High-fat/high-carbohydrate-diet short- and middle-term effects on gerbil adrenal zona fasciculata histology.

The adrenals synthesize many hormones involved in the regulation and maintenance of homeostasis. To understand the pathophysiological changes during the development of obesity, a histological study of the adrenal was performed in gerbils receiving a high-fat/high-carbohydrate-diet (HFC) for 8 or 12 weeks. Compared to the controls, the HFC diet increased body weight. Our results reveal significant weight and structural changes in the HFC group's adrenal glands (confirmed by gray level co-occurrence matrix texture and fractal analysis), disorganization of zona fasciculata (8 weeks) and hyperplasia and peri-capillary fibrosis (12 weeks). In conclusion, these results show that an HFC induces time-dependent structural lesions of the adrenals in gerbils, which could be a sign of chronic adaptation of these glands.

A Rat Model of Post-Traumatic Stress Syndrome Causes Phenotype-Associated Morphological Changes and Hypofunction of the Adrenal Gland.

BACKGROUND: Rats exposed to chronic predator scent stress mimic the phenotype of complex post-traumatic stress disorder (PTSD) in humans, including altered adrenal morphology and function. High- and low-anxiety phenotypes have been described in rats exposed to predator scent stress (PSS). This study aimed to determine whether these high- and low-anxiety phenotypes correlate with changes in adrenal histomorphology and corticosteroid production. METHODS: Rats were exposed to PSS for ten days. Thirty days later, the rats' anxiety index (AI) was assessed with an elevated plus-maze test. Based on differences in AI, the rats were segregated into low- (AI ≤ 0.8, n = 9) and high- (AI > 0.8, n = 10) anxiety phenotypes. Plasma corticosterone (CORT) concentrations were measured by ELISA. Adrenal CORT, desoxyCORT, and 11-dehydroCORT were measured by high-performance liquid chromatography. After staining with hematoxylin and eosin, adrenal histomorphometric changes were evaluated by measuring the thickness of the functional zones of the adrenal cortex. RESULTS: Decreased plasma CORT concentrations, as well as decreased adrenal CORT, desoxyCORT and 11-dehydroCORT concentrations, were observed in high- but not in low-anxiety phenotypes. These decreases were associated with increases in AI. PSS led to a significant decrease in the thickness of the zona fasciculata and an increase in the thickness of the zona intermedia. The increase in the thickness of the zona intermedia was more pronounced in low-anxiety than in high-anxiety rats. A decrease in the adrenal capsule thickness was observed only in low-anxiety rats. The nucleus diameter of cells in the zona fasciculata of high-anxiety rats was significantly smaller than that of control or low-anxiety rats. CONCLUSION: Phenotype-associated changes in adrenal function and histomorphology were observed in a rat model of complex post-traumatic stress disorder.

The Age-Dependent Changes of the Human Adrenal Cortical Zones Are Not Congruent.

BACKGROUND: While previous studies indicate that the zonae reticularis (ZR) and glomerulosa (ZG) diminish with aging, little is known about age-related transformations of the zona fasciculata (ZF). OBJECTIVES: To investigate the morphological and functional changes of the adrenal cortex across adulthood, with emphasis on (i) the understudied ZF and (ii) sexual dimorphisms. METHODS: We used immunohistochemistry to evaluate the expression of aldosterone synthase (CYP11B2), visinin-like protein 1 (VSNL1), 3ß-hydroxysteroid dehydrogenase type II (HSD3B2), 11ß-hydroxylase (CYP11B1), and cytochrome b5 type A (CYB5A) in adrenal glands from 60 adults (30 men), aged 18 to 86. Additionally, we employed mass spectrometry to quantify the morning serum concentrations of cortisol, 11-deoxycortisol (11dF), 17α-hydroxyprogesterone, 11-deoxycorticosterone, corticosterone, and androstenedione in 149 pairs of age- and body mass index-matched men and women, age 21 to 95 years. RESULTS: The total cortical area was positively correlated with age (r = 0.34, P = 0.008). Both the total (VSNL1-positive) and functional ZG (CYP11B2-positive) areas declined with aging in men (r = -0.57 and -0.67, P < 0.01), but not in women. The CYB5A-positive area declined with age in both sexes (r = -0.76, P < 0.0001). In contrast, the estimated ZF area correlated positively with age in men (r = 0.59, P = 0.0006) and women (r = 0.49, P = 0.007), while CYP11B1-positive area remained unchanged across ages. Serum cortisol, corticosterone, and 11-deoxycorticosterone levels were stable across ages, while 11dF levels increased slightly with age (r = 0.16, P = 0.007). CONCLUSION: Unlike the ZG and ZR, the ZF and the total adrenal cortex areas enlarge with aging. An abrupt decline of the ZG occurs with age in men only, possibly contributing to sexual dimorphism in cardiovascular risk.

