Calcitonin gene-related peptide facilitates revascularization during hindlimb ischemia in mice.

Abstract

It is known that the neural system plays a fundamental role in neovascularization. A neuropeptide, calcitonin gene-related peptide (CGRP), is widely distributed in the central and peripheral neuronal systems. However, it remains to be elucidated the role of CGRP in angiogenesis during ischemia. The present study examined whether endogenous CGRP released from neuronal systems facilitates revascularization in response to ischemia using CGRP knockout mice (CGRP-/-). CGRP-/- or their wild-type littermates (CGRP+/+) were subjected to unilateral hindlimb ischemia. CGRP-/- exhibited impaired blood flow recovery from ischemia and decreased capillary density expressed in terms of the number of CD-31-positive cells in the ischemic tissues compared with CGRP+/+. In vivo microscopic studies showed that the functional capillary density in CGRP-/- was reduced. Hindlimb ischemia increased the expression of pro-CGRP mRNA and of CGRP protein in the lumbar dorsal root ganglia. Lack of CGRP decreased mRNA expression of growth factors, including CD31, vascular endothelial growth factor-A, basic fibroblast growth factor, and transforming growth factor-β, in the ischemic limb tissue. The application of CGRP enhanced the mRNA expression of CD31 and VEGF-A in human umbilical vein endothelial cells (HUVECs) and fibroblasts. Subcutaneous infusion of CGRP8-37, a CGRP antagonist, using miniosmotic pumps delayed angiogenesis and reduced the expression of proangiogenic growth factors during hindlimb ischemia. These results indicate that endogenous CGRP facilitates angiogenesis in response to ischemia. Targeting CGRP may provide a promising approach for controlling angiogenesis related to pathophysiological conditions.

• Authors: Toshiaki Mishima, Yoshiya Ito, Kanako Hosono, Yukio Tamura, Yasushi Uchida, Mitsuhiro Hirata, Tatsunori Suzsuki, Hideki Amano, Shintaro Kato, Yukiko Kurihara, Hiroki Kurihara, Izumi Hayashi, Masahiko Watanabe, Masataka Majima
• Journal: American journal of physiology. Heart and circulatory physiology (Am J Physiol Heart Circ Physiol) Vol. 300 Issue 2 Pg. H431-9 (Feb 2011) ISSN: 1522-1539 [Electronic] United States
• PMID: 21131474 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Angiogenic Proteins
• Calcitonin Gene-Related Peptide Receptor Antagonists
• Peptide Fragments
• calcitonin gene-related peptide (8-37)
• Calcitonin Gene-Related Peptide

Topics

• Angiogenic Proteins (biosynthesis)
• Animals
• Blood Pressure (genetics, physiology)
• Calcitonin Gene-Related Peptide (antagonists & inhibitors, genetics, pharmacology, physiology)
• Calcitonin Gene-Related Peptide Receptor Antagonists
• Cell Separation
• Ganglia, Spinal (cytology)
• Heart Rate (genetics, physiology)
• Hindlimb (blood supply)
• Humans
• Immunohistochemistry
• Ischemia (pathology)
• Laser-Doppler Flowmetry
• Male
• Mice
• Mice, Inbred C57BL
• Mice, Knockout
• Neovascularization, Physiologic (genetics, physiology)
• Neurons (physiology)
• Peptide Fragments (pharmacology)
• Regional Blood Flow (genetics, physiology)
• Reverse Transcriptase Polymerase Chain Reaction