and catecholamine excretion in ambulatory Vietnam veteran PTSD patients and mentally healthy combat controls

Wild mice in the cold: some findings on adaptation.

The house mouse, Mus domesticus, can thrive in natural environments much below its optimum temperature. Thermogenesis is then above that at more usual temperatures. In addition, body weight, and the weights of brown adipose tissue and the kidneys, may be higher than usual. In free populations of house mice cold lowers fertility and may prevent breeding. Other possible limiting factors on breeding are food supply, shelter for nesting and social interactions. In captivity, wild-type house mice exposed to severe cold (around 0 degrees C) at first adapt ontogenetically by shivering and reduced activity. But raised thermogenesis is soon achieved without shivering; nest-building improves; and readiness to explore may be enhanced. Endocrine changes probably include, at least initially, a rise in adrenal cortical activity and in catecholamine secretion. Some females become barren, but many remain fertile. The maturity of fertile females is, however, delayed and intervals between births are lengthened; nestling mortality rises. A limiting factor during lactation may be the capacity of the gut. Similar adaptive changes are observed during winter in some species of small mammals that do not hibernate. But neither the house mouse nor other species present a single, universal pattern of cold-adaptation. Wild-type mice bred for about 10 generations in a warm laboratory environment (20-23 degrees C) change little over generations. In cold they become progressively heavier and fatter at all ages; they mature earlier, and nestling mortality declines. The milk of such 'Eskimo' females is more concentrated than that of controls. If 'Eskimo' mice are returned to a warm environment, they are more fertile, and rear heavier young, than controls that remained in the warm. Despite the heavier young, litter size is not reduced: it may be increased, probably as a result of a higher ovulation rate. Parental effects have been analyzed by cross-fostering and hybridizing. Survival, growth and fertility are all favourably influenced by the intra-uterine and nest environments provided by 'Eskimo' females. 'Eskimo' males are also better fathers. Hence after ten generations the phenotype of cold-adapted house mice shows the combined effects of (a) an ontogenetic response to cold, (b) a superior parental environment and (c) a change genotype. The secular changes in the cold that lead to this phenotype give the appearance of evolution in miniature; but it is equally possible that they represent a genetical versatility that allows rapid, reversible shifts in response to environmental demands.(ABSTRACT TRUNCATED AT 400 WORDS)

The effects of ACTH, prednisolone and Escherichia coli endotoxin on some clinical haematological and blood biochemical parameters in dwarf goats.

ACTH (microgram kg-1 i.v.) and prednisolone (1 microgram-1 i.v.) caused a moderate but statistically significant inhibition of rumen contractions, whereas no effects on heart rate and body temperature were observed. Both hormones induced hyperglycaemia and leucocytosis, characterised by moderate lymphopenia and a profound increase in the number of circulating neutrophils. A significant decrease in plasma iron and increase in plasma zinc concentrations were observed. After 3 daily i.m. injections of ACTH (10 micrograms-1 day-1) decreases were seen in both serum Alkaline phosphatase (ALP) activity and plasma trace metal concentrations; heart rate was significantly higher. Intraveneous injection of E. coli endotoxin (0.1 microgram kg-1) caused shivering, fever, inhibition of rumen contractions, changes in heart rate, lymphopenia, neutropenia followed by neutrophilic leucocytosis, hypoferraemia, hypozincaemia, hypoglycaemia and a decline in serum ALP activity. ACTH, given i.m. for 3 days, reduced the febrile responses to E. coli endotoxin, modified the changes in heart rate, intensified the inhibition of rumen contractions, and induced a more marked decrease in the number of circulating neutrophils. ACTH pretreatment did not affect the endotoxin-induced decrease in blood glucose concentrations nor the drop in plasma zinc and iron values. These results suggest that glucocorticosteroids are not primarily involved in the fall in plasma iron and zinc concentrations during E. coli endotoxin-induced fever, the effects of endotoxin released glucocorticosteroids on white blood cells and blood glucose are masked by some other effect(s) of endotoxin, and in dwarf goats, ACTH has antipyretic properties without influencing normal body temperature. This effect is probably not dependent on adrenal cortical activity.

Effects of social factors on adrenal weight and related physiology of Macaca fascicularis

Increased adrenal cortical activity and hypertrophy of adrenal glands associated with defeat and social subordination have been reported frequently in small mammals; these adrenal changes have been linked to impairments in immune response, glucose metabolism and reproductive performance. Similar studies in primates have produced variable results. The current study was undertaken to illuminate the effects of social status on the adrenal gland and to examine concurrent effects of social variables on other physiological systems in Macaca fascicularis, in an initial exploration of the hypothesis that high and low social status have different physiological consequences [18]. Sixty adult male M. fascicularis were housed in social groups of n=5, under either stable or unstable social conditions. It was found that subordinate animals had heavier adrenal glands and somewhat higher plasma glucose concentrations than dominants. In contrast, dominants had higher blood pressure and worsened atherosclerosis, under some conditions, than subordinates. These data appear to offer preliminary support for Henry and Stephen's hypothesis of differential arousal of dominant and subordinate animals.

Seven different digoxin immunoassay kits compared with respect to interference by a digoxin-like immunoreactive substance in serum from premature and full-term infants.

Seven different digoxin immunoassay kits showed cross reactivity with an endogenous digoxin-like immunoreactive substance consistently present in serum of neonates, whether premature or full-term. The degree of interference, in decreasing order was: NML greater than New England Nuclear greater than Bio-Rad greater than Clinical Assays greater than Becton Dickinson greater than Serono greater than Syva (EMIT). More recently purchased NML kits showed less sensitivity to the substance, evidently reflecting lot-to-lot differences in antibody. A single baseline determination of the substance before digoxin is administered inadequately compensates for this interference, because the interferent concentrations can differ from day to day, with evidence that it may be most concentrated on the fourth to sixth postnatal day. Its concentration in the serum of neonates is unrelated to the concentration of dehydroepiandrostenedione sulfate, an indicator of fetal adrenal-cortical activity.

Effect of chronic light-dark shift stress on the immune response of the rat

During a period of 35 weeks the night-day pattern of inbred Brown Norway female rats was changes weekly by alternating the light-dark (L-D) rhythm. After a period of 2 months, in a number of the animals, the cellular immune response was measured by means of Concanavalin A stimulation of peripheral blood (Con A) and a Popliteal Lymph Node Assay (PLNA). Serum corticosterone, plasma free fatty acids and peripheral leucocytes were determined as well. Seven months thereafter the remaining animals were sacrificed after which adrenal gland weight and spleen weight were established. Additionally, blood glucose and corticosterone were measured (corticosterone in vitro activity as well as the serum level). Both Con A and PLNA showed a significantly decreased immune response in the L-D shift stress group. Adrenal cortical activity measured in vitro as well as in vivo did not show any significant changes, neither at 2 months nor at 9 months. Therefore, the observed immunosuppressive effect of chronic light-dark shift stress can not be explained by an increased adrenal cortical activity. Other possible explanations for the effect of the light-dark shift stress on the immune response are discussed.