Prostaglandin D2 sustains the pyrogenic effect of prostaglandin E2

Prostaglandin D2 (PGD2) is involved in a variety of physiological and pathophysiological processes, but its role in fever is poorly understood. Here we investigated the effects of central PGD2 administration on body temperature and prostaglandin levels in the cerebrospinal fluid (CSF) of rats. Administration of PGD2 into the cisterna magna (i.c.m) evoked a delayed fever response that was paralleled by increased levels of prostaglandin E2 (PGE2) in the CSF. The elevated PGE2 levels were not caused by an increased expression of cyclooxygenase 2 or microsomal prostaglandin E synthase-1 in the hypothalamus. Interestingly, i.c.m. pretreatment of animals with PGD2 considerably sustained the pyrogenic effects of i.c.m. administered PGE2. These data indicate that PGD2 might control the availability of PGE2 in the CSF and suggest that centrally produced PGD2 may play a role in the maintenance of fever.