Fig. 5
Reversal effect of the selective 5-HT1A receptor antagonist WAY 100635 (0.25 mg/kg, i.p.) on the inhibitory action of MA (5 mg/kg, i.p.) on DOI-induced (1 mg/kg, i.p.) HTR across different ages (20-, 30-, and 60-day old) in mice. Relative to the corresponding age-matched Vehicle + Vehicle + DOI pretreated control group, MA pretreatment (i.e. MA + Vehicle + DOI treatment group) significantly reduced the frequency of DOI-induced HTR in 20- 30- (all ****p < 0.0001) and 60-day old mice (*p = 0.0404). WAY 100635 by itself (i.e. in the Vehicle + WAY 100635+ DOI group) markedly attenuated the frequency of DOI-induced HTR in 20-day mice but did not affect the evoked behavior in 30- or 60-day old mice. Relative to the corresponding MA + Vehicle + DOI treatment control group at each age group, inclusion of the 5-HT1A receptor antagonist WAY 100635 (i.e. the MA + WAY 100635 + DOI treatment group) reversed the inhibitory effect of MA on DOI-induced HTR across all ages but significance was observed only during days 20 and 30. #p = 0.0239, ####p < 0.0001 vs. MA + Vehicle + DOI group; two-way ANOVA followed by Bonferroni's test. n = 6 − 10 in each group. Data are presented as means ± SEM.