Plasma prostaglandin E2 metabolite--measured as 11-deoxy-15-keto-13,14-dihydro-11 beta,16 xi-cyclo-PGE2--in twins with schizophrenic disorder.

Blood samples were obtained from 18 twin pairs, and the major prostaglandin E2 (PGE2) plasma metabolite 15-keto-13,14-dihydro-PGE2 was measured by RIA after its conversion to 11-deoxy-15-keto-13,14-dihydro-11 beta,16 xi-cyclo-PGE2. Significant positive correlations were found in all the twin pairs, in 11 pairs diagnosed as DSM-III schizophrenic disorder and schizoid/schizotypal personality disorder, and in the 5 nonschizophrenic pairs. These results indicate that synthesis of prostaglandins (PGs) is in part genetically determined. With regard to absolute PGE2 metabolite levels, the data did not support the hypothesis of increased PGE2 in schizophrenia. Thus, seven of eight schizophrenic probands had lower metabolite concentrations than their healthy twin siblings, and in one pair they were similar. Furthermore, schizophrenic probands and their healthy sibling controls, taken as a group, had lower PGE2 metabolite levels than the group comprised of affective disorder probands and their respective controls. These findings raise the possibility that a change in PGE2 may be associated with schizophrenic and also possibly with affective disorders.