Administration of antisense DNA for ghrelin causes an antidepressant and anxiolytic response in rats

Abstract Rationale Ghrelin is a peptide of 28 amino acids found in mammals that increases the release of growth hormone, food intake, and body weight. Objectives We investigated the relationship between ghrelin and the states of anxiety and depression by giving rats either antisense DNA for ghrelin, scrambled DNA or vehicle into the lateral ventricle of rats. Results In forced swimming tests, rats that received antisense DNA decreased the length of time that they were immobile in the water. Ghrelin antisense oligonucleotides produced an anxiolytic-like effects in the elevated plus maze test, black and white test, or conditioned fear tests. Treatment with antisense DNA for ghrelin significantly decreased rat body weight. No significant effect on general locomotor activity was seen. Conclusions These results suggest that administration of antisense DNA for ghrelin causes an antidepressant and anxiolytic response in rats.