ACTIVITY OF INTRASTRIATAL NIGRAL SUSPENSION IMPLANTS AS ASSESSED BY MEASUREMENTS OF DOPAMINE SYNTHESIS AND METABOLISM

Google Scholar
  • 1 January 1983
    • journal article
    • research article
    • Vol. 522, 19-28
Abstract
The activity of intrastriatal grafts of nigral cell suspensions was monitored biochemically, using radioenzymatic assay of dopamine [DA] its major acidic metabolite, DOPAC [3,4-dihydroxyphenylacetic acid] and dopa accumulation after dopa decarboxylase inhibition. Implants of 4-9 .mu.l of nigral cell suspension restored striatal DA levels by an average of 13-18%, with the highest individual values reaching .apprx. 50% of control. DOPAC was restored from .apprx. 5% in the lesioned controls to .apprx. 20% of normal in the grafted rats. The DOPAC:DA ratios and the dopa accumulation measures indicated that the grafted DA neurons were spontaneously active and that the transmitter turnover rate was on the average some 50-100% higher than the intact intrinsic nigrostriatal DA neurons. The intrastriatal nigral suspension grafts are capable of restoring dopaminergic neurotransmission in the previously denervated striatum.