Plasma homovanillic acid as a predictor of response to neuroleptics
R. Davila, E. Manero, M. Zumarraga, I. Andia, J. W. Schweitzer and A. J. Friedhoff
Centro de Investigacion Neuroquimica, Osakidetza Gobierno Vasco, Zamudio, Spain.
Fourteen schizophrenic subjects were evaluated for degree of psychosis
before and after treatment with the antipsychotic drug haloperidol and for
plasma homovanillic acid concentration after four and 28 days of treatment.
A significant correlation was found between an increase in homovanillic
acid concentration on day 4 or a decrease from day 4 to day 28 and the
degree of improvement after four weeks of treatment. Thus, those patients
who had the greatest change in plasma homovanillic acid in response to
neuroleptic blockade showed the greatest improvement. These and other
observations have led us to propose that the central dopaminergic system,
through adaptive changes in activity, serves as a physiologic buffer system
protecting against destabilization of mental function from diverse biologic
or psychologic insults.