Thyroid Hormone Deficiency Suppresses Fetal Pituitary-Adrenal Function Near Term: Implications for the Control of Fetal Maturation and Parturition.

Background: The fetal hypothalamic-pituitary-adrenal (HPA) axis plays a key role in the control of parturition and maturation of organ systems in preparation for birth. In hypothyroid fetuses, gestational length may be prolonged and maturational processes delayed. The extent to which the effects of thyroid hormone deficiency in utero on the timing of fetal maturation and parturition are mediated by changes to the structure and function of the fetal HPA axis is unknown. Methods: In twin sheep pregnancies where one fetus was thyroidectomized and the other sham-operated, this study investigated the effect of hypothyroidism on circulating concentrations of adrenocorticotrophic hormone (ACTH) and cortisol, and the structure and secretory capacity of the anterior pituitary and adrenal glands. The relative population of pituitary corticotrophs and the masses of the adrenal zones were assessed by immunohistochemical and stereological techniques. Adrenal mRNA abundances of key steroidogenic enzymes and growth factors were examined by quantitative polymerase chain reaction. Results: Hypothyroidism in utero reduced plasma concentrations of ACTH and cortisol. In thyroid-deficient fetuses, the mass of corticotrophs in the anterior pituitary gland was unexpectedly increased, while the mass of the zona fasciculata and its proportion of the adrenal gland were decreased. These structural changes were associated with lower adrenocortical mRNA abundances of insulin-like growth factor (IGF)-I and its receptor, and key steroidogenic enzymes responsible for glucocorticoid synthesis. The relative mass of the adrenal medulla and its proportion of the adrenal gland were increased by thyroid hormone deficiency in utero, without any change in expression of phenylethanolamine N-methyltransferase or the IGF system. Conclusions: Thyroid hormones are important regulators of the structure and secretory capacity of the pituitary-adrenal axis before birth. In hypothyroid fetuses, low plasma cortisol may be due to impaired adrenocortical growth and steroidogenic enzyme expression, secondary to low circulating ACTH concentration. Greater corticotroph population in the anterior pituitary gland of the hypothyroid fetus indicates compensatory cell proliferation and that there may be abnormal corticotroph capacity for ACTH synthesis and/or impaired hypothalamic input. Suppression of the development of the fetal HPA axis by thyroid hormone deficiency may contribute to the delay in fetal maturation and delivery observed in hypothyroid offspring.

Atypical antipsychotic drug modulates early life infection induced impairment of hypothalamic-pituitary-adrenal axis: An age related study in mice.

Evidences from human and animal studies indicate that exposure to infection during early life act as a stressor to impair the hypothalamic-pituitary-adrenal (HPA) axis and may be one of the contributing factors of mental illness of later life. Several atypical antipsychotic drugs (AAPDs) proved to be effective in alleviating psychiatric illness through normalization of HPA axis. However, AAPD are least tried to evaluate their efficacy in modulation of HPA axis impaired under infection. The present study elucidated that the treatment with AAPD paliperidone (PAL: 0.025 mg/kg/bw and 0.05 mg/kg/bw) during periadolescence period (postnatal day 35- postnatal day 56) dose-dependently normalized the HPA axis of the female mice who were gestationally (gestational day 15 and 17) exposed to bacterial endotoxin lipopolysaccharide (LPS: 800 µg/kg/bw; intraperitoneally). The effectiveness of PAL treatment in counteracting the LPS induced hyperactivity of HPA axis was age-related, better observed at postnatal day 120 than at postnatal day 200. The PAL modulation of HPA axis reflected at different levels: inhibition of hypothalamic CRF expression and reduction in plasma levels of adrenocorticotropin and corticosterone. Histopathological alterations such as hypertrophy and/or hyperplasia in cortical zona fasciculata as well as medullary chromaffin cells of adrenal also normalized on PAL treatment. The comparatively long wash out period after drug treatment (postnatal day 57- postnatal day 200) along with age related hormonal imbalance could be correlated to less effectiveness of PAL on HPA axis at postnatal day 200. PAL modulation of HPA axis might be through maintenance of cytokines and reproductive axis homeostasis.

