QT Interval Instability and Variability in Dogs with Hyperadrenocorticism

Abstract Hyperadrenocorticism is one of the most common endocrine diseases in dogs. In humans, it is clearly associated with a higher risk of cardiovascular events, but studies in dogs are scarce. To investigate the arrhythmogenic risk of dogs with hyperadrenocorticism, indices of variability and instability of the QT interval were studied in 38 dogs with hyperadrenocorticism and in 12 healthy dogs: variance (QTv), total instability (TI), short-term (STI) and long-term (LTI), and mean (QTm). Except for QTm, all parameters studied were higher in the hyperadrenocorticism group than in the control group. In addition, STI and QTv showed moderate positive correlation with left ventricle wall thickness. To a better understanding on the effect of the hypothalamus-pituitary-adrenal axis on ventricular repolarization, the hyperadrenocorticism group was subdivided according to the percentage of variation in plasma cortisol concentration (<30.1%; 30.1-60%; >60%) 8 hours after low-dose administration of dexamethasone. There was statistical difference in QTv, TI and LTI indices between the control group and the <30.1% and >60% groups, and in STI index between the control group and the >60% group. There was no statistical difference between sex groups in any of the electrocardiographic parameters studied. This result may indicate that the etiology of hyperadrenocorticism, and its consequent influence on hypothalamus-pituitary-adrenal axis could interfere on the heterogeneity of ventricular repolarization parameters in different ways, especially in the short-term stability; however further studies are necessary to understand the role of cortisol on electrical instability in dogs.

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Acupuncture blocks cold stress-induced increases in the hypothalamus–pituitary–adrenal axis in the rat

Journal of Endocrinology ◽

10.1530/joe-12-0404 ◽

2013 ◽

Vol 217 (1) ◽

pp. 95-104 ◽

Cited By ~ 39

Author(s):

Ladan Eshkevari ◽

Eva Permaul ◽

Susan E Mulroney

Keyword(s):

Cold Stress ◽

Chronic Stress ◽

Stress Hormones ◽

Control Group ◽

Adrenal Axis ◽

Significant Difference ◽

Hypothalamus Pituitary Adrenal Axis ◽

The Brain ◽

Treatment Control Group ◽

Pituitary Adrenal Axis

Electroacupuncture (EA) is used to treat chronic stress; however, its mechanism(s) of action in allaying stress remains unclear. The interplay of stress hormones of the hypothalamus–pituitary–adrenal axis (HPA) and the sympathetic nervous system (SNS) is critical in the stress response. Our objective was to determine whether EA at acupoint, stomach 36 (EA St36) is effective in preventing chronic cold stress-induced increased hormone levels in the rat by examining four groups of animals, three of which were exposed to cold and one of which was a non-treatment control group. Before exposure to the cold, two groups were treated with either EA St36, or Sham-EA, before 10 days of cold stress. The EA St36 animals demonstrated a significant decrease in peripheral HP hormones (ACTH and CORT) compared with stress animals (P<0.05). These effects were specific; rats receiving Sham-EA had elevation of these hormones, similar to the stress-only animals. These effects were mirrored centrally in the brain; CRH levels were significantly (P<0.05) reduced in EA St36 animals compared with the other animals. Finally, EA effect on peripheral and adrenal SNS hormones (norepinephrine (NE) and neuropeptide Y (NPY) respectively) was examined, with no significant difference noted in adrenal tyrosine hydroxylase or circulating NE in any of the groups. However, EA St36 was effective in preventing stress-induced elevation is adrenal Npy mRNA. These results indicate that EA St36 blocks the chronic stress-induced elevations in the HPA and the sympathetic NPY pathway, which may be a mechanism for its specific stress-allaying effects.

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Fetal Hypothalamus-Pituitary-Adrenal Responses to Estradiol Sulfate

Endocrinology ◽

10.1210/en.2011-0284 ◽

2011 ◽

Vol 152 (12) ◽

pp. 4966-4973 ◽

Cited By ~ 4

Author(s):

Charles E. Wood

Keyword(s):

Fetal Brain ◽

Control Group ◽

Cortisol Secretion ◽

Acth Secretion ◽

Fetal Sheep ◽

Adrenal Axis ◽

Arterial Blood ◽

Hypothalamus Pituitary Adrenal Axis ◽

Near Term ◽

Pituitary Adrenal Axis

Estradiol (E2) is an important modifier of the activity of the fetal hypothalamus-pituitary-adrenal axis. We have reported that estradiol-3-sulfate (E2SO4) circulates in fetal blood in far higher concentrations than E2 and that the fetal brain expresses steroid sulfatase, required for local deconjugation of E2SO4. We performed the present study to test the hypothesis that chronic infusion of E2SO4 chronically increases ACTH and cortisol secretion and that it shortens gestation. Chronically catheterized fetal sheep were treated with E2SO4 intracerebroventricular (n = 5), E2SO4 iv (n = 4), or no steroid infusion (control group, n = 5). Fetuses were subjected to arterial blood sampling every other day until spontaneous birth for plasma hormone analysis. Treatment with E2SO4 attenuated preparturient increases in ACTH secretion near term without affecting the ontogenetic rise in plasma cortisol. Infusion of E2SO4 intracerebroventricularly significantly increased plasma E2, plasma E2SO4, and plasma progesterone and shortened gestation compared with all other groups. These results are consistent with the conclusion that E2SO4: 1) interacts with the hypothalamus-pituitary-adrenal axis primarily by stimulating cortisol secretion and inhibiting ACTH and pro-ACTH secretion by negative feedback; and 2) stimulates the secretion of E2 and E2SO4. We conclude that the endocrine response to E2SO4 in the fetus is not identical with the response to E2.

