| First Author | Jian K | Year | 2010 |
| Journal | Brain Res | Volume | 1354 |
| Pages | 47-63 | PubMed ID | 20692242 |
| Mgi Jnum | J:165150 | Mgi Id | MGI:4836329 |
| Doi | 10.1016/j.brainres.2010.07.104 | Citation | Jian K, et al. (2010) Metabotropic glutamate receptors 1 and 5 differentially regulate bulbar dopaminergic cell function. Brain Res 1354:47-63 |
| abstractText | Effects of activation of metabotropic glutamatergic receptors (mGluR) were investigated in mouse dopaminergic olfactory bulb neurons. After blockage of ionotropic receptors, focal application of glutamate or of group I/II mGluR agonist t-ACPD resulted in a depolarization, paralleled by an inward current in voltage-clamp conditions. The Group I agonist DHPG induced a depolarization, which could be largely blocked by mGluR1 antagonists. The DHPG action i) was prevented by buffering intracellular Ca(2+) with BAPTA and by a phospholipase C inhibitor; ii) was not affected by the block of Ca(2+) entry, and iii) was blocked by inhibitors of the Na(+)/Ca(2+) exchanger. These observations were interpreted as a mGluR1-mediated intracellular Ca(2+) release, followed by the activation of an electrogenic Na(+)/Ca(2+) exchanger. The mGluR5 agonist CHPG induced a hyperpolarization of membrane potential, resulting in a decrease of the spontaneous firing frequency. CHPG induced i) a decrease in membrane resistance; ii) an increase in the action potential repolarization rate, and iii) an increase in the amplitude of the afterhyperpolarization. This was interpreted as a mGluR5-mediated opening of a K(+) conductance. These data suggest that mGluR1 and mGluR5 play different and non-overlapping roles in the regulation of the excitability of bulbar dopaminergic neurons. |
