History of Adrenal Research: From Ancient Anatomy to Contemporary Molecular Biology.

The adrenal is a small, anatomically unimposing structure that escaped scientific notice until 1564 and whose existence was doubted by many until the 18th century. Adrenal functions were inferred from the adrenal insufficiency syndrome described by Addison and from the obesity and virilization that accompanied many adrenal malignancies, but early physiologists sometimes confused the roles of the cortex and medulla. Medullary epinephrine was the first hormone to be isolated (in 1901), and numerous cortical steroids were isolated between 1930 and 1949. The treatment of arthritis, Addison's disease, and congenital adrenal hyperplasia (CAH) with cortisone in the 1950s revolutionized clinical endocrinology and steroid research. Cases of CAH had been reported in the 19th century, but a defect in 21-hydroxylation in CAH was not identified until 1957. Other forms of CAH, including deficiencies of 3ß-hydroxysteroid dehydrogenase, 11ß-hydroxylase, and 17α-hydroxylase were defined hormonally in the 1960s. Cytochrome P450 enzymes were described in 1962-1964, and steroid 21-hydroxylation was the first biosynthetic activity associated with a P450. Understanding of the genetic and biochemical bases of these disorders advanced rapidly from 1984 to 2004. The cloning of genes for steroidogenic enzymes and related factors revealed many mutations causing known diseases and facilitated the discovery of new disorders. Genetics and cell biology have replaced steroid chemistry as the key disciplines for understanding and teaching steroidogenesis and its disorders.

The longevity gene mIndy (I'm Not Dead, Yet) affects blood pressure through sympathoadrenal mechanisms.

Reduced expression of the plasma membrane citrate transporter INDY (acronym I'm Not Dead, Yet) extends life span in lower organisms. Deletion of the mammalian Indy (mIndy) gene in rodents improves metabolism via mechanisms akin to caloric restriction, known to lower blood pressure (BP) by sympathoadrenal inhibition. We hypothesized that mIndy deletion attenuates sympathoadrenal support of BP. Continuous arterial BP and heart rate (HR) were reduced in mINDY-KO mice. Concomitantly, urinary catecholamine content was lower, and the decreases in BP and HR by mIndy deletion were attenuated after autonomic ganglionic blockade. Catecholamine biosynthesis pathways were reduced in mINDY-KO adrenals using unbiased microarray analysis. Citrate, the main mINDY substrate, increased catecholamine content in pheochromocytoma cells, while pharmacological inhibition of citrate uptake blunted the effect. Our data suggest that deletion of mIndy reduces sympathoadrenal support of BP and HR by attenuating catecholamine biosynthesis. Deletion of mIndy recapitulates beneficial cardiovascular and metabolic responses to caloric restriction, making it an attractive therapeutic target.

Anatomical investigation of the measurements, shape and arterial irrigation of the adrenal gland in New Zealand rabbits / Investigação anatômica das medidas, forma e irrigação arterial da glândula adrenal em coelhos da raça Nova Zelândia

Rabbits have been used as an experimental model in many studies. These studies are important not only for veterinary clinicians, but also for researchers in different fields. The aim of this research was to describe gross morphological measurement, shape and arterial supply of the adrenal glands in healthy New Zealand rabbits. Dissections were performed in 30 adult rabbits, 15 males and 15 females, without macroscopic adrenal pathology. Adrenal measurements were made with a digital caliper: length, width, and thickness. The origin of the adrenal arteries was also determined. Both adrenal glands were localized cranially to the respective kidneys. The mean of the right adrenal gland was 0.88 cm length, 0.42 cm width and 0.16 cm thickness; the left gland measured 0.72 cm, 0.46 cm, and 0.17 cm, respectively. The right gland was significantly more elongated than the left (p = 0.0003) and the means of the measurements did not differ between sexes. Most of the right adrenal glands had a piriform shape (73.3%), whereas most of the left gland exhibited a "bean-shaped" aspect (60.0%). The arterial supply was found to arise from different arteries: lumbar, aorta, renal, caudal mesenteric, and testicular or ovarian. Comparatively, the descriptions of shape, position and arterial irrigation of the adrenal gland in rabbits are similar to those available in rodents. The data from the present investigation will assist in the interpretation of pathological and / or experimental findings in New Zealand rabbits.

