RESUMO

Mitochondrial Ca(2+) and its relation with the contraction induced by phenylephrine was investigated. In normal Ca(2+), carbonyl cyanide p-(trifluoro-methoxy)phenyl-hydrazone (FCCP) and oligomycin produced contraction similar to that promoted by phenylephrine. Phenylephrine-induced contraction was reduced by FCCP+oligomycin. In Ca(2+)-free, FCCP+oligomycin did not induce contraction. Response to FCCP+oligomycin was reduced upon Ca(2+) repletion and this response was lower than that to phenylephrine. Ca(2+) concentration was increased by FCCP+oligomycin. Since a profuse net of sarcoplasmic reticulum encloses mitochondria, a cross-talk between the two organelles may play an important role in the phenylephrine-induced contraction in presence of Ca(2+) encountered in both sarcoplasmic reticulum and extracellular medium of anococcygeus cells.

Assuntos

Cálcio/metabolismo , Comunicação Celular/fisiologia , Mitocôndrias Musculares/metabolismo , Músculo Liso/metabolismo , Retículo Sarcoplasmático/metabolismo , Animais , Cafeína/farmacologia , Carbonil Cianeto p-Trifluormetoxifenil Hidrazona/farmacologia , Comunicação Celular/efeitos dos fármacos , Combinação de Medicamentos , Fura-2/análogos & derivados , Fura-2/metabolismo , Soluções Isotônicas , Masculino , Mitocôndrias Musculares/efeitos dos fármacos , Mitocôndrias Musculares/ultraestrutura , Contração Muscular/efeitos dos fármacos , Músculo Liso/citologia , Músculo Liso/efeitos dos fármacos , Oligomicinas/farmacologia , Fenilefrina/farmacologia , Potássio/farmacologia , Ratos , Ratos Wistar , Retículo Sarcoplasmático/efeitos dos fármacos , Retículo Sarcoplasmático/ultraestrutura , Desacopladores/farmacologia