Enlargement of the human adrenal zona fasciculata and chronic psychiatric illness - an autopsy-based study.

Severe mental illness (SMI) is associated with a reduced life expectancy of up to 20 years. One possible contributor to this fact is dysregulation of the hypothalamus-pituitary-adrenal (HPA)-axis. Looking at the morphology of effector organs, such as the adrenal glands themselves, could reveal insights into organ function and response to possible HPA-dysregulation. This forensic autopsy-based study investigated if there were any morphological changes in adrenal glands between decedents who had previously been submitted to a psychiatric hospital with a diagnosis of schizophrenia (n = 34), bipolar (n = 5), or depressive disorder (n = 20), any other psychiatric diagnosis (n = 36) compared with decedents who had no previous psychiatric admission (n = 40). Length of admissions to psychiatric wards and admission in the 180 days preceding death was included in regression as proxy variables for severity of illness. On the macroscopic level, we found no difference in gland weight or volume. On the microscopic level, we found a 25% increase in cross-sectional area of the zona fasciculata (ZF) in decedents who had a diagnosis of schizophrenia compared with controls (p = 0.033). Other diagnosis groups did not differ from controls. Total admission length was positively correlated with area of the ZF.Lay SummaryPeople with a severe mental disorder may be in a constant state of increased stress, which is harmful. This study looked at the adrenal gland, which produces stress hormones, to see if they were different in deceased persons who had suffered from a severe mental illness. We found that the part of the adrenal gland that produces stress hormones is larger in deceased patients who suffered from schizophrenia, but not other types of psychiatric illnesses, compared to deceased persons with no history of psychiatric illness.

ANO4 (Anoctamin 4) Is a Novel Marker of Zona Glomerulosa That Regulates Stimulated Aldosterone Secretion.

Microarray comparison of the transcriptomes of human adrenal zona glomerulosa (ZG) and zona fasciculata found several ZG-specific genes that negatively regulate aldosterone secretion. The third and most significantly upregulated ZG-gene (19.9-fold compared with zona fasciculata, P=6.58×10-24) was ANO4, a putative Ca2+-activated chloride channel. We have investigated the role of ANO4 in human adrenal, and whether it functions like the prototype anoctamin, ANO1. We evaluated ANO4 mRNA and protein expression in human adrenal by qPCR and immunohistochemistry, compared the effects of ANO4 and ANO1 overexpression on baseline and stimulated aldosterone secretion and cell proliferation in H295R cells, and analyzed ANO4 activity as a Ca2+-activated chloride channel in comparison with other anoctamins by a fluorescence-based functional assay. The expression of ANO4 in ZG was confirmed by qPCR as 23.21-fold upregulated compared with zona fasciculata (n=18; P=4.93×10-7). Immunohistochemistry found cytoplasmic, ZG-selective expression of ANO4 (anoctamin 4) protein. ANO4 overexpression in H295R cells attenuated calcium-mediated aldosterone secretion and cell proliferation in comparison to controls. The latter effects were in a different direction to those of ANO1. The functional assay showed that, in contrast to ANO1, ANO4 expression results in low levels of calcium-dependent anion transport. In conclusion, ANO4 is one of the most highly expressed genes in ZG. It attenuates stimulated aldosterone secretion and cell proliferation. Although belonging to a family of Ca2+-activated chloride channels, it does not generate significant plasma membrane chloride channel activity.