Coelhos têm sido utilizados como modelo experimental em muitos estudos. Esses estudos são importantes não apenas para médicos veterinários, mas também para pesquisadores de diferentes campos. O objetivo desta pesquisa foi descrever as medidas morfológicas macroscópicas, forma e suprimento arterial das glândulas adrenais em coelhos saudáveis da raça Nova Zelândia. As dissecções foram realizadas em 30 coelhos adultos, 15 machos e 15 fêmeas, sem sinais macroscópicos de patologia adrenal. As medidas adrenais foram realizadas com paquímetro digital: comprimento, largura e espessura. A origem das artérias adrenais também foi determinada. Ambas as glândulas adrenais foram localizadas cranialmente nos respectivos rins. A média da glândula adrenal direita foi de 0,88 cm de comprimento, 0,42 cm de largura e 0,16 cm de espessura; a glândula esquerda mediu 0,72 cm, 0,46 cm e 0,17 cm, respectivamente. A glândula direita foi significativamente mais alongada que a esquerda (p = 0,0003) e as médias das medidas não diferiram entre os sexos. A maioria das glândulas adrenais direitas tinha uma forma piriforme (73,3%), enquanto a maioria da glândula esquerda exibia um aspecto em "forma de feijão" (60,0%). Verificou-se que o suprimento arterial provém de diferentes artérias: lombar, aorta, renal, mesentérica caudal e testicular ou ovariana. Comparativamente, as descrições de forma, posição e irrigação arterial da glândula adrenal em coelhos são semelhantes às disponíveis em roedores. Os dados da presente investigação ajudarão na interpretação de achados patológicos e / ou experimentais em coelhos da raça Nova Zelândia.

Adrenal Incidentaloma.

An adrenal incidentaloma is now established as a common endocrine diagnosis that requires a multidisciplinary approach for effective management. The majority of patients can be reassured and discharged, but a personalized approach based upon image analysis, endocrine workup, and clinical symptoms and signs are required in every case. Adrenocortical carcinoma remains a real concern but is restricted to <2% of all cases. Functional adrenal incidentaloma lesions are commoner (but still probably <10% of total) and the greatest challenge remains the diagnosis and optimum management of autonomous cortisol secretion. Modern-day surgery has improved outcomes and novel radiological and urinary biomarkers will improve early detection and patient stratification in future years to come.

Adrenal glands uptake patterns in 18F-Fluoroethylcholine PET/CT. / Patrones de captación en las glándulas suprarrenales de la PET/TC con 18F-Fluoroetilcolina.

PURPOSE: To find reasons of different radioactive choline adrenal uptake in prostate or renal cancer patients who underwent 18F-fluoroethylcholine positron emission tomography/computed tomography. METHODS: Forty-nine positron emission tomography/computed tomography studies with radioactive choline (96 adrenal glands) were analysed with respect to the adrenal glands shape, uptake pattern and maximum standardised uptake value. Fifteen other parameters were recorded, assessed or counted, ratios of chosen parameters were calculated, and checked for correlation with adrenal glands uptake. RESULTS: Adrenal glands presented a wide range of radioactive choline uptake intensities (range 2-7.9) and different uptake patterns (diffuse, focal or mixed). Maximum uptake in the right (4.3±1.2) adrenal gland positively correlated with the thickness of the parenchyma at the point of maximal uptake (5.3mm±1.5) (p=0.000). Maximum uptake in the right and left adrenal gland, as well as mean adrenal gland uptake, correlated with maximum uptake in the pituitary gland (p=0.000, p=0.000 and p=0.001, respectively) and with maximum uptake in liver (p=0.008, p=0.000 and p=0.011, respectively). Neither hormonal treatment nor patients' age significantly correlated with standardised uptake values of adrenal glands in the studied group. CONCLUSIONS: The variability of radiocholine uptake in adrenal glands depends probably on overall body metabolism and hypophyseal function expressed by statistically significant correlation with liver and pituitary gland uptake. Predominant focal or mixed with focal areas uptake patterns on positron emission tomography in normal in computed tomography adrenal glands should be assessed with caution to avoid a diagnostic mistake.

CT characterisation of feline adrenal glands.

