β-adrenergic receptors on splenic lymphocytes from axotomized mice

Abstract

Adrenergic receptors are present on lymphocytes but the extent to which their activation modulates lymphocyte function remains unclear. We studied β-adrenergic receptors on mouse spleen lymphocytes using the antagonist 3H-dihydroalprenol ( 3H-DHA) as a specific ligand. We report a significant increase in β-receptor density in spleen lymphocytes from mice treated with 6-hydroxydopamine (6-OHDA) to destroy peripheral sympathetic nerve endings (axotomy). Mouse spleen lymphocytes were separated into T and B subpopulations on nylon wool columns or by panning. B cells from both control and axotomized mice were found to bear twice as many β-receptors as T lymphocytes. Finally, using flow cytometry to identify cells labeled with goat anti-mouse immunoglobulin (lg), axotomized mouse spleen lymphocyte populations were shown to contain 25% fewer B cells than controls. This work demonstrates differences in β-adrenergic receptor density of functionally distinct populations of lymphocytes. Furthermore, we show adaptive changes in receptor density on T and B lymphocytes following sympathetic denervation. Both of these observations serve to link the immune and sympathetic nervous system in a regulatory network.