Abstract: To study the effects of scallop skirt glycosaminoglycan (SS-GAG) on ET1 and NO secretion of ECV304 damaged by highly concentrated glucose. Methods The vascular endothelial cell ECV304 was cultured in vitro, and the damage mode1 of endothelia1 cells was established by highly concentrated glucose．Different concentrations of SS-GAG was mixed with cell culture fluid containing highly concentrated glucose (55.5mmol/L), and the cell morphology was observed after cultured for 12h, 24h, 36h and 48h, respectively. Nitric oxide (NO) inside cells were determined by the assay of nitric acid reductase. Radioimmunoassay was used to determine ET-1. ResultsCell morphology was changed and proliferation was depressed under the highly concentrated glucose, and a dose-dependent reaction occurred. SSGAG weakened the damage effects of highly concentrated glucose, and made these cells keep their normal morphology. The concentration of ET-1 in the cell culture supernatant was increased compared with the normal control group. Differences had statistics meaning compared with the normal control group (P＜0.01). And the NO inside cells initially increased, and then reduced. Differences had statistics meaning compared with the normal control group (P＜0.01). There were obvious differences between the SS-GAG group and the negative control group. With modulation of SS-GAG, ET-1 and NO inclined to the normal level,difference occurred between the SSGAG and the highly concentrated glucose groups. Difference had statistics meaning compared with the highly concentrated glucose group (P＜0.01) but not with the normal control group (P＞0.05). ConclusionsHighly concentrate glucose has obvious damaged effects on vascular endothelial cells, which may induce the cell morphology change, dysfunction, ET1 increase and NO secretion. SS-GAG will weaken this damage and protect the cells by modulating the balance of ET1 and NO.

Key words: Scallop, Glycosaminoglycan, Glucose, Vascular endothelial cell, Endothelin 1, Nitric oxide