Intracranial self-stimulation regulates gene expression in rat hippocampus

Transcriptional profiling of rat hippocampus 4.5h post intracranial self-stimulation (ICSS) show that this treatment, which improves learning and memory processes in a variety of paradigms of implicit and explicit memory, regulates gene expression of genes related to cAMP-mediated signaling and regulation of synaptic plasticity, among others. Rats were implanted with a monopolar stainless steel electrode aimed at the lateral hypothalamus in the right hemisphere. Hippocampal gene expression was analyzed 4.5h post treatment comparing rats subjected to acute self-stimulation (2500 stimulation trains; ICSS group) with sham-operated rats (with electrode placement but placed in the ICSS without stimulation during 40 min.; Sham group). Two-condition experiment, ICSS and Sham. Every sample consisted of pooled hippocampi ipsilateral to the electrode from three rats. Slices between Bregma levels -2 and -4 were used for dissections of the hippocampi. Common reference design, comparing every condition versus a brain pooled tissue consisting of pooled hippocampal tissue ipsilateral to the electrode of sham-operated (n=3) and stimulated (n=3) rats. Biological replicates: 4 DBS and 4 sham. One replicate per array.