Abstract:

Objective   To investigate the effects of ABT-724， a selective dopamine D4 receptor， on attentional set-shifting behaviors in spontaneously hypertensive rats (SHR), a rat model of attention-deficit hyperactivity disorder (ADHD). Methods   According to the dose of ABT-724 (intraperitoneal injection, 0.04, 0.16 and 0.64mg/kg), SHR rats were divided into three (low, medium and high dose) groups. SHR rats intervened with methylphenidate (25mg/kg) or saline and Wistar-Kyoto (WKY) rats intervened with saline were all taken as control groups, and they were named as methylphenidate group, SHR saline group and WKY saline group, respectively. The effects of ABT-724 on attentional set-shifting behaviors in SHR rats were observed. Results   Compared with SHR saline group, the trials and errors to reach criterion were all reduced in low, medium and high dose group (P< 0.01). Compared with methylphenidate group, there was no obvious difference in trials and errors to reach criterion for all the three dose groups (P>0.05).  According to the error types, low, medium and high dose groups showed less perseverative and regressive errors than SHR saline group (P<0.01), but showed no obvious difference in never-reinforced error (P>0.05). Compared with methylphenidate group, there was no significant change in error types for all the three doses groups (P>0.05). Conclusion    ABT-724 can improve attentional set-shifting behaviors in SHR rats as methylphenidate.

Key words: Attention-deficit hyperactivity disorder; Dopamine D4 receptor; ABT-724; Spontaneously hypertensive rat; Attentional set-shifting