Effect of resveratrol on the erectile machinery is due to the underlying mechanisms of the alpha 1‐adrenoceptor activation (1097.2)

Abstract

The anococcygeus muscle is part of the erectile machinery in male rodents whose innervation is mainly due the autonomic system. Activation of alpha1‐adreneceptor triggers the production of reactive oxygen species (ROS). Resveratrol (RESV) is an antioxidant compound. Hypothesis: RESV may reduce the contractile responses stimulated by alpha‐1‐adrenergic agonist, phenylephrine (PE). It was evaluated the effect of RESV on the contractile response to PE on the rat anococcygeus muscle. Male Wistar rats (n=5‐7) were killed by cervical dislocation (Ethics Committee Approval: 019/2012), the anococcygeus muscle was isolated and suspended in an organ chamber bath to measure isometric contractions. Preparations were stimulated with PE (1 nmol/L to 100 mmol/L) before and after 20 min incubation with RESV or RESV plus different drugs: prazosin (Pz: 10‐8 mol/L); 2‐APB (10‐4 mol/L); GF109203X (0.5x10‐5mol/L) or atorvastatin (ATV: 10‐4mol/L). Analysis: Student paired t‐test or one‐way ANOVA, Newman‐Keuls post‐test. RESV (10‐4 mol/L) reduced maximum contraction (MC) stimulated with PE (to 69.3±1.1%). Pz (alpha1‐adrenoceptor antagonist) + RESV reduced this MC (to 55.8±4.7%, p<0.0001). 2‐APB (IP3 receptor antagonist) was effective on reducing MC (to 28.8±1.19, p<0,001). RESV+2‐APB also reduced ME (to 5.3±1.4%, p<0.0001). pD2 values were reduced under RESV+2‐APB incubation. Incubation with GF109203X (PKC inhibitor) was effective on reducing MC (to 40.5±7.3%, p<0.0001). pD2 values were also altered after GF109203X incubation. ATV (NADPH oxidase inhibitor) +RESV reduced MC (56.9±7.7%, p<0.0001). The signaling triggered through stimulation of PE on the alpha 1‐adrenoceptors are involved in the production of free radicals, which were sensitive to RESV.Grant Funding Source: Supported by CNPq/PIBIC, UNAERP