RESUMEN
BACKGROUND: Cells rely on gap junctions for intercellular communication, which is important for growth and contractility. The present study was conducted to test the hypothesis that contractile responses in aortic rings from two-kidney, one clip (2K1C) hypertensive rats are more dependent on gap junctional communication compared to those from normotensive rats. METHODS: 2K1C hypertension was induced by clipping the left renal artery and age-matched rats received a sham operation. Heptanol and octanol were used as inhibitors of gap junctional activity. RESULTS: The contraction induced by phenylephrine or KCl was completely reversed by either heptanol or octanol, and the relaxant response to inhibitors was more enhanced in 2K1C hypertensive rats compared to sham-operated rats. Vessels from hypertensive rats also relaxed more to nifedipine when precontracted with KCl, although it did not differ in aortic segments contracted with phenylephrine in between normotensive and hypertensive rats. CONCLUSION: These results suggest that gap junctional communication and voltage-operated calcium channels are differentially regulated in 2K1C renal hypertension.
Asunto(s)
Ratas , AnimalesRESUMEN
BACKGROUND: Cells rely on gap junctions for intercellular communication, which is important for growth and contractility. The present study was conducted to test the hypothesis that contractile responses in aortic rings from two-kidney, one clip (2K1C) hypertensive rats are more dependent on gap junctional communication compared to those from normotensive rats. METHODS: 2K1C hypertension was induced by clipping the left renal artery and age-matched rats received a sham operation. Heptanol and octanol were used as inhibitors of gap junctional activity. RESULTS: The contraction induced by phenylephrine or KCl was completely reversed by either heptanol or octanol, and the relaxant response to inhibitors was more enhanced in 2K1C hypertensive rats compared to sham-operated rats. Vessels from hypertensive rats also relaxed more to nifedipine when precontracted with KCl, although it did not differ in aortic segments contracted with phenylephrine in between normotensive and hypertensive rats. CONCLUSION: These results suggest that gap junctional communication and voltage-operated calcium channels are differentially regulated in 2K1C renal hypertension.