[Effect of pharmacological agents and coagulation of the n. raphe dorsalis on morphine effects]

The authors carried out studies on 96 female rats of Wistar strain and examined the influence of various pharmacological means and the coagulation of n. raphe dorsalis on cataleptic state, hyperthermia, and analgethic effect, induced by single administration of morphine. She found that LSD and preliminary treatment with parachlorphenylalanine caused enhancement of hyperthermic reaction to morphine. Acetyl-salicyliaccid had no effect on the hyperthermic reaction: dimenthydrinate and propranolol did alter it significantly, but cyproheptadine inhibited it. In respect to the cataleptic state, induced by morphine, she found that pharmacological means with various mechanism of action (parachlorphenylalatine, dimenhydrinate, cyproheptadine, propranolol and LSD) inhibited this states, but haloperidol enhanced it. She suggests that the hyperthermic reaction of morphine is due to, its action on serotoninergic neurones, regulating thermoregulation. She makes a guess that cataleptic state, induced by morphine, depends on the change in mediator interrelations (acethycholine, serotonine, dopamine). The lack of changes on the analhethic affect of morphine after coagulation of n. Raphe dorsalis, from which a part of accending serotoninergic pathways, supports the existing data in literature that both descending and accending serotoninergic pathways are of significance for analgethic action of morphine.