Adrenergic agonists suppress the proliferation of microglia through beta 2-adrenergic receptor.
The effects of several cyclic adenosine monophosphate (cAMP)-elevating agents on the proliferation of cultured rat microglia were investigated by immunocytochemical staining with an antibody against proliferating cell nuclear antigen (PCNA). Epinephrine, isoproterenol, forskolin and 8Br-cAMP suppressed the microglial proliferation. A beta2-selective agonist terbutaline but not a beta1-selective agonist dobutamine mimicked the effect of the above cAMP-elevating agents. Furthermore, a non-selective beta-receptor antagonist oxprenolol and a beta2-selective antagonist acebutalol, but not a beta1-selective antagonist butoxamine, counteracted the suppressive effects of the beta-agonists on microglial proliferation. These findings suggest that the beta-agonists suppress the proliferation of microglia by elevating intracellular cAMP level through an action on beta2-adrenergic receptor.
Fujita
H
H
Department of Anatomy, School of Medicine, Ehime University, Japan.
Tanaka
J
J
Maeda
N
N
Sakanaka
M
M
D015124:8-Bromo Cyclic Adenosine Monophosphate / Q000494:pharmacology; D058666:Adrenergic beta-2 Receptor Agonists; D000318:Adrenergic beta-Agonists / Q000494:pharmacology*; D000818:Animals; D000831:Animals, Newborn; D002455:Cell Division / Q000187:drug effects / Q000502:physiology; D002478:Cells, Cultured; D005576:Colforsin / Q000494:pharmacology; D006131:Growth Inhibitors / Q000494:pharmacology*; D017628:Microglia / Q000166:cytology* / Q000187:drug effects*; D009433:Neural Inhibition; D016548:Prosencephalon; D051381:Rats; D018343:Receptors, Adrenergic, beta-2 / Q000187:drug effects / Q000502:physiology
D058666:Adrenergic beta-2 Receptor Agonists; D000318:Adrenergic beta-Agonists; D006131:Growth Inhibitors; D018343:Receptors, Adrenergic, beta-2; D005576:Colforsin; D015124:8-Bromo Cyclic Adenosine Monophosphate