![]() |
|
|
DJ Cushing and ML Cohen
Cardiovascular Research, Lilly Research Laboratories Eli Lilly and Company, Indianapolis, Indiana.
Serotonin (5-HT) is one important mediator of the coronary vasospasm and occlusion associated with thrombosis and atherosclerosis. 5-HT concentration-dependently contracted both canine and porcine coronary artery rings in vitro. In the dog, 5-HT-induced contraction was not blocked by either LY53857 (1 microM) or ketanserin (1 microM), but was blocked by the nonselective 5-HT receptor antagonist 1- naphthylpiperazine (1-NP) (100 nM), indicating 5-HT receptor involvement. Unlike the dog, both LY53857 (1 microM) and ketanserin (30 nM) antagonized 5-HT-induced contraction in pig arteries. Dissociation constants for LY53857 and ketanserin in porcine arteries were compared with those in rat jugular vein, a tissue possessing a well characterized 5-HT2 receptor. Both LY53857 (3 nM) and ketanserin (3 nM) antagonized 5-HT-induced contraction in rat jugular vein; however, the affinities of LY53857 and ketanserin in the rat jugular vein were significantly higher than those in the pig coronary. The rank order contractile potency for 5-HT, (alpha Me-5-HT) and sumatriptan in porcine coronary artery was consistent with that established for a 5- HT2 receptor, whereas the rank order potency in canine coronary artery indicated non-5-HT2 receptor involvement. Sumatriptan, a 5-HT1D receptor-selective agonist, was equieffective to 5-HT in contracting the canine coronary artery, a response inhibited by 1-NP (100 nM). Sumatriptan failed to contract either the pig coronary or rat jugular vein. In summary, significant differences exist in the 5-HT receptors that mediate contraction between the canine and porcine coronary artery.(ABSTRACT TRUNCATED AT 250 WORDS)
This article has been cited by other articles:
![]() |
T. Watanabe, R. Pakala, S. Koba, T. Katagiri, and C. R. Benedict Lysophosphatidylcholine and Reactive Oxygen Species Mediate the Synergistic Effect of Mildly Oxidized LDL With Serotonin on Vascular Smooth Muscle Cell Proliferation Circulation, March 13, 2001; 103(10): 1440 - 1445. [Abstract] [Full Text] [PDF] |
||||
![]() |
Q. Yang, E. Scalbert, P. Delagrange, P. M. Vanhoutte, and S. T. O'Rourke Melatonin potentiates contractile responses to serotonin in isolated porcine coronary arteries Am J Physiol Heart Circ Physiol, January 1, 2001; 280(1): H76 - H82. [Abstract] [Full Text] [PDF] |
||||
![]() |
H. Movahedi and R. E. Purdy Pharmacological Characterization of the "Silent" 5-Hydroxytryptamine1B-like Receptors of Rabbit Ear Artery J. Pharmacol. Exp. Ther., November 1, 1997; 283(2): 653 - 660. [Abstract] [Full Text] |
||||