Isolated human cystic artery: responses to common agonist and antagonist drugs.
The extramural artery of the human gall bladder (cystic artery), a small artery (outside diameter 1.3 +/- 0.03 mm) with a thick muscular wall and little elastin within the tunica media, has catecholamine fluorescence localized to the adventitia-medial border. Isolated helical strips of the artery are responsive to norepinephrine (NE), 5-hydroxytryptamine (5HT) and vasopressin (VP) at low concentrations, but at the maximal frequency of transmural electrical stimulation used (16 Hz), the response is only 10--20% of the NE maximum response. Phentolamine (2.7 X 10(-6) M) antagonized responses to NE, 5HT and, to a lesser degree, electrical stimulation and these actions are similar to those reported in other mammalian tissue. In vitro use of reserpine (1.6 X 10(-5) M) and guanethidine (4 X 10(-5) M) also produced effects which were predictable from effects observed in other mammalian tissues; except reserpine diminished responsiveness to NE and 5HT and guanethidine enhanced responses to the early administered electrical stimulation.
D000328:Adult; D000368:Aged; D001158:Arteries / Q000187:drug effects; D004558:Electric Stimulation; D005260:Female; D005704:Gallbladder / Q000098:blood supply*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009131:Muscle, Smooth, Vascular / Q000187:drug effects* / Q000502:physiology; D009638:Norepinephrine / Q000494:pharmacology; D012701:Serotonin / Q000494:pharmacology; D014667:Vasopressins / Q000494:pharmacology
D014667:Vasopressins; D012701:Serotonin; D009638:Norepinephrine