Muscarinic receptors binding in retinal pigment epithelium during rat development

摘要

3HQuinuclidinyl benzylate (3H-QNB) specific binding of the developing rat retinal pigment epithelium (RPE) and neural retina has been examined. The binding of3H-QNB to RPE was saturable and displaced by the antagonist pirenzepine. Scatchard analysis of3H-QNB binding showed two high affinity sites to RPE, with KB=2.6nM and 45 nM. Specific3H-QNB binding membranes from neural retina exhibited a characteristic developmental profile. RPE showed a high density of3H-QNB binding sites through all developmental periods studied. The major onset of binding sites is at the time of RPE differentiation. Our data open the possibility of muscarinic receptors being involved in differentiation and/or proliferation of RPE.