Exercise changes regional vascular control by commissural NTS in spontaneously hypertensive rats

Autor(es)

Ogihara, Cristiana A. ^[1] ; Schoorlemmer, Gerhardus H. M. ^[1] ; Levada, Adriana C. ^[2] ; Pithon-Curi, Tania C. ^[2] ; Curi, Rui ^[2] ; Lopes, Oswaldo Ubriaco ^[1] ; Colombari, Eduardo ^[1] ; Sato, Monica A. ^[3]

Afiliação do(s) autor(es)

^[1] Univ Fed Sao Paulo, Dept Physiol, Sao Paulo - Brazil

^[2] Univ Sao Paulo, Inst Biomed Sci, Dept Physiol, Sao Paulo - Brazil

^[3] Fac Med ABC, Dept Physiol, BR-09060650 Santo Andre, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: AMERICAN JOURNAL OF PHYSIOLOGY-REGULATORY INTEGRATIVE AND COMPARATIVE PHYSIOLOGY; v. 299, n. 1, p. R291-R297, JUL 2010.
• Citações Web of Science: 12

Resumo

Ogihara CA, Schoorlemmer GHM, Levada AC, Pithon-Curi TC, Curi R, Lopes OU, Colombari E, Sato MA. Exercise changes regional vascular control by commissural NTS in spontaneously hypertensive rats. Am J Physiol Regul Integr Comp Physiol 299: R291-R297, 2010. First published April 21, 2010; doi: 10.1152/ajpregu.00055.2009.-Inhibition of the commissural nucleus of the solitary tract (commNTS) induces a fall in sympathetic nerve activity and blood pressure in spontaneously hypertensive rats (SHR), which suggests that this subnucleus of the NTS is a source of sympathoexcitation. Exercise training reduces sympathetic activity and arterial pressure. The purpose of the present study was to investigate whether the swimming exercise can modify the regional vascular responses evoked by inhibition of the commNTS neurons in SHR and normotensive Wistar-Kyoto (WKY) rats. Exercise consisted of swimming, 1 h/day, 5 days/wk for 6 wks, with a load of 2% of the body weight. The day after the last exercise session, the rats were anesthetized with intravenous alpha-chloralose, tracheostomized, and artificially ventilated. The femoral artery was cannulated for mean arterial pressure (MAP) and heart rate recordings, and Doppler flow probes were placed around the lower abdominal aorta and superior mesenteric artery. Microinjection of 50 mM GABA into the commNTS caused similar reductions in MAP in swimming and sedentary SHR (-25 +/- 6 and -30 +/- 5 mmHg, respectively), but hindlimb vascular conductance increased twofold in exercised vs. sedentary SHR (54 +/- 8 vs. 24 +/- 5%). GABA into the commNTS caused smaller reductions in MAP in swimming and sedentary WKY rats (-20 +/- 4 and -16 +/- 2 mmHg). Hindlimb conductance increased fourfold in exercised vs. sedentary WKY rats (75 +/- 2% vs. 19 +/- 3%). Therefore, our data suggest that the swimming exercise induced changes in commNTS neurons, as shown by a greater enhancement of hindlimb vasodilatation in WKY vs. SHR rats in response to GABAergic inhibition of these neurons. (AU)

• Processo FAPESP: 06/60842-1 - Controle hemodinâmico exercido por áreas bulbares em ratos espontaneamente hipertensos e Wistar-Kyoto submetidos ao treinamento físico
• Beneficiário: Monica Akemi Sato
• Modalidade de apoio: Auxílio à Pesquisa - Regular