THE PROPERTIES OF THE LONG-TERM POTENTIATION (LTP) IN THE SUPERIOR COLLICULUS

This chapter discusses long-term potentiation (LTP) formation in the superficial grey layer (SGL) of the superior colliculus (SC) in in vitro and in vivo. Some properties of the LTP in the SGL of the superior colliculus (SC) are mentioned. SC slices are prepared from the adult guinea pig and the rat. Tissue blocks of the SC are dissected out from the brain-stem and cut parasagitally into slices of between 400 and 500 μm thickness. The post-synaptic potential (PSP) was recorded from the SGL after stimulation of the optic layer (OL). Tetanic stimulation to the OL induced the long lasting increase of the amplitude of the PSP and elicited the LTP. In the hippocampus, it is reported that the N-Methyl-D-aspartate (NMDA) receptor, a subtype of the glutamate receptors, is involved in the induction of LTP. Protein kinase C inhibitors such as H-7, polymixine B and K-252a inhibit the maintenance of LTP. Application of GABA prevented the occurrence of LTP and bicuculline facilitated the formation of LTP. © 1993, Academic Press Inc.