Use of electrofocusing for the analysis and purification of turkey erythrocytes β₁-adrenoceptors

We show that following one cycle of alprenolol affinity chromatography of turkey erythrocyte β₁,-adrenoceptors, electrofocusing on polyacrylamide gels in digitonin, followed by electroelution, results in complete receptor purification. The overall yield from the electrofocusing-electroelution step of turkey erythrocyte β-adrenoceptor is 75 ± 3 %. In addition, we are able to demonstrate that receptor-binding assays can be performed directly on the polyacrylamide gel, using ¹²⁵I-cyanopindolol. This method can be employed for minute quantities of receptor which is an advantage when one wishes to characterize rapidly the β-adrenoceptor in its native state from tissues that may be available only in limited amounts. We also report, for comparison, on the behavior of the turkey erythrocyte β₁,-adrenoceptor on immobiline polyacrylamide gels and the ability to purify only partially the receptor on these gels.