p-chlorophenylalanine attenuates the pituitary-adrenocortical response to 5-HT1A receptor agonists in mice

The i.p. injection of 8-hydroxy-2-(di-n-propylamino)tetralin (8-OH-DPAT) caused hypothermia and increased the concentrations of serum corticosterone and plasma ACTH in mice. The effects of 8-OH-DPAT at a dose of 2 mg/kg but not of 0.2 mg/kg on the hormone levels were attenuated by pretreatment with p-chlorophenylalanine (pCPA) which depleted brain 5-HT by about 70%; the hypothermic effect of 8-OH-DPAT was, however, not prevented. Similar results were obtained with another 5-HT1A agonist, 1-[3-(3,4-methylenedioxyphenoxy)propyl]-4-phenyl piperazine (BP-554).