Treatment with PCPA (500 mg/kg) for 3 days significantly decreased body weight gain (Figure 1(a)) compared with controls. Treatment with PCPA for 3 days remarkably decreased expression of hypothalamic Tph2 compared with controls (25%) but did not affect the expression of hypothalamic 5-HT2A receptors in mice (Figure 1(b)). These findings demonstrate that despite the inhibition of Tph2, the treatment with PCPA does not affect expression of hypothalamic 5-HT2A receptors in mice.