Phosphatidylinositol 4,5-Bisphosphate Induced Flunitrazepam Sensitive-GABA(A) Receptor Increase in Synaptosomes from Chick Forebrain.

CID, MP, SALVATIERRA NA, ARCE A

NEUROCHEMICAL RESEARCH

Springer Netherlands

Año: 2007 vol. 32 p. 1011 - 1015

0364-3190

The flunitrazepam sensitive-GABAA receptor density was increased by cytochalasins C and D at 37°C suggesting that microfilament depolymerization induces exposure to the radioligand of a GABAA receptor in synaptosomes (Pharm Biochem Behav 72 (2002) 497). Similarly, phosphatidylinositol-4,5-bisphosphate (1–5 ìM), but not a mixture of phospholipids, induced an increase of GABAA receptors in synaptosomes. Furthermore, N-ethyl maleimide, an inactivator of the sensitive fusion protein, which interacts with GABAA receptor, abolished the receptor increase induced by phosphatidylinositol-4,5-bisphosphate. Together, the results suggest that phosphatidylinositol-4,5-bisphosphate, acts via microfilament depolymerization increasing the binding of the radioligand to receptors possibly by modulation of their interaction with proteins involved in trafficking and docking mechanisms.