Quantitative Analysis of Myosin Heavy Chain (MHC) mRNA expression in Thyropharyngeus muscle and Cricopharyngeus muscle in Rats.
- Author:
Young Sil PARK
1
;
Hak Hyun JUNG
;
Soon Yhul NAM
Author Information
1. Department of Otolaryngology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
- Publication Type:Original Article
- Keywords:
Competitive PCR;
gene expression;
thyropharyngeus muscle;
cricopharyngeus muscle;
rat
- MeSH:
Animals;
Deglutition;
Gene Expression;
Hand;
Muscles;
Myosin Heavy Chains*;
Myosins*;
Pharyngeal Muscles*;
Polymerase Chain Reaction;
Protein Isoforms;
Rats*;
RNA Isoforms;
RNA, Messenger*
- From:Korean Journal of Otolaryngology - Head and Neck Surgery
2000;43(3):300-305
- CountryRepublic of Korea
- Language:Korean
-
Abstract:
BACKGROUNDS: The inferior pharyngeal constrictor muscle (IPC), which consists of the thyropharyngeus (TP) and cricopharyngeus (CP) muscles, plays an important role during deglutition, but their function is different when analysed by radiographic, manometric and electromyographic studies. OBJECTIVES AND MATERIALS: The purpose of this study is to quantify the expression levels of MHC mRNA isoforms (2B, 2X, 2A, 2L, beta-cardiac, neonatal and embryonic) in thyropharyngeus and cricopharyngeus muscles of rats using competitive PCR. RESULTS: The thyropharyngeus muscle was mainly consisted of three fast-twitching MHC isoforms, mostly 2X isoform (85.2%). On the other hand, the cricopharyngeus muscle contained two-third of fast-twitching isoforms(65.1%) and one-third of neonatal MHC(34.9%). CONCLUSIONS: The thyropharyngeus muscle could be characterized as a fast-twitching muscle and the cricopharyngeus muscle is probably considered as a sarcomeric regenerating muscle that is caused by frequently mechanical damage on deglutition.
