Functional interactions between neuronal AT(1) and AT(2) receptors

Angiotensin II (Ang II), via the activation of the AT(1) and AT(2) receptors regulates electrophysiological responses of catecholaminergic neurons. This study was designed to determine if functional interactions between AT(1) and AT(2) receptors exist in a single neuron. Ang II caused two unique electrophysiological responses characteristic of receptor crosstalk. First, Ang II elicited an AT(1) receptor-mediated decrease in I-K followed by an AT(2) receptor-mediated increase in I-K. Second, Ang II elicited an AT(2) receptor-mediated increase in I-K followed by an AT(1) receptor-mediated decrease in I-K. AT(1) and AT(2) receptors were co-localized on the catecholaminergic neurons. suggest, for the first time, the existence of a crosstalk between Ang II receptor subtypes that may be significant in the physiological activity of catecholaminergic neurons.