Effects of subcutaneous carbon dioxide on calcitonin gene related peptide and substance P secretion in rat skin

ABSTRACT

To investigate the subcutaneous injection of carbon dioxide (CO2) on neuropeptides Calcitonin Gene-Related Peptide (CGRP) and Substance P (SP) secretion in rat skin. Fifty-six Wistar-EPM rats were distributed in two groups one for CGRP analysis, the other for SP analysis. Each group was subdivided into four subgroups control (Cont), control with needle (ContNd), CO2 injection (CO2Inj) and atmospheric air injection (AirInj) - with seven animals each. Sample analyses of partial skin were conducted by Western Blotting (WB). RESULTS: In SP group, there was a decrease in the amount of neuropeptides in subgroups CO2Inj and AirInj. Similarly, in CGRP group, there was a decrease in the amount of pro-CGRP neuropeptides (15 kDa) in subgroups CO2Inj and AirInj; Nevertheless, there was no decrease in the amount of CGRP (5 kDa) in any subgroups. Subcutaneous injection of CO2 and atmospheric air decreased the amount of Substance P and pro-Calcitonin Gene-Related Peptide (15 kDa) neuropeptides in rat skin.