抄録
Phospholipase C (PLC)-related inactive protein-1 (PRIP-1) is known as an inositol 1,4,5-triphosphate [Ins(1,4,5)P3] binding protein, which plays an important role in GABAA receptor trafficking and function. However, little is known about its role in the functional properties of GABA inhibitory postsynaptic currents (IPSCs) in the barrel cortex. Therefore, we studied the role of PRIP-1/2 in the modulation of GABA IPSCs in layer II/III pyramidal neurons of barrel cortex using PRIP-1 and -2 knockout (PRIP-DKO) mice. The mean frequency, amplitude and 10-90% rise time for GABAergic miniature IPSCs showed no difference between wild-type and PRIP-DKO mice. However, the half decay time in PRIP-DKO mice was significantly shorter than that in wild-type mice. Furthermore, the maximum amplitude of GABA IPSCs induced by puff application (2 sec duration) of 200 μM GABA in PRIP-DKO mice was significantly smaller than that in wild-type mice at high pressures, and the 10-90% rise time and half decay time of GABA IPSCs in PRIP-DKO mice were significantly shorter than those in wild-type mice. Interestingly, an after-response was observed at the offset of puff application only in PRIP-DKO mice. Taken together, these results suggest that PRIP-1/2 may play an essential role in desensitization and resensitization in GABAA receptors. [J Physiol Sci. 2007;57 Suppl:S150]