OBJECTIVES: The objectives of this study were to describe the CT characteristics of the adrenal glands in healthy cats, to provide normal reference biometry for adrenal gland size and attenuation values, and to investigate the association with age, sex, laterality and body weight. METHODS: Retrospective evaluation of 30 CT studies of healthy adult cats recruited from September 2013 to July 2015 was performed. Healthy cats >1 year of age were included based on the absence of clinical signs, unremarkable physical examination, normal results of the complete blood count, biochemical profile, feline immunodeficiency virus, feline leukaemia virus and Bartonella species infection tests. The relationship between gland biometry (size and attenuation values) and the age, sex, laterality and body weight of cats were tested by two-way ANOVA. The intraclass correlation coefficient was assessed and mean, SD, range and reference interval provided. RESULTS: Twenty-seven cats were included. Bilobed, arrowhead and oval adrenal gland shape patterns were recognised, the first being most common. No statistically significant differences were observed between the biometric parameters (length, height and attenuation values) and age, sex, laterality or body weight of the cats. Regarding the width of the adrenal glands, there was a statistically significant effect of sex and laterality. The length (11.6 ± 2.1 mm) and height (6.1 ± 1.3 mm) were the most consistent biometrical parameters to describe adrenal glands. CONCLUSIONS AND RELEVANCE: Adrenal gland shape, size and attenuation CT data of healthy feline patients are provided in this study, as well as normal reference intervals for morphometric characterisation based on adrenal length and height.

Contralateral adrenal width predicts the duration of prolonged post-surgical steroid replacement for subclinical Cushing syndrome.

OBJECTIVES: To identify pre-treatment factors affecting the duration of post-surgical steroid replacement in patients undergoing adrenalectomy for subclinical Cushing syndrome. METHODS: The present retrospective analysis included 64 patients who underwent unilateral laparoscopic adrenalectomy for subclinical Cushing syndrome. Adrenal tumor and contralateral adrenal sizes together with various clinical factors were studied in association with the duration of post-surgical steroid replacement. Adrenal tumor and contralateral adrenal size were measured at the level of the maximum transverse plane of the adrenal glands using computed tomography scan or magnetic resonance imaging. Cox's proportional hazards model was used for the statistical analysis. RESULTS: All 64 patients were treated with post-surgical steroid replacement after adrenalectomy. The median duration of the steroid treatment was 6 months. When assessing the duration of post-surgical steroid replacement, contralateral adrenal volume <0.745 cm3 , contralateral adrenal width <6.15 mm and serum cortisol after a 1-mg dexamethasone suppression test >2.65 µg/dL were significant predictors of prolonged post-surgical steroid treatment on univariate analysis. On multivariate analysis, contralateral adrenal width <6.15 mm was the only independent predictive factor for the prolonged post-surgical steroid replacement. CONCLUSIONS: Contralateral adrenal width seems to represent a significant predictive factor for the duration of post-surgical steroid replacement in subclinical Cushing syndrome patients. Pre-surgical assessment of image findings might help clinicians determine the total duration of steroid therapy after adrenalectomy.

Morphometric analysis of suprarenal glands (adrenal glands) with multislice computerized tomography / Análisis morfométrico de glándulas suprarenales (glándulas adrenales) con tomografía computarizada multicorte

The aim of our study are to determine the shape, vertebrae level, height, volume, corpus medial and lateral branch thicknesses of AG and the distance from some neighboring structures on multidetector computed tomography (MDCT) images and also to determine the relationship between these data and gender, age, height, weight and body mass index (BMI). The study was conducted on a total of 420 MDCT images consisted of 220 male (mean age 63.44±8.00, 50-81 years), 200 female (mean age 61.23±7.95, 50-84 years) healthy individuals. Vertebrae level of AG (VLAG), height of AG (HAG), adrenal gland volume (VAG), corpus thickness of AG (CTAG), medial section thickness of AG (MTAG) and lateral section thickness of AG (LTAG) were investigated. In our study, RAG were observed on T12 vertebrae level in 38.19 % of males and 42.5 % of females and LAG were also observed at that level in 39.55 % of the male and 51 % of the female individuals. RAG were observed in all males and 98.5 % of the females and LAG were observed 88.63 % of the males and 94 % of the females "Y" shaped. VAG were observed lower in males compared to females in age groups and VAG was observed increasing with age in males; decreased in 60-69 age group of females and increased again in 70 and plus age group. The aim of this study is to determine normal ranges of AG sizes and the relationship of each one with sex, age, height, weight and BMI.

