Effect of prostaglandin E2 on vascular responses of the rabbit kidney to nerve stimulation and noradrenaline, in vitro and in situ

The effect of prostaglandin E₂ on vascular responses of the rabbit kidney to renal nerve stimulation and noradrenaline was examined $\text{in}$$\text{vitro}$ and $\text{in}$$\text{situ}$ as a test of the hypthesis that prostaglandins of the E series may be involved in the regulation of adrenergic neuroeffector transmission. Intraarterial administration of prostaglandin E₂ to the $\text{in}$$\text{vitro}$ kidney caused marked inhibition of vascular responses to nerve stimulation whereas the responses to noradrenaline were not significantly altered. In the $\text{in}$$\text{situ}$ preparation, vascular responses to both nerve stimulation and noradrenaline were inhibited by prostaglandin E₂ infusion, although its effect on responses to nerve stimulation was approximately twice that observed on responses to noradrenaline.It is concluded that prostaglandin E₂ acts primarily at a prejunctional level of adrenergic neuroeffector transmission in the kidney, although a postjunctional effect has also been observed.