[The predisposition to catatonic reactions, monoamine oxidase and the delta-sleep peptide in rats].

MAO B/MAO A rations and the influence of delta-sleep inducing peptide (DSIP) on the two forms of MAO and on the predisposition to different types of catatonic reactions were compared in rats of GC strain selected from Wistar for predisposition to catalepsy, and in wild rats. In GC rats, the MAO B/MAO A ratio was increased, as compared to Wistar, in the brain stem and hemispheres, whereas in wild rats predisposed to catatonia it was increased, as compared to normal wild rats, only in the hemispheres. In GC rats, this increase of the MAO B/MAO A ratio was due to a decrease of MAO A and increase of MAO B activity, while in wild catatonic rats only due to heightened MAO B activity. Administration of DSIP abolished the susceptibility to catatonic reactions and normalized the MAO B/MAO A ratio both in GC and in wild catatonic rats. There seems to be a partial similarity of physiological mechanisms of catatonic reactions in laboratory albino and in wild rats.