Study of Adrenocortical Function in Fever. Effect of high temperature on corticoidogenesis in isolated bovine adrenocortical cells.
- VernacularTitle:発熱時の副腎皮質機能に関する基礎的研究 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高温の影響
- Author:
Naoko KOSUGE
;
Ken-ichi KUBOYAMA
;
Noboru NAKAMICHI
- Publication Type:Journal Article
- Keywords:
Fever;
Adrenocortical function;
Corticoidogenesis
- From:The Journal of The Japanese Society of Balneology, Climatology and Physical Medicine
1996;59(2):93-98
- CountryJapan
- Language:Japanese
-
Abstract:
To study the adrenocortical function in fever, we examined the effect of high temperatures on the corticoidogenesis (CG) in isolated bovine adrenocortical cells. To evoke CG, a stimulus was given using adrenocorticotropic hormone (ACTH, 1pM to 10nM), which stimulates the receptor operated Ca2+ channel (ROC) and adenylate cyclase activity; dibutyryl cyclic AMP (db-cAMP, 1mM), which mimics intracellular action of cyclic AMP; and high (30mM) K+, which activates the voltage dependent Ca2+ channel (VDC). Cells were incubated for 1 hour with each of the above mentioned secretaogues at 37°C, 40°C, and 42°C (only for ACTH). Compared with incubation at 37°C, the log dose response curve of ACTH shifted to the right, the maximal effect decreased to about 60% at 40°C, and CG ceased at 42°C. The use of Ca2+ (1.2mM) alone evoked CG via the nonspecific Ca2+ channel (NSC) at 37°C, but not at 40°C. 30mM K+-induced CG decreased to below 50% at 40°C, but 1mM db-cAMP-induced CG decreased only to 80%. However, the conversion of 25-hydroxycholesterol to corticoid was not affected at 40°C
The results of these experiments show that VDC and NSC are not the main factors of CG at 40°C and that the enzyme activity beyond the side chain cleavage of cholesterol is not affected. Since the increases in cyclic AMP production and intracellular Ca2+ are essential in various stimulants-induced CGs, it is suggested that adenylate cyclase and ROC play a more important role in CG at 40°C than VDC and NSC.
