Difference expression of Cx37 and Cx40 of arteries in spontaneously hypertensive rats / 重庆医学

Objective To investigate the change of connexin (Cx) in mesenteric artery (MA) and aorta of spontaneously hyper‐tensive rats (SHR) and normotensive rats .Methods Quantitative RT‐PCR and Werstern blot technique were used to compare the difference in the expression of Cx37 and Cx40 mRNA and protein in MA and aorta of SHR and normotensive rats .Results The level of Cx37 mRNA expression in MA from SHR was decreased compared with that of the normotensive rats (P0 .05) .The expression of Cx37 protein in MA from SHR was decreased compared with that of the normotensive rats (P0 .05) . Conclusion Hypertension may could decrease gap junctional communication in cells of MA and aorta from SHR by the downregu‐lation of the expression of Cx37 and/or Cx40 .

Inhibitory effects of flufenamic acid on gap junction of vascular smooth muscle cells in guinea pig / 重庆医学

Objective To investigate the influence of flufenamic acid (FFA) on gap junction intercellular communication in vascu-lar smooth muscle cells(VSMC) in situ of acutely isolated arteriole segments .Methods Whole-cell patch clamp recordings were used to study the effects of FFA on membrane input capacitance (Cinput ) ,membrane input conductance(Ginput ) or membrane input re-sistance(Rinput ) of VSMCs embedded in arteriole segments .Results FFA concentration-dependently and reversibly suppressed Ginput or increased Rinput ,with an IC50 of 56 and 33μmol/L in acutely isolated mesenteric artery(MA) and brain artery(BA) segments re-spectively .There was not significant difference between MA and BA (P> 0 .05) .After application of FFA (≥ 300 μmol/L) ,the Cinput ,Ginput and Rinput of the in situ cells were very close to the respective dispersed cell in MA and BA .Conclusion FFA is a reversi-ble gap junction blocker ,achieving a complete electrical isolation of the recorded VSMC at ≥300 μmol/L .FFA suggesting a homo-geneous property of the gap junctions between MA and BA .