Effect of sympathetic blockade on central prostaglandin E2-induced hyperthermia.
The mechanisms by which intracerebroventricular (i.v.t.) prostaglandin E2 (PGE2) produce hyperthermia in the rat were investigated. I.v.t. PGE2 produced dose-related increases in blood pressure, heart rate and rectal temperature which were significant with a dose of 0.5 ng. Oxygen consumption also increased and remained above baseline over an hour with 50 and 500 ng PGE2 doses. Ganglionic blockade with hexamethonium (20 mg/kg) attenuated the blood pressure and heart rate response to PGE2 but metabolic rate and rectal temperature increases were unchanged. Propranolol (2 mg/kg i.v.) decreased the heart rate response to PGE2 but had no significant effect on blood pressure, metabolic rate and rectal temperature responses. These results suggest a similar sensitivity of central receptors for mediating cardiovascular and metabolic rate/temperature increases but suggest that the mechanisms mediating these effects are separate.
Hoffman
W E
WE
Albrecht
R F
RF
Miletich
D J
DJ
D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D001831:Body Temperature / Q000187:drug effects*; D002490:Central Nervous System / Q000187:drug effects*; D015232:Dinoprostone; D006339:Heart Rate / Q000187:drug effects; D018738:Hexamethonium; D006584:Hexamethonium Compounds / Q000494:pharmacology; D007276:Injections, Intraventricular; D008297:Male; D010101:Oxygen Consumption / Q000187:drug effects; D011433:Propranolol / Q000494:pharmacology; D011458:Prostaglandins E / Q000494:pharmacology*; D051381:Rats; D011919:Rats, Inbred Strains; D013564:Sympathetic Nervous System / Q000187:drug effects*
D006584:Hexamethonium Compounds; D011458:Prostaglandins E; D018738:Hexamethonium; D011433:Propranolol; D015232:Dinoprostone