Impacts of low-protein diet on the hippocampal CA1 neurons and learning deficits in rats

Introduction: Proteins are the essential part of all organism cells. Nutrition plays the most important role in the structure and function of the brain. CA1 region belongs to hippocampus and plays a vital role in converting short-term to long-term memory. This study was designed to assess the effects of low-protein diet on hippocampal region CA1 and learning deficit in rats. Materials and Methods: In this study, 30 male rats were randomly assigned to two groups: control group and low-protein diet group (8% protein). Animals in a low-protein diet group have eaten food with low protein daily for 10 months. Body weight was measured. Transcardiac perfusion method was applied to tissue fixation. Passive avoidance learning of animals was examined by the shuttle-box apparatus technique. The number of dendritic spines was investigated by the Golgi staining technique. Furthermore, Cresyl violet staining method was used to determine the number of neurons in the hippocampal region CA1. Results: The passive avoidance learning of the low-protein diet rats was reduced significantly compared to the control ones (P < 0.001). Low-protein diet decreased the body weight, number of neuronal dendritic spines and neurons compared to the control group (P < 0.001). Conclusion: It seems that administration of low-protein diet had harmful effects of structure and function of hippocampal region CA1 in rats.