Effect of antihypertensive treatment on peripheral nerve vasculature in spontaneously hypertensive rats.

The influence of hypertension and of treatment with the dihydropyridine-type Ca+2 antagonist nicardipine on peripheral nerve vasculature were investigated in spontaneously hypertensive rats (SHR). Male SHR were treated from the 16th to the 26th week of age with vehicle (control group), with nicardipine, at the hypotensive dose of 3 mg/kg/day, or at the nonhypotensive dose of 0.1 mg/kg/day or with an equihypotensive dose (10 mg/kg/day) of the nondihydropyridine-type vasodilator hydralazine. Age-matched normotensive Wistar-Kyoto (WKY) rats were left untreated and used as normotensive reference animals. In SHR a significant increase of systolic pressure values accompanied by sciatic nerve microvascular changes, involving primarily interfascicular arteries and to a lesser extent intrafascicular arteries, was observed. Treatment with the hypotensive dose of nicardipine countered hypertension-dependent microvascular changes occurring in both interfascicular and intrafascicular arteries. The nonhypotensive dose ...