Decrease in Lipid Droplets in Adrenal Cortex of Male Wistar Rats after Chronic Exposure to Energy Drinks.

Background and objectives: Energy drinks are popular non-alcoholic beverages. They are consumed in large amounts, mainly by active, young people. Although they are easily accessible and marketed as safe, numerous cases of adverse effects have been published, including cardiac arrest, arrythmias, acute hepatitis, and renal failure. The aim of the current study is the assessment of energy drink influence on the histological structure of adrenal cortex in rats. Material and Methods: 15 male young Wistar rats were equally divided into three groups: control (C), experimental (E) and reversibility control (RC). C group received water and standard rodent food ad libitum while both E and RC groups had additionally unlimited access to energy drinks. C and E groups were decapitated after 8 weeks and RC was given another 8 weeks without energy drinks. Adrenal glands were embedded in paraffin blocks and 5 µm slides were prepared and stained according to standard H&E and Masson's trichrome protocols. Additionally, immunohistochemical stainings against Ki-67, p53, CTGF and caspase-3 were prepared. Results: Decreased vacuolization and numerous pyknotic nuclei were noted in E and RC groups. Overexpression of caspase-3 was noted both subcapsular in zona glomerulosa and along sinusoids in zona fasciculata. Increased collagen deposition in zona glomerulosa and zona fasciculata of E and RC was observed. Insular and irregular overexpression of CTGF was noted. The overall picture of CTGF expression matched the Masson's trichrome. No significant difference was observed in Ki-67 expression. Conclusions: The results of the current study suggest that the stimulation is so intense that it causes significant damage to adrenal cortical cells, resulting in their apoptosis. It seems, however, that the observed effects are at least partially reversible.

Changes in Secretory Activity of Adrenal Zona Fasciculata Cells in Pubertal Rats Exposed to Low Doses of DDT in Different Periods of Ontogeny.

We studied secretory activity of adrenal zona fasciculata cells in pubertal rats exposed to low doses of endocrine disrupter DDT during prenatal and postnatal periods and only during postnatal period. In exposed animals, circulatory disturbances leading to degeneration and necrosis of cells as well as regeneration foci were revealed in the outer zona fasciculata. In rats exposed to DDT during the prenatal and postnatal periods, compensatory increase in secretory activity of cells due to increase in mitochondria content was noted in the inner zona fasciculata, which determined elevated serum concentration of corticosterone. In rats exposed to DDT only during the postnatal development, functional activity of zona fasciculata cells was suppressed, which attested to delayed upregulation of secretion.

Stress-induced changes in the aged-rat adrenal cortex. Histological and histomorphometric study.

BACKGROUND: Stress exposure exerts direct effects on the morphology and functionality of the adrenal cortex. In addition, ageing effects growth, differentiation, apoptosis and cellularity of the cortex. The missing data is the combined effect of stress and ageing on the adrenal cortex. The aim of this study was to demonstrate the structural changes in the adrenal cortex following the exposure to stress in the adult and aged albino rats. MATERIALS AND METHODS: Forty rats were divided into groups I and II (adult and senile). Each group was further subdivided into subgroups a and b (control and stressed). Light and electron microscopic studies were done. Area per cent of collagen fibres (Masson's trichrome-stained sections), number of proliferating cells (optical density immunoreactivity in the Ki67 stained sections) and thickness of the three adrenal zones were also measured. RESULTS: Lamellar separation of the capsule with subcapsular spindle cell hyperplasia and areas of ghost cells were observed in zona glomerulosa (ZG) and zona fasciculata (ZF) in group I-b. Separation and indentation of the capsule with its lamellar separation were observed in group II-a with the existence of multiple scattered degenerative foci in ZF and zona reticularis (ZR). Similar and aggressive was the architectural pattern of ZF in group II-b with the presence of areas of homogenous degeneration. The nuclei of ZG had marginated chromatin in group I-b and were pyknotic with deformed irregular outlines in group II-b. Multiple lysosomes and vacuolar degeneration mitochondria were also seen in group I-b. The nuclei of ZF were irregular with condensed marginated heterochromatin in group I-b, irregular with scattered chromatin in group II-a and indented with areas of chromatin destruction in group II-b. Mitochondria with disrupted cristae and cristolysis were also detected in group I-b. Numerous lipofuscin granules and dilated smooth endoplasmic reticulum were revealed in group II-b. The mean collagen fibre area per cent and the mean number of the proliferating cells in group II-b were significantly higher by 39% and 23%. The thickness of ZG decreased significantly by 20% in group I-b. Contrary, the thickness of both ZF and ZR increased significantly by 10% in group I-b. CONCLUSIONS: Histological alterations occurred in the adrenal cortex in response to stress, especially when coupled with the advance of age. This was accompanied by increase in the area per cent of collagen fibres and increase in the mean number of the proliferating cells in the adrenal cortex.

