Light stimulates the rapid formation of inositol trisphosphate in squid retinas.

摘要: To test the hypothesis that inositol trisphosphate (InsP3) mediates adaptation and excitation in invertebrate photoreceptors, we measured its formation on a rapid time scale squid retinas. For squid, adaption occurs within 0.1 1-2 s respectively. We could detect an elevation InsP3 200 ms of bright flash. This increase is about 240% over dark basal levels maintained for at least 2 min after The probably which are only neurons Analysis by h.p.l.c. indicates light-regulated isomer Ins(1,4,5)P3, formed hydrolysis phosphatidylinositol bisphosphate (PtdInsP2).