METABOTROPIC RECEPTOR MODULATION OF NEURONAL EXCITABILITY

Metabotropic glutamate receptors are widely expressed throughout the mammalian nervous system. Through their actions on specific channels and membrane transporters, these receptors effect excitatory or inhibitory changes to neuronal excitability. Using whole-cell recordings from mouse brain stem slices, we characterize excitatory effects of Group I - mGluR on membrane potential and membrane currents in the locus coeruleus, a group of neurons in the brain stem responsible for a large share of noradrenergic innervation throughout the brain. We calibrate the strength of mGluR-I modulation by direct comparison with the inhibitory effects of morphine in these cells. Results indicate that mGluR-I activate a potent mechanism to increase the firing rate in locus coeruleus neurons mediated by the Na/K exchanger and L-type Ca2+ currents.
This work was supported by Conselho Nac. Des. Cient. Tecnologico (CNPq # 301798/2019-2)