Effects of chondrocyte phenotypic stability by mechanical stimulation

Objective To explore the stability of chondrocyte phenotypes by the mechanical stimulation.Methods Rabbit knee articular cartilage cells obtained by enzymatic digestion were cultured and passaged. The chondrocytes were cultivated in unvarying (0, 1 Hz) frequency and different mechanical pressure (500, 1000, 1500 μe) on four-point bending cell culture plate. Chondrocyte collagen type Ⅰ and type Ⅱ were analyzed immunohistochemically, and collagen Ⅰ, Ⅱ and proteoglycan mRNA expression was detected by polymerase chain reaction (PCR).Results Regularly cultured chondrocytes to the 5th generation or later lost phenotypes to differentiation. After stimulation by the dynamic mechanical stress, cartilage cells to the 8th generation still expressed the type Ⅱ collagen and proteoglycans.Conclusion Mechanics can stimulate the synthesis of chondrocytes and maintain the stability of chondrocyte phenotype. Key words: Chondrocytes;  Mechanical stress;  Phenotype