title: Differential effects of prazosin and rauwolsin on the release of prostaglandins I2 and E2 from the perfused mesenteric arterial bed of the rabbit following nerve stimulation.
abstract: Sympathetic nerve stimulation of the perfused mesenteric arterial bed of the rabbit, in vitro, increases the secretion of prostaglandin (PG)I2 and PGE2. Prazosin (4.8 X 10(-6) M), an alpha 1 adrenergic receptor antagonist, inhibited this increase in release of PGI2 but not of PGE2 whereas rauwolsin (10(-7) M), and alpha 2 adrenergic receptor antagonist, inhibited the increase in release of PGE2 but not PGI2. Prazosin  (10(-6) M) completely blocked the vasoconstrictor response to nerve stimulation, and to norepinephrine and phenylephrine administration, suggesting there to be little of an alpha 2 adrenergic receptor component in this response. It is concluded that the increase in PGI2 release allows the activation of alpha1 adrenergic receptors and is therefore post-junctional in origin, whereas the increase in PGE2 release following the activation of alpha 2 adrenergic receptors and may be pre- and/or post-junctional in origin.
mesh_terms: D015121:6-Ketoprostaglandin F1 alpha / Q000378:metabolism; D000818:Animals; D015232:Dinoprostone; D004558:Electric Stimulation; D011464:Epoprostenol / Q000378:metabolism*; D007213:Indomethacin / Q000494:pharmacology; D008297:Male; D008638:Mesenteric Arteries / Q000187:drug effects / Q000294:innervation / Q000378:metabolism*; D009638:Norepinephrine / Q000494:pharmacology; D010656:Phenylephrine / Q000494:pharmacology; D011224:Prazosin / Q000494:pharmacology*; D011453:Prostaglandins / Q000378:metabolism*; D011458:Prostaglandins E / Q000378:metabolism*; D011799:Quinazolines / Q000494:pharmacology*; D011817:Rabbits; D014661:Vasoconstriction / Q000187:drug effects; D015016:Yohimbine / Q000494:pharmacology*
chemical_list: D011453:Prostaglandins; D011458:Prostaglandins E; D011799:Quinazolines; D010656:Phenylephrine; D015016:Yohimbine; D015121:6-Ketoprostaglandin F1 alpha; D011464:Epoprostenol; D015232:Dinoprostone; D009638:Norepinephrine; D011224:Prazosin; D007213:Indomethacin