Histopathological and genetic characterization of aldosterone-producing adenomas with concurrent subclinical cortisol hypersecretion: a case series.

PURPOSE: Aldosterone-producing adenomas with concurrent subclinical cortisol hypersecretion are reported in an increasing number of patients. Five aldosterone-producing adenomas from patients with primary aldosteronism and subclinical hypercortisolism were examined. THE AIMS OF OUR STUDY WERE: (1) to analyze pathological features and immunohistochemical expression of CYP11B1 (11ß-hydroxylase) and CYP11B2 (aldosterone synthase) in these tumors; (2) to investigate somatic mutations involved in adrenal steroid hypersecretion and/or tumor growth. METHODS: Archival micro-dissected paraffin-embedded slides from tumor specimens were used for histological and molecular studies. Immunohistochemistry was performed using monoclonal anti-CYP11B1 and anti-CYP11B2 antibodies. Cellular composition was determined by examining for known features of zona fasciculata and zona glomerulosa, and immunoreactivity for CYP11B1 and CYP11B2 by McCarty H-score. Spot regions for mutations in KCNJ5, ATP1A1, ATP2B3, CACNA1D, PRKACA, and CTNNB1 gene sequences were evaluated. RESULTS: Four APAs showed a predominant (≥50%) zona fasciculata-like cell pattern: one tumor had CYP11B1 H-score = 150, no detectable CYP11B2 expression, and harbored a PRKACA p.Leu206Arg mutation (that we have reported previously elsewhere), one had no CYP11B1 expression, CYP11B2 H-score = 40, and no mutations; the remaining two adenomas had high CYP11B1 H-score (160 and 240, respectively) and low CYP11B2 H-score (30 and 15, respectively), with the latter harboring a CTNNB1 p.Ser45Phe activating mutation. One of five aldosterone-producing adenomas had a predominant zona glomerulosa-like pattern, CYP11B1 H-score = 15, CYP11B2 H-score = 180, and no mutations. CONCLUSIONS: The majority of aldosterone-producing adenomas with concurrent subclinical cortisol hypersecretion were composed mainly of zona fasciculata-like cells, while CYP11B1 and CYP11B2 immunostaining demonstrated clear heterogeneity. In a subset of cases, different somatic mutations may be involved in hormone excess and tumor formation.

Genetic and Histopathologic Intertumor Heterogeneity in Primary Aldosteronism.

Context: Whether primary aldosteronism (PA) is the consequence of a monoclonal or multiclonal process is unclear. Case Description: A 48-year-old man with severe bilateral PA refractory to medical therapy underwent unilateral adrenalectomy of the dominant adrenal. Although computed tomography showed three left-sided cortical nodules, postsurgical histopathology and genetic analysis revealed five different adrenocortical adenomas. Two zona fasciculata (ZF)-like aldosterone-producing adenomas (APAs) each harbored distinct known somatic KCNJ5 mutations (L168R and T158A). A zona glomerulosa-like APA harbored a known CACNA1D G403R somatic mutation, whereas a zona reticularis-like adenoma, which was grossly black in pigmentation with histologic characteristics more associated with cortisol-producing adenomas, expressed CYP11B2, CYP17, and DHEA-ST by immunohistochemistry (IHC) and harbored no known somatic mutations. The fifth adenoma was ZF-type, negative for CYP11B2 and CYP17 IHC, and harbored no known somatic mutations. Conclusions: This case highlights complex intertumor heterogeneity in histology, steroidogenesis, and somatic mutations in multiple adrenocortical adenomas arising in a single patient with PA. These findings suggest that the syndrome of PA can involve heterogeneous and multiclonal functional adrenal adenomas.

