Catechol-O-methyltransferase activity and aminergic binding sites distribution in human peripheral blood lymphocyte subpopulations.
We have studied the binding of [3H]dihydroalprenolol, a beta-adrenergic ligand, and [3H]spiroperidol, a dopaminergic ligand, to human peripheral blood lymphocyte subpopulations. The catechol-O-methyltransferase activity on these different cells was also determined. On intact living cells, an unequal distribution of both beta-adrenergic and dopaminergic binding sites was found between B- and T-lymphocyte subpopulations. In each binding, T cells exhibited a lower number of binding sites than B cells. On particulate preparation, catechol-O-methyltransferase activity showed a similar distribution, but binding data with such material were quite different. Although it was not possible to detect dopaminergic binding sites on particulate preparation, T and B lymphocytes contained equivalent numbers of beta-adrenergic binding sites. Different explanations for these results are proposed.
D001402:B-Lymphocytes / Q000378:metabolism; D002394:Catechol O-Methyltransferase / Q000378:metabolism*; D004082:Dihydroalprenolol / Q000378:metabolism; D006801:Humans; D008214:Lymphocytes / Q000378:metabolism*; D011941:Receptors, Adrenergic / Q000032:analysis*; D011943:Receptors, Adrenergic, beta / Q000032:analysis*; D013134:Spiperone / Q000378:metabolism; D013601:T-Lymphocytes / Q000378:metabolism
D011941:Receptors, Adrenergic; D011943:Receptors, Adrenergic, beta; D013134:Spiperone; D004082:Dihydroalprenolol; D002394:Catechol O-Methyltransferase