Buffer effects on high affinity [3H]-prazosin binding in brain and spinal cord.

[3H]-Prazosin binding was characterized in cortical and spinal membranes from Fischer 344N and Sprague-Dawley rats. Estimates of Bmax and Kd values were comparable with earlier studies of these regions in the central nervous system (CNS). However, the Kd obtained using Tris buffer system was greater than when HEPES or phosphate buffer was used. These data indicate that high affinity [3H]-prazosin binding in the homogenates of tissue from the CNS is affected critically by buffer selection.