Noradrenaline blocks potassium conductance in rat dentate granule cells in vitro.
The actions of noradrenaline and the beta-adrenergic agonist, isoproterenol, were studied on the dentate gyrus in hippocampal slices from rats using extra- and intracellular recording. These agents facilitated field EPSPs (excitatory postsynaptic potentials) and population spikes evoked by perforant path stimulation. Intracellular recording revealed an attenuation of the long lasting afterhyperpolarization (AHP) and the accommodation of cell discharge in response to depolarizing current injection. It is suggested that beta-receptor activation blocks a calcium-dependent potassium current.
D000818:Animals; D002118:Calcium / Q000502:physiology; D005071:Evoked Potentials / Q000187:drug effects; D006624:Hippocampus / Q000187:drug effects*; D066298:In Vitro Techniques; D007473:Ion Channels / Q000187:drug effects*; D007545:Isoproterenol / Q000494:pharmacology*; D009434:Neural Pathways / Q000187:drug effects; D009638:Norepinephrine / Q000494:pharmacology*; D011188:Potassium / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains; D011943:Receptors, Adrenergic, beta / Q000502:physiology; D009435:Synaptic Transmission / Q000187:drug effects
D007473:Ion Channels; D011943:Receptors, Adrenergic, beta; D007545:Isoproterenol; D011188:Potassium; D002118:Calcium; D009638:Norepinephrine