Changes in pulse wave velocity in hypertensive patients treated with perindopril for 48 months (original) (raw)

2002, American Journal of Hypertension

The structural basis of reduced arterial distensibility in Dahl salt-sensitive (DS) rats was investigated. 3-month old male DS rats received normal (0.7% NaCl) or highsodium (2% NaCl) diet for 3 months. Dahl salt-resistant (DR) rats on normal or high-sodium diet were controls. Pressure-volume (distensibility) relationships were measured in excised, in vitro perfused segments of right carotid arteries (CA). The left CA of rats was perfused in situ with papaverine followed by fixative at 100 mmHg and then embedded for morphometric measurements. The average monthly tail SBP of DS rats on normal and high-sodium diet, 125Ϯ2 (Nϭ10) and 142Ϯ4 (Nϭ10)mmHg, were increased (pϽ0.05 and Ͻ0.01), compared to that of DR rats, 116Ϯ2 (Nϭ10) and 115Ϯ2 (Nϭ10). Compared to controls, CA pressure-volume curves of DS rats on normal and high-sodium diet were shifted toward the pressure axis (pϽ0.05 for both comparisons), but stress-strain relationships of CA were similar in DS and DR rats. Reduced distensibility of CA of DS rats was accompanied by increased lumen diameter (909Ϯ24m, meanϮSE, Nϭ15, vs. 805Ϯ34, Nϭ18, pϽ0.01) and increased thickness of media (64Ϯ3m vs. 54Ϯ3, pϽ0.02) and of elastic lamellae(1.1Ϯ0.06m, Nϭ11, vs. 0.7Ϯ0.04, Nϭ11, pϽ0.05) ,wall-to-lumen ratio being unchanged. High-salt diet had no effect on either distensibility or dimensions of CA in DS and DR rats. Reduced distensibility of CA in DS rats is due to dilatation not fully compensated for by increased medial thickness. Altered structure and function of CA in DS rats are either genetically determined or adaptation to salt-sensitivity occurs also on "normal" sodium diet.