The adrenal cortex during activity and hibernation in the male little brown bat, Myotis lucifugus lucifugus: Annual rhythm of plasma cortisol levels

1981 ◽  
Vol 44 (3) ◽  
pp. 269-278 ◽  
Author(s):  
A.W. Gustafson ◽  
W.D. Belt
1976 ◽  
Vol 69 (3) ◽  
pp. 433-444 ◽  
Author(s):  
A. P. F. FLINT ◽  
ANNE B. M. ANDERSON ◽  
JANE D. GOODSON ◽  
PENELOPE A. STEELE ◽  
A. C. TURNBULL

SUMMARY Progesterone, 17α,20α-dihydroxypregn-4-en-3-one, androstenedione, total unconjugated oestrogen and oestrone sulphate have been measured by radioimmunoassays in maternal utero-ovarian venous, maternal peripheral venous and/or foetal posterior vena caval plasma from six sheep bearing bilaterally adrenalectomized lambs, in which premature parturition was induced by administration of glucocorticoid. Three of the ewes were ovariectomized, and in one of these three animals the foetal testes were also excised, at the time of foetal adrenalectomy. Adrenalectomy was judged to be complete on the basis of plasma cortisol levels in the neonatal lambs, and by examination of the site of ablation at necropsy. In all cases foetal administration of glucocorticoid led to the onset of labour, and lambing, and in all animals the hormonal changes preceding parturition were indistinguishable (either qualitatively or quantitatively) from the changes observed in animals carrying intact lambs. Since therapy with glucocorticoid alone successfully compensates for ablation of the foetal adrenal cortex, it is suggested that glucocorticoid is the only adrenal product required to cause parturition, and that foetal adrenal secretion of androgens may be unnecessary.


2021 ◽  
Vol 11 ◽  
Author(s):  
Yanfei Mao ◽  
Bo Xu ◽  
Wenbin Guan ◽  
Dunfeng Xu ◽  
Feng Li ◽  
...  

BackgroundThe majority of the critically ill patients may have critical illness-related corticosteroid insufficiency (CIRCI). The therapeutic effect of dexamethasone may be related to its ability to improve cortical function. Recent study showed that dexamethasone can reduce COVID-19 deaths by up to one third in critically ill patients. The aim of this article is to investigate whether SARS-CoV-2 can attack the adrenal cortex to aggravate the relative adrenal insufficiency.MethodsWe summarized the clinical features of COVID-19 reported in currently available observational studies. ACE2 and TMPRSS2 expression was examined in human adrenal glands by immunohistochemical staining. We retrospectively analyzed serum cortisol levels in critically ill patients with or without COVID-19.ResultsHigh percentage of critically ill patients with SARS-COV-2 infection in the study were treated with vasopressors. ACE2 receptor and TMPRSS2 serine protease were colocalized in adrenocortical cells in zona fasciculata and zona reticularis. We collected plasma cortisol concentrations in nine critically ill patients with COVID-19. The cortisol levels of critically ill patients with COVID-19 were lower than those in non-COVID-19 critically ill group. Six of the nine COVID-19 critically ill patients had random plasma cortisol concentrations below 10 µg/dl, which met the criteria for the diagnosis of CIRCI.ConclusionWe demonstrate that ACE2 and TMPRSS2 are colocalized in adrenocortical cells, and that the cortisol levels are lower in critically ill patients with COVID-19 as compared to those of non-COVID-19 critically ill patients. Based on our findings, we recommend measuring plasma cortisol level to guide hormonal therapy.


2017 ◽  
Vol 88 (10) ◽  
pp. 1629-1635 ◽  
Author(s):  
Ayaka Ono ◽  
Akihiro Matsuura ◽  
Yumi Yamazaki ◽  
Wakako Sakai ◽  
Kentaro Watanabe ◽  
...  

2021 ◽  
Vol 92 (1) ◽  
Author(s):  
Masato Aoyama ◽  
Minami Shioya ◽  
Yume Tsukamoto ◽  
Hitomi Hasegawa ◽  
Shoei Sugita

Behaviour ◽  
2014 ◽  
Vol 152 (1) ◽  
pp. 83-105 ◽  
Author(s):  
Quinn M.R. Webber ◽  
Liam P. McGuire ◽  
Steven B. Smith ◽  
Craig K.R. Willis

The influence of behaviour on host-parasite dynamics has theoretical support but few empirical studies have examined this influence for wild-captured hosts, especially in colonial species, which are thought to face generally high risk of exposure. Behavioural tendencies of hosts in novel environments could mediate host exposure. We tested the hypothesis that behavioural tendencies of hosts, and host sex and age, correlate with prevalence and intensity of ectoparasites in a gregarious mammal, the little brown bat (Myotis lucifugus). We also tested whether relationships between host behaviour and parasite prevalence and intensity would vary between taxa of ectoparasites which differ in host-seeking behaviour. We predicted that individual hosts displaying active and explorative behaviours would have higher prevalence and intensity of parasites that depend on physical contact among hosts for transmission (mites) but that host behaviour would not influence prevalence and intensity of mobile ectoparasites with active host-seeking behaviour (fleas). We recorded behavioural responses of wild-captured bats in a novel-environment test and then sampled each individual for ectoparasites. After accounting for age and sex we found mixed support for our hypotheses in some but not all demographics. More active adult and young of the year (YOY) males were more likely to host mites while more active adult and YOY females were less likely to host fleas. Our results highlight possible differences in the influence of host and parasite behaviour on parasite transmission dynamics for colonial compared to non-colonial species and have conservation implications for understanding pathogen transmission in bat white-nose syndrome and other wildlife diseases.


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