光眼輪筋反射の神経薬理学的研究

Abstract

A neuropharmacological study was made on the photopalpebral reflex of rabbits and patients, and the results of the study are described hereunder:1. By recording the photopalpebral reflexes of rabbits evoked by a photic stimulation as average potential by means of MEDIAC, four negative responses (PN1, PN2, PN3 and PN4 components) were observed.2. In the photopalpebral reflex, a facilitatory effect was demonstrated similarly as in the blinking, when a simultaneous stimulation of 100 Hz was applied to the brain stem reticular formation, and that of 8 Hz was provided to the thalamus nucleus centrum medianum and nucleus ventralis anterior.3. In the observation of examining the action of such drugs as pentobarbital, chlorpromazine, myanesin, morphine, dardiazol and amphetamine to the photopalpebral reflex, a different result was obtained as compared with that of the blinking.4. In the examination where the optic nerve had been cut at the chiasma fasciculorum opticorum, only PN4 component out of other components disappeared after the cut. The result of the examination indicated that PN4 component is a phenomenon which appears through the central nervous system.5. According to the result of examining the action of drugs under the simultaneous stimulation of the brain stem reticular formation, it is clear that there exists in the central nervous system producing either a facilitatory or inhibitory effect against PN1, PN2 and PN3 components.6. While four negative responses are also observed in the photopalpebral reflex of human bodies similarly as in case of rabbits, it was observed that PN1 and PN2 components are inhibited in the case of a disturbance in the retinochoroid, and PN3 component is inhibited in the case of a disturbance in the optic nerve.It is concluded that from the aforementioned results, PN1 and PN2components have a relationship to the retinochoroid, PN3 component to the optic nerve, and PN4 component to the brain stem reticular formation.