Maturational age affects pirenperone dose-response pattern

The effects of the 5-HT2 antagonist pirenperone on temperature preference were observed 1 hr after injection in mice aged 3, 5 and 7 days and at doses of 0.16, 0.48 and 1.6 mg/kg body weight. Although all 3 doses produced significant decreases in preferred temperature at 3 days, only the highest dose had significant effects at ages 5 and 7 days. Analysis of the data suggests that the dose-response relationship depends on age in a way that would be consistent with a shift in the dose-response curve with increasing age.