Diazepam modification of evoked and spontaneous lateral geniculate activity.

The effects of diazepam on evoked and spontaneous activity of dorsal lateral geniculate nucleus (dLGN) principal (P) and inhibtory (I) cells were examined in rats. In the majority of P cells tested both spontaneous and evoked activity were suppressed following diazepam treatment with these effects being altered little by a pentylenetetrazol (Metrazol) challenge. In two P cells, which were offresponding to photic pulse stimulation, evoked and spontaneous activity was enhanced by diazepam but again these effects were altered little by the Metrazol challenge. I cell spontaneous activity was suppressed by diazepam and augmented by the Metrazol challenge; however, post-stimulus activity was relatively unaffected by either treatment. These results were discussed in terms of support for a functional re-evaluation of the rat dLGN.