Ogihara, Cristiana A.
Schoorlemmer, Gerhardus H. M.
Lazari, Maria de Fatima M.
Lopes, Oswaldo U.
Sato, Monica A.
Total Authors: 7
 FMABC, Dept Physiol, BR-09060650 Santo Andre, SP - Brazil
 Fed Univ Sao Paulo UNIFESP, Dept Physiol, BR-04023901 Sao Paulo - Brazil
 Fed Univ Sao Paulo UNIFESP, Dept Pharmacol, BR-04044020 Sao Paulo - Brazil
 Sao Paulo State Univ UNESP, Sch Dent, Dept Pathol & Physiol, BR-14801385 Araraquara, SP - Brazil
Total Affiliations: 4
BIOMED RESEARCH INTERNATIONAL;
Web of Science Citations:
Exercise training reduces sympathetic activity in hypertensive humans and rats. We hypothesized that the swimming exercisewould change the neurotransmission in the rostral ventrolateral medulla (RVLM), a key region involved in sympathetic outflow, and hemodynamic control in spontaneously hypertensive rats (SHR) and Wistar-Kyoto (WKY) rats. Bilateral injections of kynurenic acid (KYN) were carried out in the RVLM in sedentary- (S-) or exercised- (E-) SHR and WKY rats submitted to swimming for 6 weeks. Rats were alpha-chloralose anesthetized and artificially ventilated, with Doppler flow probes around the lower abdominal aorta and superior mesenteric artery. Injections into the RVLM were made before and after i.v. L-NAME (nitric oxide synthase, NOS, inhibitor). Injections of KYN into the RVLM elicited a major vasodilation in the hindlimbmore than in the mesenteric artery in E-SHR compared to S-SHR, but similar decrease in arterial pressure was observed in both groups. Injections of KYN into the RVLM after i.v. L-NAME attenuated the hindlimb vasodilation evoked by KYN and increased the mesenteric vasodilation in ESHR. Swimming exercise can enhance the hindlimb vasodilation mediated by peripheral NO release, reducing the activation of neurons with EAA receptors in the RVLM in SHR. (AU)