MAGNESIUM-SULFATE INFUSION DECREASES CIRCULATING CALCITONIN-GENE-RELATED PEPTIDE (CGRP) IN WOMEN WITH PRIMARY RAYNAUDS-PHENOMENON

The effects of two different vasodilating agents (MgSO4 infusion and t he calcium antagonist nifedipine) on circulating levels of calcitonin gene-related peptide (CGRP) were studied in 12 women with pronounced p rimary Raynaud's phenomenon (PRP) and in 12 healthy females. There wer e no significant differences with regard to basal levels of circulatin g CGRP between women with PRP and the control group; median 15.5 (rang e 10-48) vs. 14 (range 10-69) pmol l(-1) respectively. However, treatm ent with MgSO4 infusion significantly decreased circulating CGRP in wo men with PRP only from median 15.5 (range 10-48) to 10 (range 10-110) pmol l(-1)) (P<0.05). On the other hand 14 days of treatment with nife dipine did not affect circulating CGRP in either of the investigated g roups. Erythrocyte magnesium (ery-Mg) levels increased significantly a fter MgSO4 infusion in women with PRP (2.43+/-0.13 vs. 2.52+/-0.15 mmo l l(-1), P<0.05) but not in the controls (2.51+/-0.24 vs. 2.57+/-0.28 mmol l(-1), ns). In conclusion, the decrease of circulating CGRP after MgSO4 infusion in women with PRP provides further evidence that magne sium plays a significant role in the pathophysiology of PRP.