Angiotensin‐Induced Cyclic GMP Production Is Mediated by Multiple Receptor Subtypes and Nitric Oxide in N1E‐115 Neuroblastoma Cells

Abstract

Angiotensin II (AngII) elicited a rapid and dose-related production of intracellular cyclic GMP (cGMP) in murine neuroblastoma N1E-115 cells. The agonist-induced rise in cGMP levels was blocked in a monophasic fashion by the AT1-selective antagonist DuP 753 or the nonselective antagonist [Sarc1,Ile8]-AngII, and both antagonists produced complete inhibition of the cGMP response elicited by submaximal concentrations of AngII. In contrast, the AT2-selective antagonist CGP 42112A inhibited the cGMP response biphasically. At lower antagonist concentrations, agonist-induced cGMP production was only partially inhibited, whereas complete inhibition was observed only when the concentration of CGP 42112A was increased sufficiently to interact with both AT1 and AT2 receptor subtypes. AngII also increased inositol trisphosphate (InsP3) levels in N1E-115 cells. However, the InsP3 response was mediated exclusively by the AT1 receptor subtype because it was inhibited by lower, AT1-selective concentrations of DuP 753, whereas only higher, nonselective concentrations of CGP 42112A were effective. Finally, the stimulatory effects of AngII on cGMP production appeared to be mediated by the intracellular formation of nitric oxide in that they were attenuated by the nitric oxide synthase inhibitor, N-monomethyl-L-arginine. Collectively, these results suggest that the AngII-elicited rise in cGMP levels may require an interaction between AT1-mediated mobilization of intracellular Ca2+, as well as some partial role of AT2 receptors.

Development of polyclonal antibodies against angiotensin type 2 receptors.

“…Recently, it has been reported that the AT2 receptor subtype may mediate inhibition of cGMP production in neuron-enriched cultures from neonatal rats (10) and PC12 cells (11). On the other hand, AngII has been reported to increase cGMP levels in neuroblastoma cells, an effect that appears to be mediated by multiple receptor subtypes and nitric oxide production (12). Multiple effects of AngII on ionic conductances may also be mediated by AT2 receptors (13).…”

Contribution of bradykinin and nitric oxide to AT2 receptor‐mediated differentiation in PC12 W cells

“…In other neuronal cell types Ang II has been shown to increase cyclic GMP production through activation of angiotensin receptor subtypes that are distinct from the AT 2 receptor. For example, in N1E-115 neuroblastoma cells the Ang II-induced production of cyclic GMP was mediated by an AT 1 receptor-dependent mechanism (Zarahn et al 1992), whereas in neuroblastoma Neuro-2A cells a non-AT 1 and non-AT 2 receptor was responsible for this effect (Chaki and Inagami 1993). A decrease in the basal cyclic GMP levels induced by Ang II was observed in neurone cultures derived from neonatal rat brains which contain predominantly AT 2 receptors but also a smaller population of AT 1 receptors.…”

Interaction of Endothelial Nitric Oxide and Angiotensin in the Circulation

“…In Vitro Studies. It was demonstrated that ANG II elicited an intracellular cyclic GMP production possibly mediated by NO in murine neuroblastoma NIE-115 cells (Zarahn et al, 1992) and neuroblastoma neuro-2A cells (Chaki and Inagami, 1993). The former authors suggested that AT 1 receptor-mediated mobilization of intracellular Ca 2ϩ is involved in this response, whereas the latter authors concluded that the newly found ANG II receptor may be responsible for activation of guanylyl cyclase that is mediated by NO formed through Ca 2ϩ influx.…”