TY - JOUR

T1 - Exercise training reverses alterations in Kv and BKCa channel molecular expression in thoracic aorta smooth muscle cells from spontaneously hypertensive rats

AU - Li, Zhencheng

AU - Lu, Ni

AU - Shi, Lijun

N1 - (Ekstern)

PY - 2014

Y1 - 2014

N2 - Previous studies have shown that exercise training influences potassium channel protein expression in arteries. The purpose of this study was to investigate the effect of exercise training on alterations in voltage-gated potassium channels (Kv) and large-conductance, calcium-activated potassium channels (BKCa) in thoracic aorta smooth muscle cells from spontaneously hypertensive rats (SHRs). Male SHRs were randomly assigned to a sedentary group (SHRSED) and exercise training group (SHR-EX). Age-matched Wistar-Kyoto rats (WKYs) were used as controls. After 8 weeks of aerobic exercise training, blood pressure was significantly lower in the SHR-EX group than in the SHR-SED group. Exercise training increased the contribution of the Kv 1.2 and Kv 1.5 channels and decreased the contribution of BKCa channel to resting tone in the SHR-EX group compared to the SHR-SED group as indicated by vessel contractility experiments. Immunohistochemistry and Western blotting showed that Kv 1.2 and Kv 1.5 channel expression was significantly lower in the SHR-SED group than in the WKY group and exercise training attenuated this reduction. BKCa α-subunit expression was statistically unchanged between the groups; however, β1-subunit expression was reduced significantly by exercise training in the SHR-EX group compared to the SHR-SED group. These data suggest that exercise training reverses the pathological expression of the Kv 1.2, Kv 1.5, and BKCa channels in aortic myocytes from SHRs. This is one of the favorable effects of exercise training on large conduit arteries.

AB - Previous studies have shown that exercise training influences potassium channel protein expression in arteries. The purpose of this study was to investigate the effect of exercise training on alterations in voltage-gated potassium channels (Kv) and large-conductance, calcium-activated potassium channels (BKCa) in thoracic aorta smooth muscle cells from spontaneously hypertensive rats (SHRs). Male SHRs were randomly assigned to a sedentary group (SHRSED) and exercise training group (SHR-EX). Age-matched Wistar-Kyoto rats (WKYs) were used as controls. After 8 weeks of aerobic exercise training, blood pressure was significantly lower in the SHR-EX group than in the SHR-SED group. Exercise training increased the contribution of the Kv 1.2 and Kv 1.5 channels and decreased the contribution of BKCa channel to resting tone in the SHR-EX group compared to the SHR-SED group as indicated by vessel contractility experiments. Immunohistochemistry and Western blotting showed that Kv 1.2 and Kv 1.5 channel expression was significantly lower in the SHR-SED group than in the WKY group and exercise training attenuated this reduction. BKCa α-subunit expression was statistically unchanged between the groups; however, β1-subunit expression was reduced significantly by exercise training in the SHR-EX group compared to the SHR-SED group. These data suggest that exercise training reverses the pathological expression of the Kv 1.2, Kv 1.5, and BKCa channels in aortic myocytes from SHRs. This is one of the favorable effects of exercise training on large conduit arteries.

KW - Faculty of Science

KW - Potassium channels

KW - Spontaneously hypertensive rat

KW - Exercise training

KW - Thoracic aorta

UR - http://europepmc.org/abstract/med/25661478

U2 - 10.1159/000369928

DO - 10.1159/000369928

M3 - Journal article

C2 - 25661478

VL - 51

SP - 447

EP - 457

JO - Journal of Vascular Research

JF - Journal of Vascular Research

SN - 1018-1172

IS - 6

ER -