Effects of chronic taurine treatment on reactivity of the rat aorta

The effects of chronic taurine treatment on the reactivity of the aorta for m male Wistar-Kyoto rats were investigated. Contractile responses to norepi nephrine (NE) and potassium chloride (KCl) were attenuated in aortic rings from taurine-treated rats as compared to controls both in the absence and p resence of endothelium. However, the degree of attenuation was greater in e ndothelium-intact tissues contracted with NE. Acetylcholine (Ach)-induced r elaxation responses were augmented in endothelium-intact vessels from rats supplemented with taurine compared to the responses observed in control pre parations. Relaxation responses of the aortae from control and taurine-trea ted rats to sodium nitroprusside (SNP) were not different from each other. Our results suggest that taurine treatment attenuates vascular contractilit y nonspecifically and this effect is partly mediated via the endothelium.