The effect of neurohumoral drugs on the fixation of spinal reflexes and the incorporation of uridine into the spinal cord

✍ Scribed by Gene C. Palmer; G. R. Davenport; J. W. Ward

• Publisher: Springer
• Year: 1970
• Tongue: English
• Weight: 691 KB
• Volume: 17
• Category: Article
• ISSN: 0033-3158
• DOI: 10.1007/bf00402091

✦ Synopsis

Placement of a lesion in the anterior cerebellum of a newborn rat produces an asymmetrical flexion of the ipsilateral hind limb. If a midthoracic transection of the spinal cord is made before a median time of 38 rain has elpased the posturM asymmetry persists. Chamberlain et al. (1963) termed this critical period "fixation time" and postulated that neural activity during fixation may induce metabolic changes in appropriate spinal neurons. Ia the present experiments, neurohumoral drugs affecting cholinergie transmission (eserine high and low doses), adrenergic transmission (reserpine and amphetamine), and gamma amino butyric acid metabolism (methionine sulfoximine) altered fixation time. Injections of these drugs also altered the uptake of labeled uridine into the spinal cord segments during fixation. These results suggest that synaptic transmission is necessary for the processes that mediate fixation of the persisting postnral asymmetry. In addition to their primary actions on synaptic transmission these drugs may alter precursor pools for neural RNA synthesis.