Regularly swimming exercise modifies opioidergic neuromodulation in rostral ventrolateral medulla in hypertensive rats

Autor(es)

Almeida, Roberto L. ^[1] ; Ogihara, Cristiana A. ^[1] ; de Souza, Janaina S. ^[2] ; Oliveira, Kelen C. ^[2] ; Cafarchio, Eduardo M. ^[1] ; Tescaro, Larissa ^[1] ; Maciel, Rui M. B. ^[2] ; Giannocco, Gisele ^[2] ; Sato, Monica A. ^[1]

Afiliação do(s) autor(es)

^[1] Ctr Univ FMABC, Fac Med ABC, Dept Morphol & Physiol, Santo Andre, SP - Brazil

^[2] Univ Fed Sao Paulo, Dept Med, Sao Paulo, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Brain Research; v. 1774, JAN 1 2022.
• Citações Web of Science: 0

Resumo

Moderate exercise reduces arterial pressure (AP) and heart rate (HR) in spontaneously hypertensive rats (SHR) and changes neurotransmission in medullary areas involved in cardiovascular regulation. We investigated if regularly swimming exercise (SW) affects the cardiovascular adjustments mediated by opioidergic neuromodulation in the RVLM in SHR and Wistar-Kyoto (WKY) rats. Rats were submitted to 6 wks of SW. The day after the last exercise bout, alpha-chloralose-anesthetized rats underwent a cannulation of the femoral artery for AP and HR recordings, and Doppler flow probes were placed around the lower abdominal aorta and superior mesenteric artery. Bilateral injection of endomorphin-2 (EM-2, 0.4 mmol/L, 60 nL) into the RVLM increased MAP in SW-SHR (20 +/- 4 mmHg, N = 6), which was lower than in sedentary (SED)-SHR (35 +/- 4 mmHg, N = 6). The increase in MAP in SW-SHR induced by EM-2 into the RVLM was similar in SED- and SW-WKY. Naloxone (0.5 mmol/L, 60 nL) injected into the RVLM evoked an enhanced hypotension in SW-SHR (-66 +/- 8 mmHg, N = 6) compared to SED-SHR (-25 +/- 3 mmHg, N = 6), which was similar in SED- and SW-WKY. No significant changes were observed in HR after EM-2 or naloxone injections into the RVLM. Changes in hindquarter and mesenteric conductances evoked by EM-2 or naloxone injections into the RVLM in SW- or SED-SHR were not different. Mu Opioid Receptor expression by Western blotting was reduced in SW-SHR than in SED-SHR and SW-WKY. Therefore, regularly SW alters the opioidergic neuromodulation in the RVLM in SHR and modifies the mu opioid receptor expression in this medullary area. (AU)

• Processo FAPESP: 10/50351-6 - Estudo da neuromodulacao opiodergica sobre o controle hemodinamico exercido por areas bulbares em ratos hipertensos e normotensos submetidos ao exercicio fisico.
• Beneficiário: Monica Akemi Sato
• Modalidade de apoio: Auxílio à Pesquisa - Regular