The role of calcium in endotoxin-induced release of calcitonin gene-related peptide (CGRP) from rat spinal cord

• Published in: Science China. Life sciences Vol. 40; no. 4; pp. 437 - 442
• Main Author: 唐跃明 韩启德 王宪
• Format: Journal Article
• Language: English
• Published: China Springer Nature B.V 01-08-1997
• Subjects: Caffeine; Calcitonin; Calcitonin gene-related peptide; Calcium; Calcium (extracellular); Calcium (intracellular); Calcium channels (N-type); Calcium-binding protein; Calmodulin; Capsaicin; cord; endotoxin; gene-related; Magnesium chloride; Nifedipine; peptide; rat; Ruthenium red; Ryanodine; Sensory neurons; spinal; Spinal cord
• ISSN: 1674-7305; 1006-9305; 1869-1889; 1862-2798
• DOI: 10.1007/BF02881739

In the present study, the role of calcium in endotoxin-induced CGRP release was studied. 2 .5-50 μg/mL endotoxin and 1 -10 mmol/L caffeine caused concentration-dependent increase of CGRP release from rat spinal cord in vitro. However, no additive effect could he found when caffeine and endotoxin were concomitantly incubated. By using capsaicin, Ca2+-free medium, Omega-Conotoxin, nifedipine, W-7, ryanodine, MgCl2, Tris-ATP, rutheni-um red, the results indicate that the release of CGRP evoked by endotoxin from the sensory fibers of rat spinal cord is dependent on extracellular calcium. After entering into the cell through the N-type calcium channel, calcium binds to calmodulin, and triggers calcium release from intracellular calcium store by activating the caffeine-sensitive but ryan-odine-insensitive mechanism.