An Overview of Non-Neural Sources of Calcitonin Gene-Related Peptide

Calcitonin gene-related peptide (CGRP) is extensively distributed throughout the central and peripheral nervous systems and has been shown to be a 37 amino acid multifunctional neuropeptide involved in a wide range of physiological and pathological processes. Recently, there is increasing evidence suggesting that CGRP also exists in non-nerve cells, such as epithelial cells, endothelial cells, endothelial progenitor cells (EPCs), T lymphocytes, B lymphocytes, peripheral blood mononuclear cells (PBMCs), and adipocytes. The existence of CGRP in non-neural tissue is of great importance to the regulation of multiple physiological and pathological processes via different pathways, especially through an autocrine/paracrine mode. This review integrates evidence from recent developments and aims to provide novel insights into non-neural sources of CGRP and its effects on physiological and pathological processes.