The effect of medial prefrontal cortex electrical stimulation on passive avoidance memory in healthy and addict rats

Mehdipour, Shima; Alaei, Hojjat Allah; Pilehvariyan, Ali Asghar

The effect of medial prefrontal cortex electrical stimulation on passive avoidance memory in healthy and addict rats

Authors

¹ Department of Physiology, Faculty of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran

² Department of Basic Sciences, Isfahan Payame Noor University, Isfahan, Iran

Abstract

Background: The medial prefrontal cortex (mPFC) is a part of brain reward system involved in cognitive functions such as learning and memory. The mPFC receives strong dopaminergic innervations from ventral tegmental area (VTA) that comprises a portion of the mesolimbic dopaminergic system (MLDS), and sends glutamatergic projections to both the VTA and nucleus accumbens (NAc).
Materials and Methods: In this study, male Wister rats weighing 250-350 g were used. The effect of medial prefrontal cortex (mPFC) electrical stimulation with different current intensities (25, 50,100, and 150 µA) in healthy and addicted rats on passive avoidance memory was studied here.
Results: This study showed that 25 and 150 µA had no effect on improving avoidance memory in rats. Current intensities of 50 and 100 µA differ significantly with 25 and 150 µA. The PL of mPFC contributes to memory processing.
Conclusions: The electrical stimulations of prelimbic with 50 and 100 µA current intensities were improved avoidance memory in addicted rats while learning impairment is caused in healthy rats while the electrical stimulation with these used current intensities.

Keywords

References

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