Reed B V, Tuma R F
Clin Exp Hypertens A. 1986;8(6):963-79. doi: 10.3109/10641968609044080.
The purpose of the study was to compare the peripheral vascular effects of the calcium blocker nifedipine (NF) in normotensive Wistar Kyoto (WKY; n = 25) rats and spontaneously hypertensive rats (SHR; n = 28). Male eighteen week old animals were anesthetized with pentobarbital (50 mg/kg i.p.) and subjected to the radioactive microsphere technique for measurement of systemic and regional hemodynamics. While NF (30 micrograms/kg i.v. or 100 micrograms/kg i.v.) was effective in reducing resistance in all sampled vascular beds of SHR and WKY, it reduced renal vascular resistance to a greater extent in the SHR than in WKY (p less than 0.025). The data suggested a similar strain-specific effect in the SHR coronary, stomach and brain vasculatures (0.12 less than p less than 0.16). By contrast, high dose NF had a preferential effect on the skeletal muscle vasculature of WKY (p less than 0.025 for blood flow, p less than 0.16 for resistance). The findings support the premise that each calcium blocker has unique regional effects that differ between SHR and WKY.
