ABSTRACT
PURPOSE: To investigate the role of adenosine A2A receptors on 6-OHDA-induced motor disorder in rat. METHODS: In order to induce experimental model of Parkinson's disease, 6-hydoxydopamine (8 μg/rat) was injected unilaterally into the SNc. After three weeks as a recovery period, 6-OHDA-induced bradykinesia and balance disturbances were assessed by using beam traversal test 10, 30 and 60 minutes after intraperitoneal injections of the drugs (caffeine, SCH58261). RESULTS: The results showed that 6-OHDA (8 μg/rat, Intra-SNc) induced motor disorders of Parkinson's disease and increased elapsed time in the beam test (p<0.001). Injection of caffeine (30 mg/kg, i.p.) and SCH58261 (2 mg/kg, i.p.) attenuated elapsed time on beam (p<0.01 and p<0.001). We showed that acute administration of caffeine and SCH 58261 can improve the 6-OHDA-induced bradykinesia and motor disturbance. CONCLUSION: Adenosine A2AR antagonists improve 6-OHDA-motor deficit and this effect seems to be mediated by the inhibition of A2A presynaptic receptors in substantia nigra pars compacta.
Subject(s)
Animals , Male , Parkinson Disease, Secondary/chemically induced , Caffeine/pharmacology , Oxidopamine/adverse effects , Purinergic P1 Receptor Antagonists/pharmacology , Adenosine A2 Receptor Antagonists/pharmacology , Time and Motion Studies , Rats, Wistar , Hypokinesia/chemically induced , Disease Models, Animal , Motor Disorders/chemically induced , Motor Activity/drug effectsABSTRACT
The effect of ethanolic extract of Coriandrum sativum L. seeds (100, 200 mg/kg) was studied on tacrine induced orofacial dyskinesia. Tacrine (2.5 mg/kg, i.p.) treated animals were observed for vacuous chewing movements (VCM), tongue protrusions (TP) and orofacial bursts (OB) for 1 h followed by observations for locomotor changes and cognitive dysfunction. Sub-chronic administration of Coriandrum sativum L. seed extract (E-CS) (100, 200 mg/kg, p.o., for 15 days significantly (P <0.05) decreased the tacrine induced VCM, TP and OB; and also significantly (P <0.05), increased locomotion and cognition compared to the tacrine treated group. Biochemical analysis revealed that tacrine administration significantly (P <0.05) decreased the levels of superoxide dismutase (SOD), Catalase (CAT), glutathione reductase (GSH) levels and also significantly (P <0.05) increased lipid peroxidation (LPO) as an index of oxidative stress, whereas sub-chronic administration of E-CS significantly (P <0.05) improved the antioxidant enzyme (i.e. SOD, CAT, and GSH) levels and also significantly (P <0.05) decreased lipid peroxidation (LPO). The results have demonstrated the protective role of ethanolic extract of Coriandrum sativum. L against tacrine induced orofacial dyskinesia.