Expression of specific IGFBPs is associated with those of the proliferating and differentiating markers in regenerating rat plantaris muscle.
To examine the relationship between specific insulin-like growth factor (IGF)-binding proteins (IGFBPs) and myogenesis during muscle regeneration in vivo, we measured mRNA expression of IGFBPs and myogenic markers in rat plantaris muscle after bupivacaine administration. IGF-I Ea, MGF, IGFBPs and myogenic marker mRNAs were analyzed 12, 24, 48 and 72 h after bupivacaine injection. IGFBP-1, -2, -3 and -4 proteins were immunostained after the treatment. MGF, IGF-I Ea and IGFBP-4 mRNAs started to increase 12 or 24 h after bupivacaine injection and increased further after that. IGFBP-1, -2, -3 and -4 proteins were strongly stained in the immature muscle fiber nuclei and the extracellular matrix after bupivacaine injection. PCNA, MyoD, IGFBP-2 and IGFBP-3 mRNAs increased at 12 or 24 h and did not show further increases after that. Myogenin, p21, IGFBP-1 and IGFBP-5 mRNAs sharply increased after 72 h. These results suggest that specific IGFBPs are individually expressed and differently associated with the expression of myogenic markers in regenerating muscles.
Department of Integrated Human Sciences, School of Dentistry, Health Sciences University of Hokkaido, Kanazawa, Ishikari-Tobetsu, Hokkaido, 061-0293, Japan. yama@hoku-iryo-u.ac.jp.
Akihiko
A
Yamaguchi
Research Center of Physical Fitness, Sports and Health, Toyohashi University of Technology, Toyohashi, Aichi, Japan.
Kunihiro
K
Sakuma
Department of Pharmaceutical Sciences, Suzuka University of Medical Science, Suzuka, Mie, Japan.
Takahiko
T
Fujikawa
Department of Integrated Human Sciences, School of Nursing and Social Services, Health Sciences University of Hokkaido, Kanazawa, Ishikari-Tobetsu, Hokkaido, Japan.
Isao
I
Morita
D000818:Animals; D000943:Antigens, Differentiation / Q000235:genetics* / Q000378:metabolism*; D002454:Cell Differentiation / Q000502:physiology; D049109:Cell Proliferation; D050759:Cyclin-Dependent Kinase Inhibitor p21 / Q000235:genetics / Q000378:metabolism; D018969:Insulin-Like Growth Factor Binding Proteins / Q000096:biosynthesis* / Q000235:genetics* / Q000378:metabolism; D008297:Male; D024510:Muscle Development / Q000235:genetics; D009132:Muscles / Q000166:cytology / Q000378:metabolism / Q000502:physiology*; D017570:MyoD Protein / Q000235:genetics / Q000378:metabolism; D018008:Myogenin / Q000235:genetics / Q000378:metabolism; D018809:Proliferating Cell Nuclear Antigen / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics; D051381:Rats; D017208:Rats, Wistar; D012038:Regeneration / Q000235:genetics / Q000502:physiology*
D000943:Antigens, Differentiation; D050759:Cyclin-Dependent Kinase Inhibitor p21; D018969:Insulin-Like Growth Factor Binding Proteins; D017570:MyoD Protein; D018008:Myogenin; D018809:Proliferating Cell Nuclear Antigen; D012333:RNA, Messenger