Lithium-induced inhibition of Na-K ATPase and Ca ATPase activities in rat brain synaptosome
Journal of Korean Medical Science
;
: 7-13, 1995.
Artigo
em Inglês
| WPRIM
| ID: wpr-218195
ABSTRACT
To explore the action mechanism of lithium in the brain, the author investigated the effects of lithium on Na-K ATPase and Ca ATPase in rat brain synaptosomes prepared from forebrains by the method of Booth and Clark. The activities of Na-K ATPase and Ca ATPase were assayed by the level of inorganic phosphate liberated from the hydrolysis of ATP. Lithium at the optimum therapeutic concentration of 1 mM decreased the activity of Na-K ATPase from the control value of 19.08 +/- 0.29 to 18.27 +/- 0.10 micromoles Pi/mg protein/h and also reduced the activity of Ca ATPase from 6.38 +/- 0.12 to 5.64 +/- 0.12 micromoles Pi/mg protein/h. The decreased activity of Na-K ATPase will decrease the rate of Ca2+ efflux, probably via an Na-Ca exchange mechanism and will increase the rate of Ca2+ entry by the depolarization of nerve terminals. The reduced activity of Ca ATPase will result in the decreased efflux of Ca2+. As a Conclusion, it can be speculated that lithium elevates the intrasynaptosomal Ca2+ concentration via inhibition of the activities of Na-K ATPase and Ca ATPase, and this increased [Ca2+]i will cause the release of neurotransmitters and neurological effects of lithium.
Texto completo:
DisponíveL
Índice:
WPRIM (Pacífico Ocidental)
Assunto principal:
Sinaptossomos
/
Encéfalo
/
Ratos Sprague-Dawley
/
ATPases Transportadoras de Cálcio
/
ATPase Trocadora de Sódio-Potássio
/
Lítio
/
Animais
Limite:
Animais
Idioma:
Inglês
Revista:
Journal of Korean Medical Science
Ano de publicação:
1995
Tipo de documento:
Artigo
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