Effects of the mammalian lignan, 2,3-dibenzylbutane-1,4-diol, on contraction and Ca 2+ mobilization induced by noradrenaline in rat aorta

Abstract

1. 1. In rat aorta, 2,3-dibenzylbutane-1,4-diol (DBB) inhibited noradrenaline (NA)-induced contraction in a concentration-dependent manner. The inhibitory effect of DBB was observed in verapamil-pretreated muscle, and did not differ from that in the high K + solution containing verapamil (1.0 μM). 2. 2. DBB inhibited not only contraction, but [Ca 2+] i elevation induced by NA (10 μM) with the same potency. 3. 3. The inhibitory effect of DBB on NA-induced contraction was reversed by methylene blue (3.2 μM) and enhanced by M&B 22,948 (10μM). 4. 4. DBB (100 μM) alone increased cyclic GMP levels. This effect was attenuated by methylene blue (3.2 μM) and augmented by M&B 22,948 (10 μM). 5. 5. From these results, the inhibitory effects of DBB on NA-induced contraction in rat aorta may be caused by an increase of cyclic GMP levels.