Identification of strychnine binding sites in the rat retina

[3H]Strychnine specifically binds to membrane fractions isolated from rat retinae. The binding is saturable, with an apparent dissociation constant, KD, of 14.3 x 10(-9) M and 205 fmol bound/mg protein. Specific binding is time-dependent and proportional to protein concentration. Glycine and taurine are equally potent inhibitors of [3H]strychnine binding (Ki = 4 x 10(-5) M); no other amino acids endogenously present in the retina inhibited [3H]strychnine binding.