Studies on the mechanism of action of 1-(2-methyl-3-hydroxy-5-hydroxy-methyl-4-pyridyl)-6,7-dihydroxy-1,2,3, 4- tetrahydroisoquinoline (PTIQ) on blood pressure in the anesthetized dog.
The mechanism of action of PTIQ in lowering the arterial blood pressure in the anesthetized dog was studied using pharmacological and physiological techniques. The hypotensive activity of PTIQ was significantly inhibited by pretreatment with bilateral vagotomy, propranolol, prazosin and mecamylamine. Pretreatment with either yohimbine or reserpine had no significant effect on PTIQ activity. PTIQ produced a significant decrease in the force of contraction of myocardial tissue and a transient increase in the aortic blood flow of the anesthetized dog. These results indicate a multiplicity of action of PTIQ in controlling arterial blood pressure.
SIU Lab, Silver Spring, MD 20907-7433.
P M
PM
Siu
J A
JA
Vick
D000758:Anesthesia; D000818:Animals; D001794:Blood Pressure / Q000187:drug effects*; D003326:Coronary Circulation / Q000187:drug effects; D004285:Dogs; D005260:Female; D006321:Heart / Q000187:drug effects; D006339:Heart Rate / Q000187:drug effects; D066298:In Vitro Techniques; D008297:Male; D009200:Myocardial Contraction / Q000187:drug effects; D009281:Naphthalenes / Q000494:pharmacology*; D011224:Prazosin / Q000494:pharmacology; D011433:Propranolol / Q000494:pharmacology; D011976:Receptors, Muscarinic / Q000187:drug effects; D012110:Reserpine / Q000494:pharmacology; D044005:Tetrahydroisoquinolines; D013764:Tetrahydronaphthalenes / Q000494:pharmacology*; D014628:Vagotomy; D015016:Yohimbine / Q000494:pharmacology
D009281:Naphthalenes; D011976:Receptors, Muscarinic; D044005:Tetrahydroisoquinolines; D013764:Tetrahydronaphthalenes; D015016:Yohimbine; C046152:1-(2-methyl-3-hydroxy-5-hydroxymethyl-4-pyridyl)-6,7-dihydroxy-1,2-3,4-tetrahydroisoquinoline; D012110:Reserpine; D011433:Propranolol; D011224:Prazosin