Central activation of thermogenesis by prostaglandins: Dependence on CRF

Central (intracerebroventricular) injections of PGE2, PGF(2α) caused dose dependent increases in oxygen consumption (V̇O2) and colonic temperature in conscious rats. The effects of combined injection of maximal doses of CRF and PGE2 were additive, whereas PGF(2α) and CRF were not. A CRF receptor antagonist, (α helical CRF 9-41, 25 μg icv) markedly inhibited the effects of PGF(2α) on V̇O2 and temperature, but did not affect the actions of PGE2. These data indicate that PGF(2α) and PGE2 stimulate thermogenesis by two different mechanisms, the former depending on CRF release. PGF(2α) may be involved in the thermogenic actions of interleukin-1β which is also a potent thermogenic agent acting via CRF.