Is the pressor response to strychnine centrally mediated?

Intravenous administration of strychnine (0.003-0.300 mg . kg-1) to curarized, chloralosed dogs induced hypertension and tachycardia. In spinal cord-transected dogs, intravenous administration of strychnine no longer elicited a rise in blood pressure and heart rate. Intracisternal injections of strychnine also produced hypertension and tachycardia but at lower doses. Similar results were obtained after intrathecal administration of strychnine in doses significantly different from those effective on intravenous and intracisternal administration. These findings suggest that the central nervous system may be involved in the haemodynamic changes induced by strychnine, but did not allow the site of action to be located.