Effects of Fluoxetine on Membrane Potential and Ionic Currents in RINm5F Insulinoma Cells / 대한정신약물학회지
Korean Journal of Psychopharmacology
;
: 233-241, 2001.
Artículo
en Coreano
| WPRIM
| ID: wpr-153167
ABSTRACT
OBJECTIVE:
The purpose of this study was to investigate the effects of fluoxetine (Prozac) on membrane potential and ionic currents in RINm5F insulinoma cells.METHODS:
Membrane potential and ionic currents in RINm5F cell were recorded by using whole-cell and perforated-patch clamp techniques.RESULTS:
Under current clamp conditions, diazoxide (200 microM), an activator of K ATP channels, induced a hyperpolarization of the resting membrane potential (-16.1+/-1.4 mV, n=), which was accompanied by a abolition of action potential firing. This diazoxide-induced hyperpolarization was blocked by glibenclamide (10 microM). Fluoxetine produced significant depolarization of membrane potential (15.9+/-3.1 mV, n=) and blocked diazoxide-induced hyperpolarization. Diazoxide activated inward currents in the presence of high external K + (90 mM) at a holding potential of -60 mV. Fluoxetine suppressed diazoxide-activated currents in a concentration-dependent (IC 50 =.84 microM) manner. However, the inhibitory action of fluoxetine was not specific to K ATP currents because it also inhibited both voltage-activated K + and Ca 2+ currents in a concentration-dependent manner. K ATP currents were more sensitive to fluoxetine block than both voltage-activated K + and Ca 2+ currents.CONCLUSION:
Our results indicate that fluoxetine increased excitability of RINm5F cells mainly by the preferential block of K ATP currents. Fluoxetine-induced depolarization may influence insulin secretion in insulinoma cells.
Texto completo:
Disponible
Índice:
WPRIM (Pacífico Occidental)
Asunto principal:
Potenciales de Acción
/
Adenosina Trifosfato
/
Fluoxetina
/
Gliburida
/
Diazóxido
/
Incendios
/
Insulina
/
Insulinoma
/
Potenciales de la Membrana
/
Membranas
Idioma:
Coreano
Revista:
Korean Journal of Psychopharmacology
Año:
2001
Tipo del documento:
Artículo
Similares
MEDLINE
...
LILACS
LIS