Pharmacological studies on 3-[gamma-(p-fluorobenzoyl)propyl]-2,3,4,4a,5,6-hexahydro-1-(H)-pyrazino(1,2-a)quinoline hydrochloride (compound 69/183). Part IV: other CNS effects and acute toxicity.

ABSTRACT

3-[gamma-(p-Fluorobenzoyl)propyl]-2,3,4,4a,5,6-hexahydro-1-(H)-pyrazino(1,2-a)quinoline hydrochloride (centpyraquin), a potent antihypertensive and tranquillising agent, was tested for anticonvulsant, analgesic and anti-inflammatory activities in mice and for anti-emetic activity in dogs. It did not modify supramaximal electroshock seizures and failed to protect the animals against pentylenetetrazole and strychnine induced convulsions. It, however, produced some elevation in the threshold dose of strychnine. Tremorine induced tremors and salivation were not antagonised. The compound had weak analgesic activity as detected by antagonism to phenylquinone writhing and the hot plate test. It had no anti-inflammatory activity. Centpyraquin had strong anti-emetic activity against apomorphine as well as morphine. At high doses it produced fall out in the rota-rod test. The LD50 of centpyraquin in mice was 296 mg/kg i.p. and more than 1000 mg/kg p.o. and in rats it was 161 mg/kg i.p. and more than 800 mg/kg p.o. The observed CNS effects resemble those of other neuroleptics.