Role of Adenosine A2A receptors on 6-Hydroxydopmaine-induced catalepsy in rats

Subject Areas : Journal of Comparative Pathobiology

S.  Reyhani-Rad, ¹ (علوم آزمایشگاهی، واحد مرند، دانشگاه آزاد اسلامی، مرند، ایران)
J.  Mahmoudi, ² (مرکز تحقیقات علوم اعصاب، دانشگاه علوم پزشکی تبریز، ایران)

Received: 2014-12-27 Accepted : 2015-05-17 Published : 2015-07-23

Keywords: Caffeine, Catalepsy, 6-OHDA, Adenosine Receptor, Rat,

Abstract :

Parkinson’s disease (PD) is the second most prevalent neurodegenerative disease in ageingindividuals. This movement disorder caused by degeneration of dopaminergic neurons from thesubstantia nigra pars compacta (SNc). Caffeine consumption has been proposed to be associatedwith a reduced risk of Parkinson’s disease and caffeine in rodent models has protective effects.We have shown that caffeine and SCH58261 as A2A receptor antagonists improve motordysfunctions induced by 6-hydroxydopamine (animal model of Parkinson’s disease) in rats. Thepresent study extends these findings by investigating the role of A2A receptors on motor disorderinduced by unilateral infusion of 6-OH-dopamine into the substantia nigra, compact part (SNc)in rat. The experimental study was carried out on 72 male Wistar rats weighing between 180-200 g. Animals were divided into the groups contain 8 rats per group and were kept in standardcondition. 6-OHDA-induced catalepsy was assessed by using bar test. Caffeine (30 mg/kg i.p.)attenuated catalepsy on bar test in parkinsonian rats (P<0.001), whereas with dose of 10 mg/kgdid not produce significant effect (P>0.05). SCH58261 (2 mg/kg i.p) significantly improvedcatalepsy in bar test (P<0.001) in parkinsonian rat. These findings suggest that A2A receptors areinvolved in 6-OHDA-induced motor deficit like catalepsy. It seems that attenuating of catalepsymay caused by inhibition of A2A receptors.