Altered corticosteroid metabolism differentially affects pituitary corticotropin response

1  Third Department of Internal Medicine, Gifu University School of Medicine, Gifu 500-8705; and 2  Gifu Prefectural Hospital, Gifu 500-8717, Japan To evaluate the effects of altered corticosteroid metabolism on the hypothalamic-pituitary-adrenal axis, we examined rats treated with glycyrrhizic acid...

Full description

Saved in:
Bibliographic Details
Published in:American journal of physiology: endocrinology and metabolism 2002-02, Vol.282 (2), p.E466-E473
Main Authors: Hanafusa, Junko, Mune, Tomoatsu, Tanahashi, Tetsuya, Isomura, Yukinori, Suwa, Tetsuya, Isaji, Mako, Daido, Hisashi, Morita, Hiroyuki, Murayama, Masanori, Yasuda, Keigo
Format: Article
Language:English
Subjects:
11-beta-Hydroxysteroid Dehydrogenases
Adrenal Cortex Hormones - metabolism
Adrenocorticotropic Hormone - blood
Adrenocorticotropic Hormone - metabolism
Animals
Corticosterone - blood
Corticotropin-Releasing Hormone - genetics
Corticotropin-Releasing Hormone - pharmacology
Glycyrrhizic Acid - pharmacology
Half-Life
Humans
Hydrocortisone - pharmacokinetics
Hydroxysteroid Dehydrogenases - genetics
Hypoglycemia - blood
Hypoglycemia - chemically induced
Hypothalamus - metabolism
Insulin
Male
Pituitary Gland - metabolism
Rats
Rats, Wistar
Receptors, Corticotropin-Releasing Hormone - genetics
Rifampin - pharmacology
RNA, Messenger - metabolism
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:1  Third Department of Internal Medicine, Gifu University School of Medicine, Gifu 500-8705; and 2  Gifu Prefectural Hospital, Gifu 500-8717, Japan To evaluate the effects of altered corticosteroid metabolism on the hypothalamic-pituitary-adrenal axis, we examined rats treated with glycyrrhizic acid (G rats) or rifampicin (R rats) for 7 days. The half-life of exogenously administered hydrocortisone as a substitute for corticosterone was longer in G rats and shorter in R rats, with no differences in basal plasma levels of ACTH or corticosterone. The ACTH responses to human corticotropin-releasing factor (CRF) or insulin-induced hypoglycemia were greater in G rats and tended to be smaller in R rats compared with those in the control rats, whereas the corticosterone response was similar. No difference was observed in the content and mRNA level of hypothalamic CRF among the groups. The number and mRNA level of CRF receptor and type 1 11 -hydroxysteroid dehydrogenase (11-HSD1) mRNA level in the pituitary were increased in G rats but not changed in R rats, suggesting that chronically increased intrapituitary corticosterone upregulates pituitary CRF receptor expression. In contrast, CRF mRNA levels in the pituitary were increased in R rats. Our data indicate novel mechanisms of corticosteroid metabolic modulation and the involvement of pituitary 11-HSD1 and CRF in glucocorticoid feedback physiology. corticotropin-releasing factor; corticotropin-releasing factor receptor; type 1 11 -hydroxysteroid dehydrogenase; glucocorticoid feedback
ISSN:0193-1849
1522-1555
DOI:10.1152/ajpendo.00065.2001