Elevated K(+) induces myristoylated alanine-rich C-kinase substrate phosphorylation and phospholipase D activation in glomerulosa cells.
Mol Cell Endocrinol
; 184(1-2): 65-76, 2001 Nov 26.
Article
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| MEDLINE
| ID: mdl-11694342
ABSTRACT
Elevated extracellular potassium concentrations ([K(+)](e)) are known to stimulate aldosterone secretion from adrenal glomerulosa cells in vivo and in vitro. The mechanism is thought to involve depolarization-elicited activation of voltage-dependent calcium channels and an increase in calcium influx. Until now protein kinase C (PKC) was thought not to play a role in the steroidogenic response to elevated [K(+)](e). In this report, we provide evidence in bovine adrenal glomerulosa cells to suggest that elevated [K(+)](e) increases PKC activity, as shown by an enhancement in the phosphorylation of myristoylated alanine-rich C-kinase substrate (MARCKS). Elevated [K(+)](e)-induced MARCKS phosphorylation was delayed and transient and was not the result of a local production of angiotensin II (AngII). MARCKS phosphorylation in response to elevated [K(+)](e) was not accompanied by phosphoinositide hydrolysis but was inhibited by a selective PKC inhibitor. Elevated [K(+)](e) also activated phospholipase D (PLD) in a delayed but sustained manner. We propose that the observed PLD activation mediates the elevated [K(+)](e)-induced MARCKS phosphorylation via PKC, although other factors may modulate this phosphorylation event.
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Base de datos:
MEDLINE
Asunto principal:
Fosfolipasa D
/
Fosfoproteínas
/
Potasio
/
Zona Glomerular
/
Péptidos y Proteínas de Señalización Intracelular
/
Proteínas de la Membrana
Límite:
Animals
Idioma:
En
Revista:
Mol Cell Endocrinol
Año:
2001
Tipo del documento:
Article
País de afiliación:
Estados Unidos