Fig. 9. Noradrenergic suppression of the swelling activated Cl^- current I_Cl,swell. Putative model of suppression of I_Cl,swell by norardrenaline and isoproterenol in microglial cells. The activation of β-adrenergic receptors stimulates a G-protein-adenylate cyclase (AC) system, which catalyses the formation of cAMP. Subsequently, cAMP activates cAMP-binding proteins including PKA and Epac which in turn are involved in the regulation of I_Cl,swell by yet unknown mechanisms.