Adrenomedullin administration alters vascular endothelial growth factor levels in rats in cold stress

Background: Many endogenous peptides play important regulatory roles in angiogenesis by modulating endothelial cell behavior. Adrenomedullin (AdM) is one of such factors. Angiogenesis and vascular endothelial growth factor (VEGF) are indistinguishable. Exposure to cold environment stimulates capillary angiogenesis. Objectives: Examine the effect of the bioactive peptide AdM on VEGF levels in rat liver, lung, brain, and heart tissues after cold stress treatment. Methods: Male wistar rats were divided into four groups as control, AdM treatment, cold stress and AdM+cold stress treated groups. In AdM-treated group, animals received intraperitoneal injection of AdM (2000 ng/kg body weight) once a day during a week. For the cold stress exposure, the rats were kept in separate cages at 10 degrees C for a week. Results: The administration of AdM increased VEGF levels in all tissues in cold exposed rats. Conclusion: AdM may be a major regulatory factor in angiogenesis by modulating VEGF levels that is closely associated with cold exposure-related metabolic stimulation.