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Recovery of the hypothalamus-pituitary-adrenal axis after short term high dose corticosteroid treatment in neurosurgical practice

Acta Neurochirurgica ◽

10.1007/bf01400849 ◽

1984 ◽

Vol 73 (3-4) ◽

pp. 157-163 ◽

Cited By ~ 4

Author(s):

P. Hedner ◽

G. Kullberg ◽

I. Bostedt

Keyword(s):

Corticosteroid Treatment ◽

High Dose ◽

Short Term ◽

High Dose Corticosteroid ◽

Adrenal Axis ◽

Hypothalamus Pituitary Adrenal Axis ◽

Dose Corticosteroid ◽

Pituitary Adrenal Axis

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Filtered air intervention reduces inflammation and hypothalamus–pituitary–adrenal axis activation in adult male and female rats after PM 2.5 exposure

Environmental Science and Pollution Research ◽

10.1007/s11356-020-09564-9 ◽

2020 ◽

Vol 27 (28) ◽

pp. 35341-35348

Author(s):

Cuiying Liu ◽

Jian Yang ◽

Longfei Guan ◽

Yuequan Zhu ◽

Xiaokun Geng

Keyword(s):

Adult Male ◽

Female Rats ◽

Male And Female ◽

Pm 2.5 ◽

Adrenal Axis ◽

Male And Female Rats ◽

Hypothalamus Pituitary Adrenal Axis ◽

Pituitary Adrenal Axis

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Deciphering the Association Between Hypothalamus‐Pituitary‐Adrenal Axis Activity and Obesity: A Meta‐Analysis

Obesity ◽

10.1002/oby.23125 ◽

2021 ◽

Author(s):

Giada Ostinelli ◽

Anaïs Scovronec ◽

Sylvain Iceta ◽

Anne‐Sophie Ouellette ◽

Simone Lemieux ◽

...

Keyword(s):

Meta Analysis ◽

Adrenal Axis ◽

Hypothalamus Pituitary Adrenal Axis ◽

Pituitary Adrenal Axis

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Contribution of Growth Arrest-Specific 5/miR-674 to the Hypothalamus Pituitary Adrenal Axis Regulation Effect by Electroacupuncture following Trauma

NeuroImmunoModulation ◽

10.1159/000513385 ◽

2021 ◽

pp. 1-13

Author(s):

Jing Zhu ◽

Chunxia Guo ◽

Pingping Lu ◽

Shuijin Shao ◽

Bing Tu

Keyword(s):

Hpa Axis ◽

Interleukin 1 ◽

Growth Arrest ◽

Luciferase Assay ◽

Function Evaluation ◽

Protein Levels ◽

Adrenal Axis ◽

Post Surgery ◽

Hypothalamus Pituitary Adrenal Axis ◽

Pituitary Adrenal Axis

Background: Electroacupuncture (EA) can improve trauma-induced hypothalamus pituitary adrenal axis (HPA) hyperactivity. However, the mechanism underlying the EA effect has not been fully understood. Methods and Study Design: This study was undertaken to explore the role of hypothalamic growth arrest-specific 5 (Gas5) in the regulation of EA on HPA axis function post-surgery. Paraventricular nuclear Gas5 levels were upregulated in rats using an intracerebroventricular injection of pAAV-Gas5. Primary hypothalamic neurons and 293T cells were cultured for miRNA and siRNAs detection. Radioimmunoassay, PCR, Western blot, and immunohistochemistry were used for HPA axis function evaluation. Results: The overexpression of Gas5 abolished the effect of EA on the regulation of trauma-induced HPA axis hyperactivity. Using a bioinformatics analysis and dual luciferase assay, we determined that miRNA-674 was a target of Gas5. Additionally, miRNA-674 levels were found to have decreased in trauma rats, and this effect was reversed after EA intervention. TargetScan analysis showed that serum and glucocorticoid inducible kinase 1 (SGK1) were targets of miR-674. Moreover, we found that SGK1 protein levels increased in trauma rats and SGK1 expression inhibition alleviated HPA axis abnormality post-surgery. EA could improve the number of hypothalamus iba-1 positive cells and hypothalamic interleukin 1 beta protein expression. Conclusions: Our study demonstrated the involvement of the hypothalamic Gas5/miRNA-674/SGK1 signaling pathway in EA regulation of HPA axis function after trauma.

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