Effect of captopril on intracellular pH in vascular smooth muscle cells.

AIM

To observe the effect of captopril (Cap) on intracellular pH (pHi) in aortic smooth muscle cells (ASMC).

METHODS

Cultured ASMC derived from rat and rabbit aortae were loaded with the fluorescent dye BCECF and pHi was determined using digital image processing method.

RESULTS

The pHi of untreated SHR and WKY rats were 7.37 +/- 0.29 and 7.19 +/- 0.31, respectively. Oral Cap decreased pHi (7.11 +/- 0.26, P < 0.05) and exaggerated pHi response to angiotensin II (Ang-II, 0.1 mumol.L-1) in ASMC of SHR rats vs WKY rats (0.14 +/- 0.05 vs 0.21 +/- 0.05 pH units, P < 0.01). Cap in vitro had no effect on Ang-II induced intracellular alkalinization in ASMC of rabbits.

CONCLUSION

Oral Cap inhibits Na+(-)H+ exchange activity in ASMC of SHR rats.