[Effect of 8-(N,N'-diethylamino)-n-octyl-3,4,5-trimethoxybenzoate on [Ca2+]i and the release of NO in cultured endothelial cells of the calf middle cerebral artery].

The effect of 8-(N,N'-diethylamino)-n-octyl-3,4,5-trimethoxybenzoate(TMB-8) on [Ca2+]i and the release of NO in cultured endothelial cells of the calf middle cerebral artery was studied by a system of measurement of AR-CM-MIC, using Fura-2/AM as a fluorescent indicator and the oxy-haemoglobin method. In the presence of extracellular Ca2+ 1.3 mmol.L-1, the resting [Ca2+]i and the extinction difference(delta E) of between 401 and 410 nm were not changed by TMB-8 12.5 and 25 mumol.L-1, but were increased by TMB-8 50 and 100 mumol.L-1. The rise of delta E induced by TMB-8 50 and 100 mumol.L-1 was blocked completely by L-NAME. The elevation of [Ca2+]i was related to the release of NO. The result suggested that TMB-8 increased resting [Ca2+]i of endothelial cells of the calf middle cerebral artery and induced NO release.