Studies on the effects of some biogenic amines on plasma fibrinogen level of rats and rabbits

Abstract

Intramuscular administration of iproniazid caused significant elevation of plasma fibrinogen in rats and rabbits. The elevation may be due to accumulation of monoamines, as the drug inhibited plasma monoamine oxidase quite strongly. This possibility was further supported by the fact that the direct administration of 5HT also elevated the plasma fibrinogen level by about 50 per cent. The effect of 5HT was more pronounced (about 75 per cent) when rabbits were pretreated with reserpine. The above observation has also been confirmed by reserpine-treated rats where different biogenic amines like 5HT, tryptamine, tyramine and epinephrine at low doses elevated plasma fibrinogen level. These biogenic monoamines possibly mediated their action through synthesis of protein since the increase of plasma fibrinogen level after 5HT administration was prevented by pretreatment of animals with actinomycin D or cyclohexamide.