The Effect Of The Blockers On Gap Junction Between Cerebral Arteriolar Electrophysiological In Wistar And Spontaneously Hypertensive Rats

Objective: This study compared Wistar rat with spontaneously hypertensive rat (SHR) on theelectrophysiology and coupling force of the smooth muscle cells in the cerebral arteriolar segments observethe influence of18β-glycyrrhetinic acid(18β-GA)、Niflumic Acid (NFA)、2-Aminoethoxydiphenyl borate(2-APB) on the gap junctions between the arterial smooth muscle cells.Methods: Whole-cell patch clamp recordings were used to observe the18β-GA`s impaction on thearteriolar segment membrane`s input capacitance (Cinput), input conductance (Ginput) and input resistance(Rinput) of the smooth muscle cells. The influence of the18β-GA、NFA、2-APB on gap junctionbetween cerebral arteriolar smooth muscle cells in Wistar rat,Results:(1) The Cinputand Ginputof the SHR arteriolar segment smooth muscle cells was much higher thanthe Wistar rats, there was significant difference (P <0.05).18β-GA concentration-dependently reduced Cinputand Ginput(or increase Rinput) on smooth muscle cells in arteriolar segment. IC50of18β-GA suppression`sGinputof the Wistar rat and SHR were5.1and5.3μmol/L respectively, there was not significantdifference(P>0.05). After application of18β-GA concentration≧100μmol/L, the Cinput, Ginputand Rinputof the single smooth muscle cells was very close.(2)18β-GA、NFA、2-APB concentration-dependently suppressed gap junction. IC50were5.1、6.6and4.1μmol/L respectively, there was not significant difference(P>0.05). After application of18β-GA,NFA,2-APB (≧100μmol/L), the Cinput, Ginputand Rinputin situ cells were very close to those indispersed cells.Conclusions: Gap junctional coupling is enhanced in the SHR cerebral arterial smooth muscle cells.18β-GA concentration-dependent inhibits Wistar rat`s and SHR cerebral arteriolar gap junctions betweenarterial smooth muscle cells. The inhibitory potency is similar between the two different rats.18βGA, NFAand2-APB concentration-dependent inhibits Wistar rat`s gap junction between arterial smooth musclecells and the inhibitory potency is similar.