The Changes of Myosin Heavy Chain Isoforms after Tenotomy on Extraocular Muscle Layers of Rabbits.

Lee, Hyeon Chul; Oh, Sei Yeul; Chang, Bong Leen

Original Article

Journal of the Korean Ophthalmological Society 2003;44(10):2402-2409.
Published online October 1, 2003.

The Changes of Myosin Heavy Chain Isoforms after Tenotomy on Extraocular Muscle Layers of Rabbits.

Hyeon Chul Lee, Sei Yeul Oh, Bong Leen Chang

¹Department of Ophthalmology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.syoh@smc.samsung.co.kr
²Department of Ophthalmology, Seoul National University College of Medicine, Seoul, Korea.

백색가토 외안근건절단술 후 안구층 및 안와층의 Myosin Heavy Chain Isoform들의 변화

이현철 ( Lee Hyeon Cheol ) , 오세열 ( O Se Yeol ) , 장봉린 ( Jang Bong Lin )

Abstract

PURPOSE
Extraocular muscle (EOM) consists of two layers, the global and the orbital layer, which are readily distinguished by their histopathology. This study was conducted to investigate the changes of myosin heavy chain (MHC) and MHC isoforms of the global and the orbital layers of EOM after tenotomy. METHODS: Twenty four New Zealand white rabbits were used. The rectus muscles were harvested on day 3, week 1, week 2, week 3, week 4, and week 8 after EOM tenotomy. The change of MHC amount was measured using an electrophoresis. The changes of MHC isoforms were also measured quantitatively using western blot immunostaining. RESULTS: The amount of total MHC, fast MHC isoform, and slow MHC isoform decreased maximally at 1-week after EOM tenotomy and recovered at 4-week and 8-week after tenotomy. There was no significant change in the amount of the neonatal and developmental MHC isoform. CONCLUSIONS: Fast and slow MHC isoform changed mainly due to the changes in the global layer rather than in the orbital layer after EOM tenotomy.

Key Words: Extraocular muscle;Global layer;Myosin heavy chain;Orbital layer;Tenotomy