EFFECT OF CHOLECYSTOKININ-8 ON IN VITRO CULTURED RAT CORTICAL NEURONS AGAINST APOPTOSIS AND EXPRESSION OF NERVE GROWTH FACTOR

Objectives: To investigate the protective effect of cholecystokinin-8 (CCK-8) on in vitro cultured rat cortical neurons against apoptosis induced by glutamate, and study its effect on expression of nerve growth factor (NGF) in the neurons during apoptosis.

Methods: Cortical neurons were removed from newborn rat and cultivated in the medium, the models of damage induced by glutamate were established on cultured cortical neurons, and then treated with medium containing CCK-8, which concentration was 1×10–6mol/L, 1×10–7mol/L or 1×10–8mol/L. Apoptosis of cultured cortical neurons were observed by fluorescence microscope, The expression of NGF protein and mRNA were determined respectively by immunohistochemistry and in situ hybridization, and apoptosis of cortical neurons was measured by in situ end-labeling (TUNNEL).

Results: Compared to the model groups (which were pretreated with glutamate), the neurons apoptosis were significantly decreased in the neurons treated with CCK-8, which concentration was 1×10–6mol/L and 1×10–7mol/L, and at the same time NGF protein and mRNAexpression was up-regulated. The neurons apoptosis, NGF protein and mRNA expression in the neurons treated with 1×10–8mol/L CCK-8 were not different from the model group statistically.

Conclusion: Ectogenesis CCK-8 plays a protective role in apoptosis of the cortical neurons induced by glutamate, one of the protective mechanisms of CCK-8 is associated with the enhanced expression of NGF protein and mRNA.