S-Space College of Medicine/School of Medicine (의과대학/대학원) Dept. of Medicine (의학과) The Seoul Journal of Medicine The Seoul Journal of Medicine Vol. 29 No.3 (1988)
Effect of Osmolality on in vitro Basal and Angiotensin Ⅱ-Stimulated Aldosterone Secretion by Bovine Adrenal Glomerulosa Cells
Osmolality가 소부신 Glomerulosa Cells에서의 기저 및 Angiotension II 자극 알도스테론 분비에 미치는 영향
- Kim, Seong Yeon; Lee, Hong Kyu; Koh, Chang Soon; Min, Hun Ki
- Issue Date
- Seoul J Med, Vol.29 No.3, pp. 263-270
- We observed the effect of changes in Na concentration and the associated
changes in the osmolality of incubation media on aldosterone secretion by acutely dispersed
isolated bovine glomerulosa cells. We also examined whether this effect is due to changes in
Na concentration or to changes in osmolality.
When we increased Na concentration and osmolality by addition of NaCl, basal aldosterone
secretion was inversely related to the Na concentration and osmolality of the incubation
medium. However angiotensin II stimulation increased aldosterone secretion in Low and
Normal Na (130 and 149 mM) and osmolality (261 and 297 Osm) media more than in Lower
Na (103 mM) and osmolality (210 mOsm) medium.
In addition, when osmolality of the medium was increased by addition of NaCI, sucrose
and glucose, basal aldosterone secretion was inhibited to a similar extent and increment in
aldosterone above basal levels by angiotensin II stimulation was similar, whereas urea addition
had no effect.
From these results, we conclude that changes in Na concentration affect aldosterone
secretion by a mechanism sensitive to the osmolality rather than to the Na concentration.
Moreover, since increased osmolality of the incubation medium caused by urea addition has
no effect on basal aldosterone levels and increment in aldosterone above basal levels by
angiotensin II stimulation, changes in intracellular volume or composition appear to be an
important modulator of aldosterone secretion.