Canadian Journal of Anesthesia, Vol 5, 137-153, Copyright © 1958 by Canadian Anesthesiologists' Society

Studies on the Cardiovascular Actions of Chlorpromazine. III. Effects on Cerebral Blood Flow, Blood Pressure, and Electrocorticogram, as Recorded Simultaneously

¹ Department of Pharmacology McGill University, Montreal, P.Q.

In curarized dogs under artificial respiration, it was observed that (a) chlorpromazine in high and repeated doses (5 to 20 mg./kg.) can induce marked fall in blood pressure, tachycardia, and increased cerebral blood flow; (b) previous injections of similar high doses of chlorpromazine do not abolish either the pressor responses or cortical stimulation (outbursts) induced by metrazol, and both agents appear rather to lead to enhanced cortical outbursts; (c) chlorpromazine also does not affect the cortical stimulation (E.E.G. changes) following injections of nikethamide, picrotoxin, or amphetamine, but antagonizes the blood pressure responses to these agents; (d) after ganglionic-blockade (anso-Iysen or hexamethonium) cortical changes induced by chlorpromazine are not prevented, but its depressor response is lessened by ansolysen, but on the contrary enhanced by hexamethonium; (e) after sympathetic blockade (hydergin) both the central stimulation and pressor responses to metrazol are prevented, but the depressor response to chlorpromazine is antagonized and combined hyderginmetrazol treatment appears to prevent the usually observed depressor effects of excessive chlorpromazine injections; and (f) diethazine appears to exert similar actions to those of chlorpromazine, but its effects are less sustained.

Note:

Supported in part by grants from Poulenc Ltd., Montreal.