Mechanism of chlorpromazine action on plasma glucose and cyclic AMP levels.

The s.c. administration of chlorpromazine (CPZ) caused an elevation of plasma glucose and cyclic AMP levels in fed intact mice, but not in fed adrenalectomized mice. The pretreatment with reserpine partially blocked the elevation of plasma glucose and cyclic AMP. The pretreatment with 6-hydroxydopamine or alpha-methyl-p-tyrosine failed to inhibit the increase of plasma glucose and cyclic AMP induced by CPZ. These findings suggest that CPZ acts on the central nervous system and increases plasma glucose and cyclic AMP through epinephrine release from the adrenal medulla. The elevations of plasma glucose and cyclic AMP induced by epinephrine were enhanced by CPZ. CPZ increased plasma glucose and cyclic AMP significantly at high room temperatures (28 and 33 degrees C) at which CPZ did not decrease body temperature. The mechanism of CPZ action is discussed in relation to the increase in the plasma glucose and cyclic AMP levels.