Inhibitory Effect of Low Temperature on Adrenocortical Corticoidogenesis. Investigations using primary cultured bovine adrenocortical cells.
- VernacularTitle:低温が副腎皮質コルチコイド産生に及ぼす抑制的影響 ウシ副腎皮質初代培養細胞を用いた検討
- Author:
Naoko KOSUGE
;
Noboru NAKAMICHI
- Publication Type:Journal Article
- Keywords:
Low temperature;
Corticoidogenesis;
Ca2+ channel blocker
- From:The Journal of The Japanese Society of Balneology, Climatology and Physical Medicine
1996;59(4):209-217
- CountryJapan
- Language:Japanese
-
Abstract:
To explore the adrenocortical function at low temperatures, the time-dependent transition of corticoidogenesis (CG) as well as the effect of verapamil, a Ca2+ channel blocker, on CG were examined at 27°C using primary cultured bovine adrenocortical cells.
CG was induced using adrenocorticotropic hormone (ACTH, 10pM to 1μM), which stimulates the receptor-operated Ca2+ channel and adenylate cyclase activity; dibutyryl cyclic AMP (db-cAMP, 0.25 to 4mM), which mimics the intracellular action of cyclic AMP; and 30mM K+, which activates the voltage-dependent Ca2+ channel. Cells were incubated together with each of these secretaogues for 3 hours at 27°C.
Though the CG induced by 1nM ACTH-and 1mM db-cAMP increased for 3 hours at 27°C in the presence of 1.2mM Ca2+, the CG induced by 30mM K+ did not show any increase after 2 hours.
Both 5μM and 10μM of verapamil inhibited the CG induced by 10pM ACTH dose-dependently at 37°C. However, 5μM of verapamil showed no inhibiting effect at 27°C. Even 10μM verapamil did not influence the CG induced by 1mM db-cAMP.
In the absence of extracellular Ca2+, 10μM verapamil did not influence the CG induced by ACTH (10nM to 1μM) or db-cAMP (0.25 to 4mM) at 27°C.
These experiment results show that the functions of adrenocortical cells are kept effective for 3 hours and that Ca2+ is also important for CG at 27°C. Although it is well known that the increases in both cyclic AMP and intracellular Ca2+ are essential for the CG induced by various stimulants at 37°C, it is suggested that cyclic AMP plays a more important roll in CG than Ca2+ does at low temperatures.
