Changes in CCK mRNA in hippocampal neurones following fimbria fornix transection.

Preprocholecystokinin (CCK) mRNA expression was measured in a subset of hippocampal interneurones after transection of afferent septohippocampal fibres in the fimbria fornix. Two weeks after the lesions were made, CCK mRNA levels were significantly lower in these neurones on the side ipsilateral to the lesion compared with equivalent neurones on the unlesioned side. These findings suggest that axotomizing lesions can change gene expression in denervated target cells, and that CCK mRNA levels in hippocampal interneurones may be modulated by afferent septohippocampal input.