CALCITONIN-GENE-RELATED PEPTIDE INCREASES MICROCIRCULATION AFTER MECHANICALLY INDUCED ISCHEMIA IN AN EXPERIMENTAL ISLAND FLAP

Vasoconstriction, as a result of mechanical manipulation of blood vess els during microsurgery, may produce a decrease in blood supply and en danger flap viability, A study was undertaken to determine the effects of the topical vasodilator calcitonin gene-related peptide on the mic rocirculation of flaps after mechanically induced ischemia, A neurovas cular island flap based on the superficial epigastric vessels was rais ed in 42 rats, Blood cell flux in the flap was recorded continuously w ith a laser Doppler flux meter, The feeding artery was pinched to indu ce vasospasm, and different concentrations of calcitonin gene-related peptide (10(-7), 10(-8), 10(-9), 10(-10) mol) or a control of sodium c hloride 0.9% was applied topically to relieve the ischemia. Results sh owed that calcitonin gene-related peptide at a concentration of 10(-7) mol significantly shortened the time to reach 50% of the original blo od cell flux values (270 +/- 123 seconds) and significantly increased the number of flaps in which the blood cell flux values were restored to prestress levels within 30 minutes, The data support the conclusion that, in this model, topical calcitonin gene-related peptide at the c oncentration of 10(-7) mol was effective in promoting recovery of the microcirculation after mechanically induced ischemia, without the adve rse effects associated with other commonly used vasodilators.