Opiate ([3H]-naloxone) binding to hypothalamic and cerebral cortical slices of mouse brain

We have characterized the binding of [3H]-naloxone to thick (400 microns) slices of hypothalamus and cerebral cortex from mouse brain. Binding is reversible, saturable, stereospecific, thermolabile, readily displaceable by opiates and sensitive to phenoxybenzamine and phentolamine. Values for KD and Bmax are very close to published figures obtained in brain homogenates. Metabolic inhibitors (ouabain and azide) have no effect on specific binding. The assay is rapid, simple and involves minimal tissue preparation.