Role of acid-sensing ion channel 1 a in matrix turnover and MAPK expression of articular chondrocytes of rats / 中国药理学通报

ABSTRACT

Aim TostudytheroleofASIC1aonthe matrix turnover and MAPK expression of the rat articu-lar chondrocytes with extracellular acidosis. Methods ArticularchondrocyteswereisolatedfromSprague-Dawley rats, and their phenotype was determined by toluidine blue and immunocytochemical staining. The GAG content of cell culture supernatant was deter-mined by dimethyl-methylene blue spectrophotometric assay, while Hyp content by chloramine T assay. ELISA assay was used to measure MMP-2 , TIMP-2 content. Furthermore, the ERK1/2, p38 MAPK phos-phorylation protein expression levels were tested by Westernblotassay.Results ASIC1acontributedto the effect of GAG, Hyp and TIMP-2 levels reduction induced by extracellular acidification, while the effect of MMP-2 was weaker. Moreover, ASIC1a could in-crease the ERK1/2 , p38 MAPK phosphorylation pro-teinexpressionlevels.Conclusion ASIC1acould regulate rat articular chondrocytes matrix turnover via ERK1/2 and p38 MAPK signaling pathway, and there-by inhibit the rat articular cartilage damage induced by acidosis.