Microarray, qPCR, and KCNJ5 sequencing of aldosterone-producing adenomas reveal differences in genotype and phenotype between zona glomerulosa- and zona fasciculata-like tumors.

CONTEXT: Aldosterone-producing adenomas (APA) are heterogeneous. The recent finding of somatic KCNJ5 mutations suggests a genetic explanation. OBJECTIVES: The objectives of this study were the following: 1) to compare transcriptional profiles in APA and adjacent adrenal gland (AAG); 2) to test whether gene expression profile clusters with different cell histology; and 3) to measure the frequency of KCNJ5 mutations and determine the genotype-phenotype relationship. DESIGN/SETTING: The design of the study included laboratory analyses of 46 unselected APA. PATIENTS: The patients in this study had primary hyperaldosteronism with unilateral APA. INTERVENTIONS: The objectives of this study were the following: 1) Illumina beadchip analysis of RNA from eight paired APA-AAG; 2) a blinded review of cell histology for 46 APA; 3) laser capture microdissection of zona glomerulosa (ZG) and zona fasciculata (ZF) cells; and 4) sequencing of KCNJ5 in 46 APA. MAIN OUTCOME MEASURES: The main outcome measures of this study were the following: 1) a difference in gene expression profile and a correlation with histological markers of ZF; 2) a frequency of KCNJ5 mutations and phenotypic comparisons of wild type with mutant APA. RESULTS: The results of the study were the following: 1) a cluster analysis of microarray data separated APA from AAG. APA at opposite ends of the APA cluster had an approximately 800-fold difference in CYP17A1 mRNA expression, whereas histology showed 0% ZF-like cells in one vs. 100% in the other. A heat map ranking APA by CYP17A1 expression correctly predicted several genes (e.g. KCNK1, SLC24A3) to be enriched in laser capture microdissection samples of ZG; 2) known or novel mutations of KCNJ5 were found in 20 of 46 consecutive APA [43% (95% confidence interval [CI] (29, 58)%)]. The APA with KCNJ5 gene mutations were larger compared with tumors harboring the wild type, 1.63 [95% CI (1.37, 1.88)] vs. 1.14 [0.97, 1.30] cm (P = 0.0013), had predominantly ZF-like cells, and their CYP17A1 (log(2)-fold change) was higher than in wild type: -0.96 [95% CI (-0.07, -1.85)] vs. -2.54 [-1.61, -3.46], (P = 0.017). CONCLUSIONS: KCNJ5 mutations are common in APA, particularly those arising from ZF. The long-recognized heterogeneity among APA may have a genetic basis.

The acute effect of ethanol on adrenal cortex in female rats--possible role of nitric oxide.

AIMS: The present study was designed to investigate a possible role of endogenous nitric oxide (NO) in the adrenal response to an acute alcohol administration in female rats. To this end, N(ω)-nitro-L-arginine-methyl ester (L-NAME), a competitive inhibitor of all isoforms of NO synthase, was used. METHODS: Adult female Wistar rats showing diestrus Day 1 were treated with: (a) ethanol (2 or 4 g/kg, intraperitoneally); (b) L-NAME (30 or 50 mg/kg, subcutaneously) followed by either ethanol or saline 3 h later. Untreated and saline-injected rats were used as controls. The animals were killed 30 min after last injection. Adrenal cortex was analyzed morphometrically, and plasma levels of adrenocorticotropic hormone (ACTH) and serum concentrations of corticosterone were determined. RESULTS: Acute ethanol treatment enhanced the levels of ACTH and corticosterone in a dose-dependent manner. Stereological analysis revealed that acute alcohol administration induced a significant increase in absolute volume of the cortex and the zona fasciculata (ZF). In addition, ethanol at a dose of 4 g/kg increased volume density and length of the capillaries in the ZF. However, other stereological parameters were unaffected by alcohol exposure. Pretreatment with both doses of L-NAME had no effect on ethanol-induced changes. CONCLUSION: Obtained findings indicate that acute ethanol treatment stimulates the activity of the adrenal cortex and that this effect is not mediated by endogenous NO in female rats under these experimental conditions.

