慢性损伤对骨骺软骨板超微结构的影响

EFFECT ON ALTRASTRUCTURE OF CHONDROCYTE IN THE EPIPHYSEAL PLATE AFTER CHRONIC COLLISION INJURY

本文报道了慢性撞击幼兔前肢近端2～4周,桡骨远端骨骺软骨板软骨细胞形态即改变,粗面内质网扩张,线粒体蜡肠样及球拍样肿胀;撞击6～8周,线粒体髓样变,核内异染色质边集;8～12周,细胞器减少,核变形,碎裂,核膜消失。本文从超微病理学证实,慢性撞击不仅可以引起囊外压力性骨骺软骨板软骨细胞的变性,而且可以引起小灶性坏死,并认为这种坏死与长时间外力反复作用引起的局部缺血有着因果关系。

Five young rabbits were divided into 5 groups (2, 4, 6, 8 and 12 week), one rabbit in each group.A special collision unit was used in the experiment by which the distal ends of the right fore legs of rabbits were struck repeatedly. Altrastructure changes of chondrocyte at the epiphyseal plate in the distal endof radius were observed in H-500 electron microscope. In two and four week groups, organaelles swelling was found such as rough endoplasmic reticulum andmitochondria, especially mitochondria swelling which showed different shapes like sausagge and racket.Space around nucleus increased, nucleus shape changed, myeline structure in the mitochondria and chroma- tin margination in the nucleus were found in the six and eight week groups. Altrastructure changes weremore serious in the eight and twelve week groups than other groups. Necrosis of chondrocyte was appearedsuch as part organaelles dissolved or disappeared, nucleus brokeu aud nucleus memberane disappeared. The results showed in altrastructure pathology that chronic collision injury can cause not only degeneration of chondrocyte in the pressure epiphyseal plate but necrosis of chondrocyte as well. It concluses that chondrocyte necrosis is related to local ischemia resulted from chronic collision injury.