SPINAL MECHANISMS INVOLVED IN THE CONVULSANT ACTION OF 5,7-DIPHENYL-1,3-DIAZADAMANTAN-6-OL (1757 I.S.)

¹ Laboratorio di Chimica Terapeutica, Istituto Superiore di Sanitá, Roma, Italy

The present paper describes the effects in spinal anesthetized cats of 5,7-diphenyl-1,3-diazadamantan-6-ol (1757 I.S.) on mono- and poly-synaptic reflexes, on spinal primary inhibition, and on the spontaneous and evoked discharge of single interneurones at the level of the spinal cord.

Augmentation of the polysynaptic reflexes was noticed after the i.v. administration of 0.1 to 0.4 mg/kg of the drug. The inhibition exerted by an afferent volley to the quadriceps nerve on the monosynaptic response due to stimulation of the biceps-semitendinosus nerves is blocked or diminished after the injection of subconvulsive doses of 1757 I.S.

Convulsive doses of the agent (0.4 mg/kg, i.v.) do not influence the spontaneous and evoked firing of the Renshaw cells.

These results, combined with earlier data obtained in this laboratory, strongly suggest that the principal action of 1757 I.S. is to abolish spinal inhibition, and indicate a close similarity between this agent and strychnine.