Los objetivos de nuestro estudio fueron determinar la forma, el nivel vertebral, la altura, el volumen, el grosor de las ramas medial y lateral del cuerpo de glándulas suprarrenales (GSR) y la distancia de algunas estructuras vecinas en las imágenes de tomografía computada multidetector (TCMD) y determinar la relación entre estos datos y sexo, edad, estatura, peso e índice de masa corporal (IMC). El estudio se realizó en un total de 420 imágenes TCMD de 220 hombres (edad media 63,44 ± 8,00, 50-81 años) y 200 mujeres (edad media 61,23 ± 7,95, 50-84 años) todos sanos. Se investigó el nivel de la GSR respecto a las vértebras, la altura de GRS (AGSR), el volumen de la glándula suprarrenal (VGSR), el grosor del cuerpo, el espesor de la sección mediana de GSR (SMGSR) y el grosor de la sección lateral de GSR (SLGSR). En nuestro estudio, se observó la GSR derecha a nivel de vértebras T12 en el 38,19 % de los hombres y en el 42,5 % de las mujeres y la GSR izquierda se observó a ese nivel en el 39,55 % de los hombres y 51 % de las mujeres. La GSR se presentó en forma de «Y¼ en el lado derecho en todos los hombres y en el 98,5 % de las mujeres y en el lado izquierdo se observó en el 88,63 % de los hombres y 94 % de las mujeres. El VGSR era menor en los hombres en relación con las mujeres en los diferentes grupos de edad y aumentaba con la edad en los hombres; disminuyó en el grupo de 60-69 años de edad de las mujeres y aumentó nuevamente después de los 70 años.

Intrinsic factors, adrenal gland morphology, and disease burden in captive cheetahs (Acinonyx jubatus) in South Africa.

Adrenal gland weight (AW) and corticomedullary ratio (ACMR) are used as indicators of stress in animals. Captive cheetahs (Acinonyx jubatus) have higher ACMRs than free-ranging ones and stress has been linked to gastritis, amyloidosis, glomerulosclerosis, and myocardial fibrosis. We reviewed age, sex, body weight (BW), kidney weight (KW), and left AW and ACMR with necropsy findings in 51 South African captive cheetahs. Eleven common histopathologic lesions were counted for each animal as measure of its disease burden. Adrenal corticomedullary hyperplasia was significantly correlated with left AW and ACMR. Males had significantly higher AWs than females; other parameters showed no difference between the sexes. Disease burden, gastritis, and myocardial fibrosis were moderately correlated with adrenal morphology supporting prior evidence that gastritis and myocardial fibrosis are linked to stress. Glomerulosclerosis was not correlated with adrenal morphology and neither kidney nor liver amyloidosis contributed significantly to variation in AW or ACMR on multivariate analyses. Interstitial nephritis showed much stronger correlations with kidney and liver amyloidosis than gastritis. All three adrenal parameters were correlated with age; age was the only significant variable affecting ACMR on the multivariate analyses; and disease burden as well as systemic amyloidosis and kidney disease (except for fibrosis) showed moderate correlations with age. Age may, therefore, be important in the pathogenesis of disease in captive cheetahs, particularly of amyloidosis and kidney disease. None of the intrinsic measurements or adrenal parameters were sufficiently closely linked to disease to be used as ante-mortem proxies for disease burden or specific diseases. Zoo Biol. 36:40-49, 2017. © 2016 Wiley Periodicals, Inc.