Chronic exposure to constant light affects morphology and secretion of adrenal zona fasciculata cells in female rats.

The effect of chronic exposure to light of adult Wistar rats on growth and function of adrenal zona glomerulosa (ZG) and zona fasciculata (ZF) were examined. The females were exposed to continuous light of 600 lux for 95 days, starting on day 30 of age. The controls were kept under a 12:12 h light-dark cycle, at ambient temperature. The rats were sacrificed by decapitation and the left adrenal gland of each animal was dissected out and prepared for morphometric analyses. In animals exposed to chronic lighting, the absolute and relative volume of ZG were insignificantly increased by 5% (p>0.05) compared to controls. The volume of ZG cells and their nuclei were insignificantly changed by 1% (p>0.05) in comparison with corresponding controls. The absolute and relative volume of ZF were significantly increased (by 14 and 9%, respectively; p<0.05), as compared to controls. The volume of ZF cells and their nuclei were significantly increased (by 12 and 9%, respectively; p<0.05). Serum concentration of corticosterone was also significantly (p<0.05) increased by 13% in light-exposed group in comparison with control rats. These findings suggest that continuous exposure of female rats to constant light increased growth and secretory activity of ZF cells.

Carbimazole-induced hypothyroidism causes the adrenal atrophy in 10 days' prenatally treated albino rats.

OBJECTIVE: To investigate the effects of carbimazole-induced hypothyroidism, and simultaneous administration of thyroxine (thyroid hormone analogue) on the adrenal glands of 10 days' prenatally treated albino rats. DESIGN: A comparative study. PLACE AND DURATION OF STUDY: Department of Anatomy, Basic Medical Sciences Institute (BMSI), Jinnah Postgraduate Medical Centre (JPMC), Karachi, from 15th July 2001 to 31st August 2001. PATIENTS AND METHODS: Ten days old albino rats of either gender, which were delivered by their respective mothers which were originally obtained from Charles River Breeding Laboratories, Brooklyn, Massachusetts, USA, and were cross bred, housed and maintained on the balanced diet in the Animal House of BMSI, JPMC, Karachi. Eighteen prenatally treated albino rats of 10 days old were used in the experiment and divided into three groups: X, Y and Z, comprising 06 animals in each group, i.e. from carbimazole treated mothers (X), carbimazole plus thyroxine treated mothers (Y), and controlled mothers (Z). At the end of 10th postnatal day all the animals were sacrificed, their adrenal glands were removed, fixed, sectioned, and stained with H&E. The adrenal histology with relation to its width of cortex, zones and number of cells in different zones of cortex were studied. RESULTS: Carbimazole-induced hypothyroidism causes the adrenal atrophy in the adrenals of 10 days' prenatally treated albino rats by decreasing the total width of cortex and its zones especially zona fasciculata. CONCLUSION: Carbimazole-induced hypothyroidism by carbimazole causes the shrinkage of adrenal cortex in 10 days prenatally treated albino rats.

Effect of acute heat stress on rat adrenal glands: a morphological and stereological study.

The morphological and stereological structure of rat adrenal gland was analysed by light microscopy after an acute (60 min) exposure to high ambient temperature (38 degrees C). A significant increase in plasma corticotrophin (ACTH) and serum corticosterone (CORT) concentrations was observed, confirming that acute heat exposure has a strong stressful effect. Under these conditions the adrenal gland mass and volume were decreased, probably as the consequence of adrenal cortex reduction, especially that of the zona fasciculata (ZF). Histological examination revealed that many ZF cells were deprived of lipid droplets. Fibrosis was observed in all parts of the adrenal gland, both cortex and medulla, of heat stressed animals. Mitotic figures were absent in cortical cells after heat exposure, but there were no differences in ZF and zona reticularis (ZR) small blood vessels compared to nonstressed controls.

Nature of changes in adrenocortical function in chronic hyperleptinemic female rats.

