Vascular effects of R-568 in MVB from WKY and SHR rats.
Mesenteric vascular beds (MVB) from 8-week old WKY and SHR rats were isolated and prepared as described in Methods. PP at approximately 120 mmHg was maintained by continuous infusion with NA (10 μM and 3 μM in WKY and SHR rats, respectively). (A) and (B) Representative tracings of vasodilator responses to submaximal ACh dose (1 μM) and to increasing concentrations of R-568 (10 nM—30 μM) in WKY (A) and SHR (B) are shown. Each symbol represents the start of a 4-min perfusion. (C) Dose-response curves for R-568-induced vascular effects were obtained from MVB of WKY and SHR. Results are the mean ± SEM of 7 (WKY) and 6 (SHR) independent experiments. Data from each curve were normalized by defining 100% as the initial steady state PP and 0% as the maximal reduction in PP obtained in WKY treated with 1 μM ACh. *p < 0.01 vs respective values.