Histology and histochemistry of the adrenal gland African giant rat (Cricetomys gambianus, Waterhouse) / Histología e histoquímica de la glándula adrenal de la rata africana gigante (Cricetomys gambianus, Waterhouse)

The histology and histochemistry of the adrenal gland of the African giant rat, AGR (Cricetomys gambianus Waterhouse) was carried out using ten adult male rats with the knowledge of providing information which could be helpful in an improved knowledge of the structure and function of the gland. The adrenal gland of the African giant rat has a distinct cortex and medulla surrounded by a thin rim of capsule. The adrenal cortex has three zones which are basically the zona glomerulosa, zona fasiculata and zona reticularis with the absence of zona intermedia. The zona glomerulosa contains polyhedral cells which form irregular clusters or cords while the zona fasiculata had radial cells of cuboidal or polyhedral shape. The cells of zona reticularis are similar to those of the zona fasiculata and in addition contain small cells as irregular cords and clusters. The cells of the adrenal medulla are composed of irregular epithelioid cells arranged in rounded groups or short cords and are mostly columnar or polyhedral chromaffin cells which are separated by sinusoids. The adrenal capsule, cortex and medulla were Periodic Acid-Schiff-positive.The adrenal capsule and adrenal medulla was Masson Trichrome-positive unlike the zona fasiculata and zona reticularis. The adrenal capsule and zona glomerulosa were Verhoeff-positive unlike the other zones of the gland. In conclusion the histology of the adrenal gland of the AGR is similar to those of other mammals with a few exceptions, the entire gland is rich in carbohydrate while the capsule and by extension, the outermost portion of the cortex are rich in collagen and elastic fibers. The outcome of this research provides information needed in the better improved understanding of the structure and function of the adrenal gland of the animal.

La histología y la histoquímica de la glándula suprarrenal de la rata africana gigante (Cricetomys gambianus Waterhouse) (RGA) se llevó a cabo utilizando diez ratas macho adultas con el objetivo de proporcionar información que podría ser útil para un mejor conocimiento de la estructura y función de la glándula. La glándula suprarrenal de la rata africana gigante tiene una corteza y una médula distintas, rodeadas por un borde delgado de la cápsula. La corteza suprarrenal tiene tres zonas que son básicamente: zona glomerulosa, zona fasciculata y zona reticular, con ausencia de zona intermedia. La zona glomerulosa contiene células poliédricas que forman racimos irregulares o cuerdas, mientras que la zona fasciculata tenía células radiales de forma cuboidal o poliédrica. Las células de la zona reticular son similares a las de la zona fasciculata y además contienen células pequeñas como cordones irregulares y racimos. Las células de la médula suprarrenal están compuestas por células epitelioides irregulares dispuestas en grupos redondeados o cuerdas cortas y son en su mayoría células cromafines columnares o poliédricas, que están separadas por sinusoides. La cápsula suprarrenal y la médula suprarrenal fueron positivas con tricrómico de Masson, a diferencia de la zona fasciculata y la zona reticular. La cápsula suprarrenal y la zona glomerulosa fueron positivas a Verhoeff, a diferencia de las otras zonas de la glándula. En conclusión, la histología de la glándula suprarrenal de la RGA es similar a la de otros mamíferos con algunas excepciones; toda la glándula es rica en carbohidratos, mientras que la cápsula y por extensión, la parte más externa de la corteza, son ricas en colágeno y fibras elásticas. El resultado de esta investigación proporciona información necesaria para mejorar la comprensión de la estructura y función de la glándula suprarrenal del animal.

Adrenal glands of Spix's yellow-toothed cavy (Galea spixii, Wagler, 1831): morphological and morphometric aspects / Glândulas adrenais de preás (Galea spixii, Wagler, 1831): aspectos morfológicos e morfométricos

Abstract Considering the physiological importance and need of greater morphophysiological knowledge of adrenal glands, the aims of present study were compare the morphometric data between left and right adrenal of male and female; perform a histological, scanning and transmission electron microscopy study showing tissue constitution of glands; finally, in order to define the presence and correct site of the cytochrome P450c17 expression in adrenal glands, immunohistochemical study of this enzyme was performed in 18 adrenal glands (right n=9 and left n=9) of nine adult Galea spixii (four males and five females). Right adrenal was more cranially positioned than left adrenal; dimensions (weight, length and width) of right adrenal was larger than left adrenal; no differences between male and female body and adrenal measurements were found; the morphology of cells and different amounts of lipid droplets may be related to the different demands of steroid hormones production, related to each zone of the adrenal cortex; and, the cytochrome P450c17 immunolocalization in fasciculate and reticular zone may be related with synthesis of 17-hydroxy-pregnenolone, 17-hydroxy-progesterone, dehydroepiandrosterone or androstenedione.

