بررسي اثرات داخل هيپوكامپي كربنوكسولون بر يادگيري فضايي در آزمون مازآبي موريس در رت

The effects of carbenoxolone, a gap junction channel blocker, on spatial learning in Morris water maze task in rats

High frequency oscillations (ripples) are proposed to involve in memory consolidation. Ripple oscillations persist in the absence of chemical synaptic transmission and inhibitors of gap junctions were shown to block high frequency oscillations in hippocampal slices. In this study, we investigated the effects of carbenoxolone, as a gap junction blocker, on spatial learning in the rat. Cognitive ʹperformance was assessed using Morris water maze (MWM). Adult male rats were bilaterally cannulated into the CAl region of their hippocarnpus. Carbenoxolone (1.23, 2.46, 4.92 (mio)g/side), scopolamine (3(mio)g/side) and saline were injected through the cannulas before training for 4 consecutive trials and one probe trial that was conducted 24 h after the training trials with the platform removed. The results showed that carbenoxolone could significantly reduced percent of time spent, distance traveled and quadrant entry in Q2 compared to control group and failed to use a selective search strategy during probe trial in which the platform was removed. The results of the present study suggest that carbenoxolone as a gap junction channels blocker can-decelerate learning performances of rats in a spatial memory task such as the MWM that requires the integrity of hippocampus.