Organization of olivocerebellar activity in the absence of excitatory glutamatergic input.

摘要: The olivocerebellar system has been proposed to function as a timing device for motor coordination in which inferior olivary neurons act coupled oscillators that spontaneously generate rhythmic and synchronous activity. However, the olive receives excitatory afferents, can also drive activity of these neurons. extent intrinsically neuronal not determined. To investigate this issue, multiple electrode recordings complex spike (CS) were obtained from 236 crus 2a Purkinje cells anesthetized rats. Intraolivary injections glutamate antagonists 6-cyano-7-nitroquinoxaline-2,3-dione or 1,2,3,4-tetrahydro-6-nitro-2,3-dioxo-benzo[f]quinoxaline-7-sulfonamide disodium made, resulting changes CS Loss evoked responses cortex stimulation perioral tactile was used measure efficacy block. Block glutamatergic input decreased average firing rate by ∼50% but did abolish spontaneous remaining significantly more than control. patterns synchrony similar those found control conditions (i.e., CSs primarily occurred among located within same ∼250-μm-wide rostrocaudally oriented cortical strip); however, normal banding pattern enhanced. These observed with vehicle injections. results suggest afferent disrupts oscillations support hypotheses are capable acting electrotonic coupling