Effect of dystrophin deficiency on selected intrinsic laryngeal muscles of the mdx mouse.
BACKGROUND
Intrinsic laryngeal muscles (ILM) show biological differences from the broader class of skeletal muscles. Yet most research regarding ILM specialization has been completed on a few muscles, most notably the thyroarytenoid and posterior cricoarytenoid. Little information exists regarding the biology of other ILM. Early evidence suggests that the interarytenoid (IA) and cricothyroid (CT) may be more similar to classic skeletal muscle than their associated laryngeal muscles. Knowledge of the IA and CT's similarity or dissimilarity to typical skeletal muscle may hold implications for the treatment of dysphonia.


OBJECTIVE
The purpose of this study was to further define IA and CT biology by examining their response to the biological challenge of dystrophin deficiency.


METHODS
Control and dystrophin-deficient superior cricoarytenoid (SCA; mouse counterpart of IA) and CT muscles were examined for fiber morphology, sarcolemmal integrity, and immunohistochemical detection of dystrophin.


RESULTS
Despite the absence of dystrophin, experimental muscles did not show disease markers.


CONCLUSIONS
The SCA and the CT appear spared in dystrophin-deficient mouse models. These laryngeal muscles possess specializations that separate them from typical skeletal muscle. Considered in light of previous research, the CT and IA may represent transitional form of muscle, evidencing properties of typical and specialized skeletal muscle.
Fry
Lisa T
LT
Department of Communication Disorders, Marshall University, 1 John Marshall Drive, Huntington, WV 25755, USA. thomasl@marshall.edu
Stemple
Joseph C
JC
Andreatta
Richard D
RD
Harrison
Anne L
AL
Andrade
Francisco H
FH
D000818:Animals; D016189:Dystrophin / Q000172:deficiency* / Q000378:metabolism; D007150:Immunohistochemistry; D007821:Laryngeal Muscles / Q000033:anatomy & histology / Q000378:metabolism* / Q000473:pathology*; D007830:Larynx / Q000033:anatomy & histology; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D018101:Mice, Inbred mdx; D008954:Models, Biological; D018485:Muscle Fibers, Skeletal / Q000378:metabolism / Q000473:pathology; D009136:Muscular Dystrophies / Q000378:metabolism* / Q000473:pathology*; D012508:Sarcolemma / Q000378:metabolism / Q000473:pathology
D016189:Dystrophin