2-Hydroxycarbazole induces Ca2+ release from sarcoplasmic reticulum by activating the ryanodine receptor.
Eur J Pharmacol
; 354(2-3): 245-51, 1998 Aug 07.
Article
em En
| MEDLINE
| ID: mdl-9754926
ABSTRACT
2-Hydroxycarbazole was shown to induce Ca2+ release from skeletal muscle and cardiac muscle sarcoplasmic reticulum at concentrations between 100-500 microM. This release was blocked by both 1 mM tetracaine and 30 microM ruthenium red which inhibit the ryanodine receptor or by pre-treatment with 10 mM caffeine which depletes the ryanodine receptor-containing Ca2+ stores. This, in addition to the fact that 2-hydroxycarbazole has little effect on Ca2+ ATPase activity, indicates that it activates Ca2+ release through the ryanodine receptor. The apparent EC50 value for release from both skeletal muscle and cardiac muscle sarcoplasmic reticulum was approximately 200 microM and maximal release occurred at 400-500 microM, making it approximately 20 times more potent than caffeine. The dose-dependency in the extent of Ca2+ release induced by 2-hydroxycarbazole was also apparently highly cooperative for both preparations. That 2-hydroxycarbazole was able to mobilize Ca2+ from non-muscle cell microsomes and in intact TM4 cells (which contain ryanodine receptors), makes this compound a more potent and commercially available alternative to caffeine in studying the role of this intracellular Ca2+ channel in a variety of systems.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Retículo Sarcoplasmático
/
Carbazóis
/
Cálcio
/
Canal de Liberação de Cálcio do Receptor de Rianodina
Limite:
Animals
Idioma:
En
Revista:
Eur J Pharmacol
Ano de publicação:
1998
Tipo de documento:
Article
País de afiliação:
Reino Unido