Decreased Arteriolar Endothelium-derived Relaxing Factor Production During the Development of Genetic Hypertension

In the present study, basal and stimulated production of endothelium-derived relaxing factor (EDRF) were examined in young (4—5 week-old) and mature (10—12 week-old) spontaneously hypertensive rats (SHR) and were compared with those of age-matched Wistar Kyoto (WKY) normotensive rats. N^w-nitro-L-arginine methyl ester (L-NAME) was used as a probe for basal EDRF production in vivo. We also determined the dose-response effects of acetylcholine (Ach, 10^?9-10^?5 M), sodium nitroprusside (NP, 10^?9-10^?5 M), and norepinephrine (NE)