Phorbol ester-stimulated 6-keto-prostaglandin F₁α in aortas from control and aldosterone—salt rats

Abstract

Objective: 

To assess the contribution of protein kinase C to the production of 6-keto-prostaglandin F₁α by stimulating protein kinase C directly.

Results: 

Phorbol myristate acetate caused a time-dependent increase in 6-keto-prostaglandin F₁α and thromboxane B₂. The time course was slower than for norepinephrine-stimulated production of these metabolites, but the pattern was similar, with thromboxane B₂ appearing before 6-keto-prostaglandin F₁α. The phorbol myristate acetate concentration—response curves for 6-keto-prostaglandin F₁α production for control-salt and aldosterone-salt hypertensive rats concentration-dependently. The staurosporine median inhibitory concentration for phorbol myristate acetate-stimulated 6-keto-prostaglandin F₁α production was twofold greater in aldosterone-salt hypertensive than in control-salt rats, but was similar for norepinephrine-stimulated 6-keto-prostaglandin F₁α.

Conclusion: 

Activation of protein kinase C results in increases in arachidonic acid metabolites, but alterations in this pathway do not seem to be responsible for production. The present data offer some support for the concept of direct coupling between the α₁-adrenoceptor and phospholipase A₂.