Actions of desoxynupharidine hydrochloride in the central nervous system of experimental animals (I)

The effects of desoxynupharidine hydrochloride (DN) as the extractive component of the Nuphar japonicum DC on the central nervous system were studied. In the acute cats, DN (1-3 mg/kg, i.v.) produced 8-10 Hz waves in the hypothalamus lateralis and amygdala, and the hippocampal arousal wave gave way to the irregular high amplitude slow waves. In the midbrain reticular formation, nucl. reticularis and cortex, 12-13 Hz waves and high amplitude slow waves increased. A sleep-like pattern with spindle burst-like waves formed the general pattern of all EEGs. These spontaneous EEG activities were significantly inhibited by epinephrine hydrochloride and were potentiated by tolazoline hydrochloride and dibenamine hydrochloride etc. The above EEG changes were obtained even in the spinal cats. DN depressed the EEG arousal response produced by high frequency stimulation of the sciatic nerve and increased the threshold of stimulation. In the chronic cats, DN (1 mg/kg, i.v.) produced spindle burst-like waves of 12-14 Hz in the cortex and sedation concomitantly. These findings suggest that DN has an inhibitory effect on the central nervous system and that adrenergic neurons are probably involved.