neuropeptide-y and Brain-Injury--Chronic

We have analyzed the effects of a small cortical infarct which is known to induce dramatic changes in gene expression in the entire cerebral cortex, on the gene expression in the striatum, a target structure of cortical neurons. Striatal glutamic acid decarboxylase (GAD67) and enkephalin expressions were increased in the striatum ipsilateral to the lesion. Conversely, neuropeptide Y- and somatostatin-like immunoreactivity were decreased in the ipsilateral striatum and this decrease was only related to a decrease in the labeling of processes with no changes in the number of labeled neurons. A minimal cortical lesion may therefore induce changes in gene expression in a subcortical structure through hyperactivity of glutamatergic synaptic inputs. One should therefore remember these extensive and long-lasting effects when surgical manipulations are performed on rat brain for stereotaxic surgery and placement of electrodes or probes.

Topics: Animals; Brain Injury, Chronic; Cerebral Cortex; Enkephalins; Glutamate Decarboxylase; Immunohistochemistry; In Situ Hybridization; Male; Neostriatum; Neuropeptide Y; Neuropeptides; Oligonucleotide Probes; Protein Precursors; Radiography; Rats; Rats, Wistar; RNA, Messenger; Somatostatin