The Effects of Sodium Hydrosulfide on Motor Learning in a Rat Model of Parkinson’s Disease

 Hydrogen Sulfide (H2S), a novel endogenous gasotransmitter, plays an important role in neuromodulation and memory performance and also protects neurons against neurotoxin-induced neurodegeneration.  This study aimed to investigate the potential neuroprotective effects of Sodium Hydrosulfide (NaHS), on motor learning in a unilateral 6-Hydroxydopamine (6-OHDA) rat model of Parkinson’s Disease.  Male Wistar rats were subjected to unilateral injection of 6-OHDA (15 μg) into the Medial Forebrain Bundle (MFB) and then treated with NaHS for 25 days. Animals were divided into control, sham, sham plus NaHS, Parkinson (6-OHDA), Parkinson plus vehicle (saline), and Parkinson plus NaHS (2.8 and 5.6 mg/kg, IP) groups, (N=8). One-way ANOVA followed by turkey’s test was applied for statistical analyses of the data.  The riding time in fixed and accelerating speed rotarod were significantly decreased in Parkinson rats (6-OHDA group) compared to controls in all training days (P<0.001). Treatment with NaHS (2.8 and 5.6 mg/kg/d) reversed these decreases in a dose-dependent manner, so no significant differences were found in these parameters between the control and Parkinson plus NaHS groups during the accelerating speed rotarod test.  In the Parkinson rats, NaHS administration enhanced and improved the endurance time in the rotarod test. These results demonstrate that NaHS treatment enhances rat motor balance and coordination and suggest treatment with NaHS attenuates motor impairments in the Parkinson rats.