Abstract: | Spinal motoneurons were activated orthodromically or antidromically with preservation of inhibitory synaptic influences (experiments on healthy rats) and after blocking these influences by tetanus toxin (experiments on rats with local tetanus). The RNA content in the cytoplasm of the -motoneurons was measured by cytospectrophotometry in UV light. The results showed no quantitative changes in the RNA of the motoneurons during action potential generation. Meanwhile the content of neuronal RNA depends on the character of synaptic influences. The RNA content in the motoneurons rises in response to excitatory and falls in response to inhibitory synaptic action. The possible mechanisms of the observed cytochemical changes in the RNA content during synaptic excitation and inhibition of motoneurons are discussed.Institute of Higher Nervous Activity and Neurophysiology, Academy of Sciences of the USSR. Institute of Normal and Pathological Physiology, Academy of Medical Sciences of the USSR, Moscow. Translated from Neirofiziologiya, Vol. 4, No. 4, pp. 418–422, July–August, 1972. |