Endothelins stimulate XXXX accumulation in the isolated @entity35 anterior pituitary gland: possible involvement of @entity11081 receptor activation and @entity1421 production.

@entity268 @entity1672 @entity1421 @entity20929 @entity11081 @entity1826 @entity2918 @entity1922 @entity4770 @entity1919 @entity1827 @entity11344 @entity35 @entity3352 @entity13071
Effects of @entity1827 ( @entity1827 ) and @entity1826 ( @entity1826 ) on @entity1919 ( @entity268 ) levels were studied in the isolated @entity35 anterior and intermediate-posterior pituitary slices. In the anterior pituitary, @entity1827 increased @entity268 levels in a concentration-dependent manner (10(-7)-10(-5) M). @entity1826 also increased the levels at the same concentration range, but @entity1827 was more potent than @entity1826 at an approximate ED50, 10(-6) M. The stimulatory effects of @entity20929 (10(-6) M) on @entity268 levels were antagonized by the @entity11081 receptor antagonist @entity11344 , 2 x 10(-6) M, and the ETB receptor agonist @entity13071 evoked only a weak increase in @entity268 levels. Moreover, the effects of @entity20929 were completely abolished by the cyclooxygenase inhibitor @entity3352 , 2 x 10(-5) M. On the other hand, among @entity2918 , @entity1421 ( @entity1421 ) increased @entity268 levels in a concentration-dependent manner (10(-7)-10(-5) M), whereas @entity1672 and @entity4770 did not exhibit such effects. @entity1421 levels were increased by application of @entity1827 (10(-8)-10(-5) M). The @entity1827 -induced @entity1421 accumulation was strongly inhibited by @entity3352 and @entity11344 , but not by treatment with pertussis toxin (100 ng/ml, 6 hr). Treatment with the phosphodiesterase inhibitor @entity1922 also elevated the @entity268 level by approximately 9-fold above the basal @entity268 level. After @entity1922 , @entity1827 failed to increase @entity1421 and @entity268 levels. In the intermediate-posterior pituitary, @entity20929 did not affect @entity268 levels. The results suggest that endothelins increase @entity268 levels via @entity11081 receptor activation interacting with the pertussis toxin-insensitive G-protein, in which @entity1421 production is involved in the @entity35 anterior pituitary, whereas endothelins lack these effects in the intermediate-posterior pituitary.
