Adrenocortical Function during Hypothermia. (No.2). Inhibitory effect of low temperature on corticoidogenesis in isolated bovine adrenocortical cells.
- VernacularTitle:低体温法下の副腎皮質機能に関する基礎的研究 （第２報） ウシ副腎皮質遊離細胞におけるコルチコイド産生に対する低温の抑制効果
- Author:
Noboru NAKAMICHI
;
Ken-ichi KUBOYAMA
;
Naoko KOSUGE
;
Akiyoshi NIITSU
;
Takashi MATSUI
- Publication Type:Journal Article
- Keywords:
Hypothermia;
Adrenocortical function;
Corticoidogenesis
- From:The Journal of The Japanese Society of Balneology, Climatology and Physical Medicine
1995;58(3):147-152
- CountryJapan
- Language:Japanese
-
Abstract:
Effects of low temperature on corticoidogenesis (CG) were studied in isolated bovine adrenocortical cells. In the presence of Ca2+, cells were incubated with adrenocorticotropic hormone (ACTH) at 27°C and 37°C for 1 hour. After the incubation, the amount of corticoid was measured fluorometrically. After the incubation at 27°C, as compared with that at 37°C, the CGs induced by 10pM and 1nM ACTH decreased, but the CG induced by 10nM ACTH was not affected. Even in the absence of extracellular Ca2+, 10nM ACTH could induce the same degree of CGs at 37°C and 27°C, There was no difference in the amount of conversion of 25-hydroxycholesterol to corticoid between the incubations at 37°C and 27°C. The amount of conversion at 20°C, however, was significantly lower.
Our study shows that Ca2+ is not an important second messenger for CG at 27°C, and that the enzyme activity beyond side chain cleavage of cholesterol (SCC) does not diminish.
Because cyclic AMP and Ca2+ are known as second messengers of ACTH, it is suggested that cyclic AMP plays a more important role than Ca2+ in CG during hypothermia and that ACTH not only stimulates SCC but also activates enzyme (s) beyond SCC to evoke CG in the case of deep hypothermia.
