Loss of zolpidem efficacy in the hippocampus of mice with the GABAA receptor gamma2 F77I point mutation. by Cope, D, Halbsguth, C, Karayannis, T, Wulff, P, Ferraguti, F, Hoeger, H, Leppä, E, Linden, A, Oberto, A, Ogris, W, Korpi, E, Sieghart, W, Somogyi, P, Wisden, W, Capogna, M