Avtor/Urednik		Eržen, I; Cvetko, E; Obreza, S; Angaut-Petit, D
Naslov		Fiber types in the mouse levator auris longus muscle: a convenient preparation to study muscle and nerve plasticity
Tip		članek
Vir		J Neurosci Res
Vol. in št.		Letnik 59
Leto izdaje		2000
Obseg		str. 692-7
Jezik		eng
Abstrakt		The histochemical composition of the levator auris longus (LAL) muscle has been investigated in adult NMRi mice. Histochemical reaction for myofibrillar adenosine triphosphatase (ATPase) after preincubation in alkaline and acidic media, nicotine amideadenine-dinucleotide dehydrogenase (NADH-dehydrogenase), and alphaglycerophosphate dehydrogenase were performed on cryosections of LAL muscle. Expression of myosin heavy chain (MyHC) isoforms was detected with the immunoperoxidase method applying monoclonal antibodies against MyHC isoforms - 1, -2a, -2x/d, and -2b, as well as by sodium dodecylsulfate (SDS) glycerol gel electrophoresis. The muscle was proven to be a pure fast-twitch muscle. The most numerous fibers in LAL muscles contained MyHC-2b and some MyHC-2a. Histochemically, pure IIA fibers with oxidative metabolism and pure IIB fibers with glycolytic metabolism were detected. In contrast to the majority of mature control muscles, numerous hybrid fibers coexpressing MyHC-2x/d with MyHC-2a or MyHC-2b were present. Both hybrids were oxidativeglycolytic; additionally, some hybrids containing MyHC-2a were oxidative. In one out of six muscles, traces of MyHC-1 were detected both with immunoperoxidase staining and with SDS glycerol gel electrophoresis. Rare fibers that exceptionally expressed small amounts of MyHC-1 always coexpressed MyHC-2a, which is an additional proof that pure type I fibers do not exist in LAL. Due to these histochemical characteristics and to its previously described morphological features, the use of the LAL muscle as a model for various studies, particularly muscle and nerve interactions, is emphasized.
Deskriptorji		MUSCLE, SKELETAL MUSCLE FIBERS, FAST-TWITCH MYOSIN HEAVY CHAINS NEURONAL PLASTICITY MICE ADENOSINETRIPHOSPHATASE NADPH DEHYDROGENASE GLYCEROLPHOSPHATE DEHYDROGENASE HISTOCYTOCHEMISTRY IMMUNOENZYME TECHNIQUES SODIUM DODECYL SULFATE ELECTROPHORESIS, POLYACRYLAMIDE GEL ELECTROPHORESIS, POLYACRYLAMIDE GEL