![[Feedback]](/icons/banner/feedbackACT.gif){kind=icon}
![[For Subscribers]](/icons/banner/subscriberACT.gif){kind=icon}
![[Archive]](/icons/banner/archiveACT.gif){kind=icon}
![[Search]](/icons/banner/searchACT.gif){kind=icon}
![[Contents]](/icons/banner/tocACT.gif){kind=icon}
|
|
|
|
|
||
P Schoeffter and D Hoyer
Preclinical Research, Sandoz Ltd, Basel, Switzerland.
The 5-hydroxytryptamine (5-HT) receptor mediating endothelium-dependent relaxation of pig coronary arteries was characterized using a variety of 5-HT receptor agonists and antagonists. Unrubbed (with endothelium preserved) rings precontracted by prostaglandin F2 alpha in the presence of ketanserin relaxed in an endothelium-dependent manner to 5- HT, 5-carboxamidotryptamine and 5-methoxytryptamine with about equal potency and efficacy. By comparison, bufotenine, 3-(dimethylamino)ethyl- N-methyl-1H-indole-5-methane sulfonamide, (-)-alpha-methyl-5-HT,N,N- dipropyl-5-carboxamidotryptamine and 5-methoxy-3-(1,2,3,6-tetrahydro-4- pyridinyl)-1H indole were half-efficient and other drugs [in particular the 5-HT1A receptor agonist 8-hydroxy-2-(di-n-propylamino)tetralin] were inactive as agonists up to 0.1 mM. The effect of 5- carboxamidotryptamine was antagonized in an apparently competitive manner by 15 drugs. Among the most potent antagonists (mean pKB value) were the nonselective 5-HT receptor antagonists, methiothepin (7.30) and metergoline (6.86), the 5-HT1A/5-HT1D receptor ligand, 1-[2-(4- amino-phenyl)ethyl]-4-(3-trifluoromethylphenyl)-piperazine (7.02), the 5-HT1A/5-HT1B/5-HT1D receptor ligand, 7-trifluoromethyl-4-(4-methyl-1- piperazinyl)-pyrrolo[1,2,-a]quinoxaline 1 (6.73) and yohimbine (6.37). Selective ligands for 5-HT1A receptors were either inactive [8-hydroxy- 2-(di-n-propylamino)tetralin hydrobromide] or poorly active (spiperone, 4.44). Beta-adrenoceptor antagonists with affinity for 5-HT1A and 5- HT1B receptors weakly antagonized the effect of 5-carboxamidotryptamine (pKB values less than or equal to 5.32), as did the 5-HT1c/5-HT2 receptor antagonist, mesulergine (5.30) and the yohimbine isomer, corynanthine (4.85). Methysergide was clearly a noncompetitive antagonist.(ABSTRACT TRUNCATED AT 250 WORDS)
This article has been cited by other articles:
|
|
 |
|
  S. Takano, Y. Hoshino, L. Li, I. Matsuoka, T. Ono, and J. Kimura Dual Roles of 5-Hydroxytryptamine in Ischemia-Reperfusion Injury in Isolated Rat Hearts Journal of Cardiovascular Pharmacology and Therapeutics, March 1, 2004; 9(1): 43 - 50. [Abstract] [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]
|
|
|
|
 |
|
 G.-W. He and C.-Q. Yang Basal or Stimulated Release?: Evidence of EDRF (NO) Release by TP-Receptor Agonist U46619 Vascular and Endovascular Surgery, July 1, 1997; 31(4): 433 - 439. [Abstract] [PDF]
|
|
|
|
 |
|
 M. A. Moskowitz and C. Waeber Migraine Enters the Molecular Era Neuroscientist, May 1, 1996; 2(3): 191 - 200. [Abstract] [PDF]
|
|
|
|
 |
|
 G.-W. He, C.-Q. Yang, and A. Starr Overview of the Nature of Vasoconstriction in Arterial Grafts for Coronary Operations Ann. Thorac. Surg., March 1, 1995; 59(3): 676 - 683. [Abstract] [Full Text]
|
|
|
|
 |
|
 G.-W. He and C.-Q. Yang "Vasoactivators"--a New Concept for Naturally Secreted vasoconstrictor Substances Angiology, April 1, 1994; 45(4): 265 - 271. [Abstract] [PDF]
|
|
 |
 |
 |
|
 |
 |
 |