Resumo Considerando a importância fisiológica e a necessidade de melhor conhecimento morfofisiológico das glândulas adrenais, os objetivos do presente estudo foram comparar dados morfométricos entre adrenais direitas e esquerdas de machos e fêmeas; realizar estudos histológicos e microscopia eletrônica de varredura e transmissão revelando a constituição tecidual das glândulas; finalmente, foi realizado estudo imunohistoquímico com objetivo de definir a presença e correto sítio de expressão da citocromo P450c17 nas glândulas adrenais em 18 glândulas adrenais (direita n=9 e esquerda n=9) de nove Galea spixii adultos (quatro machos e cinco fêmeas). A glândula adrenal direita estava posicionada mais cranialmente que a adrenal esquerda; as dimensões (peso, comprimento e largura) da glândula adrenal direita foram maiores que as da esquerda; não houve diferença entre as medidas corpóreas e das adrenais entre machos e fêmeas; a morfologia das células e diferentes quantidades de gotículas lipídicas podem estar relacionadas a diferentes demandas na produção de hormônios esteroides relacionados a cada zona do córtex adrenal; e, a imunolocalização da citocromo P450 na zona fasciculada e reticular pode estar relacionado com a síntese de 17-hidroxi-pregnenolona, 17-hidroxi-progesterona, dehidroepiandrosterona ou androstenediona.

Adrenal clocks and the role of adrenal hormones in the regulation of circadian physiology.

The mammalian circadian timing system consists of a master pacemaker in the suprachiasmatic nucleus (SCN) and subordinate clocks that disseminate time information to various central and peripheral tissues. While the function of the SCN in circadian rhythm regulation has been extensively studied, we still have limited understanding of how peripheral tissue clock function contributes to the regulation of physiological processes. The adrenal gland plays a special role in this context as adrenal hormones show strong circadian secretion rhythms affecting downstream physiological processes. At the same time, they have been shown to affect clock gene expression in various other tissues, thus mediating systemic entrainment to external zeitgebers and promoting internal circadian alignment. In this review, we discuss the function of circadian clocks in the adrenal gland, how they are reset by the SCN and may further relay time-of-day information to other tissues. Focusing on glucocorticoids, we conclude by outlining the impact of adrenal rhythm disruption on neuropsychiatric, metabolic, immune, and malignant disorders.

Diethylstilbestrol decreased adrenal cholesterol and corticosterone in rats.

The synthetic oestrogen diethylstilbestrol (DES), which is known to bind oestrogen receptors (ERs), has been reported to have adverse effects on endocrine homeostasis; however, the molecular mechanisms underlying these effects are poorly understood. In this study, we treated rats with DES and found high levels of this compound in the liver, adrenal glands and pituitary gland, as compared with other tissues. We have also detected early adverse effects of DES in the adrenal glands. The adrenal glands of rats treated with DES (340 µg/kg body weight every 2 days) for 2 weeks showed increased weight and size and a decreased fat droplet size. Following 1 week of treatment with DES, the blood and adrenal corticosterone levels were substantially decreased without any histological alterations. The levels of the precursors for corticosteroid biosynthesis in the adrenal glands were also decreased, as determined using mass spectroscopy. Cholesterol, the principal material of corticosteroid biosynthesis, decreased substantially in the adrenal glands after only 1 week of treatment with DES. In conclusion, cholesterol insufficiency results in a reduction in adrenal corticosterone biosynthesis, which may lead to endocrine dysfunction, such as reproductive toxicity.

Gross anatomical studies on the adrenal gland in prenatal goat (Capra Hircus) / Estudio anatómico macroscópico de la glándula suprarrenal en fetos de cabra (Capra Hircus)

The present study was conducted on the 24 healthy and normal embryos/foeti of non- descript goat (Capra hircus) varying from day old to 150 days of gestation. The embryo/foeti were assigned into three groups according to their gestational ages; Groups I (0-50 days), II (51-100 days) and III (101-till term). At 38 days of gestation the primordia of right and left adrenal gland were observed as a pea shaped spherical swelling located just cranial to the respective metanephros. Biometrical studies revealed the increase in the all parameters of the adrenal gland with the advancement of age. Adrenal glands were harvested first grossly at 50 days of gestation.

