These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Effect of thioridazine, clozapine and other antipsychotics on the kinetic state of tyrosine hydroxylase and on the turnover rate of dopamine in striatum and nucleus accumbens.
    Author: Zivkovic B, Guidotti A, Revuelta A, Costa E.
    Journal: J Pharmacol Exp Ther; 1975 Jul; 194(1):37-46. PubMed ID: 239221.
    Abstract:
    In rats, a single injection of antipsychotic drugs produced a transitory change in the kinetic state of tyrosine hydroxylase (TH) in striatum and nucleus accumbens. The affinity of TH for 2-amino-4-hydoxy-6,7-dimethyl-5,6,7,8-tetrahydropterine (DMPH4) and the Vmax with respect ot tyrosine were increased. The relative potencies of anti-psychotics to change the kinetics of TH in striatum and nucleus accumbens when injected into rats were measured in the presence of 0.4 mM DMPH4. The doses of methiothepin, pimozide and halopridol which increased the affinity for DMPH4 of striatal TH were lower than those required to produce a similar change in nucleus accumbens. In contrast, thioridazine and clozapine were more effective in nucleus accumbens than in striatum. Chlorpromazine was equally active in these two tissues. Haloperidol increased the turnover rate of dopamine in striatum with doses that are relatively smaller than those required in the nucleus accumbens. Clozapine was more active in increasing turnover rate of dopamine in nucleus accumbens; the activity of chlorpromazine in these two tissues was equal. These results suggest that antipsychotics with high incidence of extrapyramidal side effects affect the nigrostriatal dopaminergic pathway selectively.
    [Abstract] [Full Text] [Related] [New Search]