title: Investigations into the pharmacological effects of spongiatriol.
abstract: Acute intraperitoneal doses of spongiatriol, a compound extracted from marine sponges, caused blood pressure but not heart rate to fall in conscious hypertensive rats in a dose-dependent manner up to 50 mg/kg at which dose mean blood pressure fell 24%. Diarrhoea also resulted. Chronic oral doses (50 mg/kg every 3 h) lowered blood pressure by 73 mmHg after 48 h in conscious hypertensive rats and caused severe diarrhoea. Spongiatriol was an atrial stimulant in vitro and this effect could be greatly reduced by prior reserpinization or by beta-adrenoceptor blockade. In anaesthetized cats spongiatriol (50 mg/kg i.p.) caused reductions in blood pressure (19%), heart rate (11%) and cardiac output (12%). Spongiatriol 10(-5) g/ml had no effect on the response to noradrenaline in isolated rat tail arteries, markedly inhibited the response of in vitro guinea-pig ilea to acetylcholine and had a slight potentiating effect on the response of in vitro rat fundus stomach to serotonin and prostaglandin E2.
mesh_terms: D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D002302:Cardiac Output / Q000187:drug effects; D002319:Cardiovascular System / Q000187:drug effects*; D003967:Diarrhea / Q000139:chemically induced; D004064:Digestive System / Q000187:drug effects*; D004224:Diterpenes / Q000494:pharmacology*; D006168:Guinea Pigs; D066298:In Vitro Techniques; D008297:Male; D008386:Marine Biology; D009200:Myocardial Contraction / Q000187:drug effects; D051381:Rats; D011919:Rats, Inbred Strains
chemical_list: D004224:Diterpenes; C035754:spongiatriol