Sulfinpyrazone increases the number of beta-adrenoceptors on intact human lymphocytes

Sulfinpyrazone increased the number of beta-adrenoceptors (+ 17-40%) on intact human lymphocytes at concentrations ranging from 10(-5) to 2 X 10(-4) M. It affected the Bmax (187 +/- 6 and 142 +/- 5 fmol mg-1 protein respectively with and without sulfinpyrazone, P less than 0.001) but did not influence KD (4.4 +/- 0.3 and 4.6 +/- 0.7 nM with and without the drug). This effect was observed on either washed or unwashed lymphocyte membrane preparations. These findings have several pharmacological and therapeutic implications.