Effects Of Calcitonin Gene-related Peptide(CGRP) On Migration Of Epidermal Stem Cells In Wound Healing

People study stem cells from the1960s, we have made a breakthrough in the study of stem cell, which was accompanied with the development of biological experiment technology, Recently, people can abstract,identify,amplify and cultivate epidermis stem cells(ESCs),The study of ESCs can help us to comprehend skin recovery and cutaneous carcinogenesis mechanisms. We have investigated ESCs for 20 yeas. although on experiment phase, it have shown very satisfactory outlook on clinical application.The marker of epidermis stem cells: So far,no literature report the specific marker of epidermis stem cells。Now,academic circles approval BrdU,β1 integrin and K19,because ESCs appear morphologically unmature,have strong self-renewal capability and expressβ1 integrin K19.So,we adoptβ1 integrin,K19 and BrdU(a nuclei marker , was used as the trace marker to observe wound healing) in the experiment in order to conclude more exactly.Neuropeptide:we have certified epidermis stem cells(ESCs) distribute the same as nervus sensorialis do and substance P(SP) can not only obviously promote the wound healing and shorten the healing duration , but also induce aggregation of ESC towards wound border or migration of ESC to granulation tissues.Now ,there is no report that Calcitonin gene-related peptide(CGRP) have similar effect.Objective:To study the effects of calcitonin gene-related peptide(CGRP) on migration of epidermal stem cells(ESC) in wound healing.To certified the finding of substance P(SP) before,and compare effect of CGRP with that of SP in wound healing.Methods:Inject BrdU(a nuclei marker, was used as the trace marker to observe wound healing)into 60 pedo-rats′abdominal cavity,after them was bred for 60 days. The rats with full thickness skin injury on back were randomly divided into four groups, ie. CGRP group and SP group (injected with CGRP and SP group at the day of injury, once per day), capsaicin group (subcutaneously injected with capsaicin before injury)and control group. Observe wound healing and migration of ESC based on slow cell cycling and label restraining of ESC.Results:Among four groups,the wound healing in the CGRP group and SP group were the fastest while that in the capsaicin group the slowest;the proportion of BrdU positive cells in the CGRP group and SP group ranked the highest while that in the capsaicin group the least. BrdU positive cells appeared in the granulation tissues in the CGRP group and SP group rather than in the other two groups.Conclusion:CGRP can not only obviously promote the wound healing and shorten the healing duration , but also induce aggregation of ESC towards wound border or migration of ESC to granulation tissues.