El presente estudio se realizó en 24 embriones / fetos de cabra (Capra hircus) sanos de un día hasta los 150 días de gestación. Los embriónes fueron separados en tres grupos de acuerdo a la edad gestacional: grupos I (0-50 días), II (51 a 100 días) y III (101-till plazo). A los 38 días de gestación se observó el primordio de las glándulas suprarrenales derecha e izquierda como una protuberancia de forma esférica, situada justo en la zona craneal en relación al metanefros. C on el avance de la edad, estudios biométricos revelan aumento de todos los parámetros de la glándula suprarrenal. Las glándulas suprarrenales fueron extraídas inicialmente a los 50 días de gestación.

Ultrasonographical examination of feline adrenal glands: intra- and inter-observer variability.

Interpretation of ultrasonographical measurements requires an understanding of the source and the magnitude of variation. A substantial part of the variation can be attributed to the observer, the equipment or the animal. The aim of this study was to evaluate which adrenal gland measurement is the least variable within and between observers. Three experienced ultrasonographers examined six cats at three different times on the same day, more than 1 h apart, according to a strict scanning protocol. Seven ultrasonographical measurements were performed on each adrenal gland (maximal length on sagittal images, maximal height at the cranial and caudal poles on sagittal and transverse images, and maximal width of the cranial and caudal poles on transverse images). Height measurements in both planes showed the lowest variability within and between observers compared with length and width measurements. Descriptive ultrasonographical features, such as echogenicity of the gland, presence of hyperechoic spots or layering assessment, demonstrated satisfactory-to-good intra- and inter-observer agreement, whereas the shape assessment showed very poor inter-observer agreement. The results of this study describe a reliable scanning protocol that can be the basis for future adrenal ultrasonographical examinations for cats suspected of adrenal disease (eg, hyperaldosteronism, hyperadrenocorticism, sex hormone-producing tumours).

Assessment of the accuracy and reproducibility of adrenal volume measurements using MRI and its relationship with corticosteroid phenotype: a normal volunteer pilot study.

OBJECTIVE: The significant role of corticosteroids in hypertension and cardiovascular disease highlights the importance of the adrenal gland in these disorders. The ability to correlate corticosteroid production with adrenal volume offers a novel research tool and intermediate phenotype in cardiovascular disease. The aim of this study was to develop and validate the use of magnetic resonance imaging (MRI) in adrenal volume assessment and investigate whether this associates with corticosteroid production. DESIGN/METHODS: Twenty normotensive men underwent noncontrast 1·5T MRI scanning of adrenals, measurement of blood pressure and plasma corticosteroids. Left adrenal volume was calculated twice using standard segmentation software by four independent observers with differing levels of clinical expertise and segmentation experience. To optimize this process, adrenal 'phantoms' with known fixed volumes underwent MRI scanning and analysis by two observers. RESULTS: Intra-observer coefficients of repeatability (CoRs) in phantoms ranged from 0·23 to 0·43 ml (interobserver CoR 0·48 ml). In the subject group, mean adrenal volumes were 3·99-5·82 ml with intra-observer CoRs 0·27-1·94 ml. Interobserver variability was 2·73 ml. Segmentation expertise was the main factor affecting variability, with experienced observers having the lowest CoRs; clinical knowledge was a factor when combined with segmentation experience. Mean adrenal volume correlated with plasma glucocorticoids (r = 0·523, P < 0·05) and aldosterone (r = 0·515, P < 0·05) for the most experienced observer only. CONCLUSIONS: Measurement of adrenal volume using MRI is challenging; most accurate volumes are achieved using a single observer with both segmentation experience and anatomical knowledge. The data also provide novel preliminary evidence that adrenal gland volume may be associated with plasma corticosteroid concentrations supporting further study of adrenal volume and steroid production across a range of blood pressures.

