[Effect of baclofen and muscimol on the evoked potentials of the tectum mesencephali in the carp in response to stimulation of the visual and somatosensory afferent inputs].

The perfusion of (+/-) 10(-5) M baclofen to the optic tectum of the carp greatly reduced evoked potential to the optic nerve stimulation and slightly inhibited evoked potential to the spinal cord stimulation. The perfusion of 10(-4) M muscimol reduced the former evoked potential as well as the latter one. The results permit supposing that tectal visual input is more sensitive to the presynaptic inhibitory influences through GABAB-receptors than the somatosensory afferent input.