Effect of angiotensin II receptor subtype I on the firing rate in catecholaminergic tumor cells / 西安交通大学学报·英文版

ABSTRACT

Objective: To study the action of brain angiotensin II (Ang II) receptors and underlying intracellular mechanism in the catecholaminergic system (CATH) Methods: Action potentials (APs) of the primary co-cultured catecholaminergic tumor (CATH. a) cells were recorded with the whole-cell patch clamp configuration in current clamp mode. Expression of Ang II receptors subtypes (AT1 and AT2) was detected by RT-PCR technique. Results: The differentiated CATH. a cells represented a neuron-like characterization. All CATH, a cells expressed mRNA encoding both Ang II AT1 and AT 2 receptor subtypes. Ang II increased the firing rate in the CATH. a cells, which was inhibited completely by addition administration of the AT 1 but not AT2 receptor antagonist, and partially by using the inhibitors of signal molecules, U73122 (10 μmol · L-1), or KN-93 (10 μmol · L-1), or calphostin C (10 μmol · L-1). Conclusion: Ang II increases firing rate in CATH. a cells via AT1 receptor. The CATH. a cells expressing functional AT1 and AT2 receptor subtypes may be of general utility for the study of the Ang II receptor-induced modulation of brain catecholaminergic system.