Efectos de las experiencias adversas temprana y tardía en las características morfométricas y estereológicas de la glándula suprarrenal de ratas Sprague Dawley sometidas a estrés durante su vida adulta / Effects of early and late adverse experiences in morphometric and stereological characteristics of the adrenal gland of Sprague Dawley rats subjected to stress during adulthood

La ruptura temprana del vínculo materno y el aislamiento social son variables que están involucradas con los comportamientos social y emocional y también con el aumento de la ansiedad, especialmente en situaciones estresantes. Sin embargo, no se dispone de investigaciones que expliquen los cambios morfológicos de la glándula suprarrenal (GSR). Por lo anterior, el objetivo de este trabajo fue conocer experimentalmente, a través del modelo de alteración del vínculo social temprano madre-cría y alteración del vínculo social tardío por aislamiento, el efecto sobre las características morfométricas y estereológicas de la GSR, en ratas de la cepa Sprague Dawley sometidas a estrés crónico intermitente en la vida adulta. Utilizamos 35 ratas hembras recién nacidas, distribuidas en grupos de 7, en condiciones de lactancia y alimentación estandarizadas. Los grupos experimentales fueron expuestos a experiencias adversas temprana (E1), tardía (E2), temprana-tardía (E3) y posteriormente, sometidas a estrés crónico intermitente en la adultez. Se aisló la GSR izquierda de cada animal determinando características morfométricas y parámetros estereológicos. El peso absoluto fue mayor en los grupos control C2 y grupo experimental (E1). El número de células por mm3, el porcentaje de tejido glandular y la densidad de superficie en la zona fascicular de la GSR fue menor en el grupo E3. Las características estereológicas de la GRS en ratas, no sólo pueden ser afectadas por la exposición al estrés en la adultez, sino que también las experiencias adversas temprana y/o tardía juegan un rol importante en los cambios de los parámetros morfológicos cuantitativos observados en esta glándula.

The early break in maternal bonding and social isolation are variables involved with social and emotional behaviors and also with increased anxiety, especially in stressful situations. However, there is no research to explain the morphological changes of the adrenal gland (GSR). Therefore, our objective was to experimentally study through alteration model of social ties and early mother-cub bond alteration belated social isolation, the effect on the morphometric and stereological characteristics of the GSR in rats of the Sprague Dawley subjected to intermittent chronic stress in adulthood. We used 35 newborn female rats, divided into groups of 7 under lactating and standardized feeding conditions. The experimental groups were exposed to adverse experiences early (E1), late (E2), and early/late (E3) and subsequently, subject to intermittent chronic stress in adulthood. Left GSR was isolated from each animal determining morphometric characteristics and stereological parameters. The absolute weight was higher in control group C2 and the experimental group E1. In the group E3 number of cells per mm3, the percentage of glandular tissue and density of the surface in the fascicular area of the GSR was lower. Stereological characteristics of the GRS in rats, not only can be affected by exposure to stress in adulthood, but also early and / or late adverse experiences play an important role in the changes of quantitative morphological parameters observed in this gland.

Effect of prenatal stress on expression of glutathione system in neonatal rat brain.

AIM: Prenatal stress is known to adversely affect the fetal brain development and also neuronal loss. The mechanism(s) associated with prenatal stress induced developmental neurotoxicity remains obscure. Few studies point to the glutathione (GSH) antioxidant system which is an important molecular target for this toxicant. Hence the present study investigates the effect of prenatal stress on glutathione system in neonatal rat brain. MATERIAL AND METHODS: Three to four months old pregnant Wistar rats were subjected to restraint stress during early or late gestational period. The offspring were sacrificed on 40th day and their brain homogenate was subjected to antioxidant studies. The serum corticosterone and adrenal ascorbic acid levels were also estimated from offspring. RESULTS: The prenatal stress has resulted in an increase in the serum corticosterone and reduced adrenal ascorbic acid levels in neonatal pups. Prenatal stress during early or late gestation life showed reduced glutathione, glutathione reductase (GSSG-Rd) and superoxide dismutase (SOD) activity in offspring brain homogenate. CONCLUSION: These data suggest that stress during early or late gestation period affect glutathione system in developing neonatal rat brain, which is associated with elevated serum corticosterone and reduced adrenal ascorbic acid levels.

Sonography of the adrenal glands in the adult.

Although its capability has been overlooked, sonography can be a useful screening tool for adrenal lesion in adults. In this article, we discuss scan technique, patient positioning, and anatomic consideration for adrenal sonography in adults and illustrate sonographic appearance of normal adrenal gland as well as adrenal tumors and tumor-like lesions.