Effect of methylglucamine orotate on intracranial self-stimulation.

The effect of the memory improving substance methylglucamine orotate (MGO) on intracranial self-stimulation was investigated in rats. Self-stimulation (0.2 mn square pulses; 100 Hz frequency; 400 mn chain; 100-300 micro A current) was performed using electrodes in the lateral hypothalamus. MGO was administered intraperitoneally in doses of 112.5 mg/kg and 225 mg/kg or intraventricularly in a dose of 225 micrograms per rat. In chronic experiments, daily intraperitoneal injections of 225 mg/kg MGO were given during 10 days. The results show that intracranial self-stimulation is scarcely influenced by a single injection of retention improving MGO doses, but increased significantly by repeated MGO application.