Developmental studies of the expression of myosin heavy chain isoforms in cultured human muscle aneurally and innervated with fetal rat spinal cord.
To study the influence of innervation of human muscle fiber type differentiation, we performed immunohistochemical studies using three monoclonal antibodies (McAbs) to myosin heavy chain (MHC) on cultured human muscles at different developmental stages. McAbs QM 355 (McAb-1), E 35-3 (McAb-2) and SM 1-11-2 (McAb-3) bound to fiber types I, IIA, IIB and IIC, types IIA, IIB and IIC, and type I, respectively. At the mononucleated cell stage the majority was immunonegative to the three McAbs; however, a few myoblasts were immunopositive to the McAb-1. They were also weakly stained with McAb-2 but not with McAb-3. In aneurally cultured myotubes (AMs), all myotubes were stained with the McAb-1 and 92.1% of AMs were positive to the McAb-2, whereas only a few (0.9%) AMs were immunopositive to the McAb-3. In contracting muscle fibers in an innervated area (CMis), which were co-cultured with fetal rat spinal cord explants, the percentage of the McAb-3-positive CMis was significantly increased (8.3%; P < 0.01) compared with that of AMs (0.9%). The double staining with the McAbs-2 and -3 clearly showed that slow MHC-positive muscle fibers without fast MHC only appeared in CMis. This is the first report of the neuronal influence on the expression of human adult slow MHC isoform derived from adult human satellite cells in vitro.
Kameda
N
N
Department of Neurology, Tokyo Medical and Dental University School of Medicine, Japan.
Kobayashi
T
T
Park-Matsumoto
Y C
YC
Tsukagoshi
H
H
Shimizu
T
T
D000251:Adenosine Triphosphatases / Q000378:metabolism; D000293:Adolescent; D000328:Adult; D000818:Animals; D000911:Antibodies, Monoclonal; D002642:Chick Embryo; D046508:Culture Techniques; D016332:Fetal Tissue Transplantation / Q000502:physiology*; D006801:Humans; D015151:Immunoblotting; D007124:Immunoenzyme Techniques; D007150:Immunohistochemistry; D051379:Mice; D008807:Mice, Inbred BALB C; D008875:Middle Aged; D009132:Muscles / Q000294:innervation / Q000378:metabolism*; D009210:Myofibrils / Q000201:enzymology; D009218:Myosins / Q000096:biosynthesis*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013116:Spinal Cord / Q000502:physiology / Q000637:transplantation*
D000911:Antibodies, Monoclonal; D000251:Adenosine Triphosphatases; D009218:Myosins