Neonatal treatment of rats with monosodium L-glutamate, which destroys hypothalamic arcuate nucleus neuronal bodies, induces several metabolic abnormalities; as a result, rats develop a phenotype of pseudoobesity. This study was designed to explore, in the monosodium L-glutamate-treated female rat, the influence of chronic hyperleptinemia on adrenal cortex functionality. For this purpose, we evaluated in control and hypothalamic-damaged rats: (a) in vivo and in vitro adrenocortical function, (b) adrenal leptin receptor immunodistribution and mRNA expression, and (c) whether the inhibitory effect of leptin on adrenal function remains. Our results indicate that, compared to normal counterparts, pseudoobese animals displayed (1) hyperadiposity, despite being hypophagic and of lower body weight, (2) in vivo and in vitro enhanced adrenocortical response to ACTH stimulation, (3) an in vitro adrenal fasciculata-reticularis cell hyper-sensitivity to ACTH stimulus, (4) hyperplasia of their adrenal zona fasciculata cells, and (5) adrenal fasciculata-reticularis cell refractoriness to the inhibitory effect of leptin on ACTH-stimulated glucocorticoid production due, at least in part, to decreased adrenal leptin receptor expression. These data further support that increased hypothalamo-pituitary-adrenal axis function, in the adult neurotoxin-lesioned female rat, is mainly dependent on the development of both hyperplasia of adrenal zona fasciculata and adrenal gland refractoriness to leptin inhibitory effect. Our study supports that adrenal leptin resistance could be responsible, at least in part, for enhanced glucocorticoid circulating levels in this phenotype of obesity.

Cellular characterization of the tropism of recombinant adenovirus for the adrenal glands.

BACKGROUND: Recombinant adenoviruses are widely used in gene therapy clinical trials. A particular tropism for the adrenal glands has been reported but the precise cellular base for this tropism has not been determined. MATERIALS AND METHODS: Recombinant adenoviruses were injected intravenously into Balb/c nu/nu or C57BL/6 mice. Seventy-two hours later, the animals were sacrificed and the adrenal glands and livers collected. The glands were sectioned and analyzed using immunohistochemical methods to detect adenoviral epitopes and transgene expression. Total RNA were extracted from the liver and adrenal glands of some animals and subjected to real-time RT-PCR. RESULTS: The only cell type infected in the adrenal glands of Balb/c nu/nu or C57BL/6 mice is the adrenocortical cells in the zona fasciculata. Quantitatively, the relative level of gene expression in the adrenal gland is comparable but lower than that measured in the liver. CONCLUSIONS: Systemic injection of recombinant adenovirus could be used as a procedure to restore adrenal steroidogenesis in clinical gene therapy protocols. In addition, our study suggest that adrenal dysfunction should be considered when criteria are established to assess the safety of gene therapy formulations administered systemically.

First case of feline spongiform encephalopathy in a captive cheetah born in France: PrP(sc) analysis in various tissues revealed unexpected targeting of kidney and adrenal gland.

Feline spongiform encephalopathy (FSE), affecting domestic and captive feline species, is a prion disease considered to be related to bovine spongiform encephalopathy. Here we report an immunohistological analysis of the first FSE-affected cheetah born in France. The duration of clinical signs, of which ataxia was the main one, was about 8 weeks. The distribution of abnormal prion protein (PrP(sc)) was studied by immunohistochemistry within 27 different tissues. Different antibodies were used to visualise abnormal PrP deposits in situ. PrP(sc )accumulation was detected in the central nervous system (cerebral cortex, cerebellum, brain stem, spinal cord, retina), in peripheral nerves and in lymphoid organs. PrP(sc) deposits were not observed within the enteric nervous system nor in several other organs, such as pancreas, ovary, liver and muscle. More interestingly, unusual PrP(sc )deposits were observed within the zona fasciculata/reticularis of the adrenal gland and within some glomeruli of the kidney raising the question of possible PrP(sc) excretion. The sympathetic innervation of these two organs was visualised and compared to the distribution of PrP(sc) deposits. Our results suggest the possibility that the infectious agent is spread by both haematogenous and nervous pathways.