Demonstration of melatonin-binding sites in cyclohexylamine-formaldehyde-fixed brain tissues

This study shows for the first time that perfusion of rat or hamster brain with a cyclohexylamine-paraformaldehyde mixture makes possible the observation by autoradiography of melatonin binding sites in structurally well-preserved fixed tissues. This result is a first step in the identification of melatonin-receptor-containing cell types by cytoautoradiography.