Thyroid hormones up-regulate Ca-channels in cultured skeletal muscle of the rat.
The effects of thyroid hormones (TH) were examined on the expression of slow Ca2(+)-channels in cultures of rat skeletal muscle. Myotubes were treated with TH at age 5-7 days in vitro, and measurements of specific binding of the dihydropyridine Ca-channel antagonist [3H]PN200-110 were made beginning 12 h later. TH caused a dose-related increase in PN200-110 binding sites with a lower affinity for the ligand than in control cells. The effect was blocked by simultaneous treatment with cycloheximide or actinomycin-D. The results indicate that TH increase gene expression of slow Ca2(+)-channels of skeletal muscle.
Brodie
C
C
Department of Life Sciences, Bar-Ilan University, Ramat-Gan, Israel.
Sampson
S R
SR
D000818:Animals; D000831:Animals, Newborn / Q000502:physiology; D015220:Calcium Channels / Q000187:drug effects / Q000378:metabolism*; D002478:Cells, Cultured; D017275:Isradipine; D007700:Kinetics; D009124:Muscle Proteins / Q000378:metabolism; D009132:Muscles / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D010069:Oxadiazoles / Q000378:metabolism; D051381:Rats; D015222:Sodium Channels / Q000187:drug effects; D013779:Tetrodotoxin / Q000494:pharmacology; D013963:Thyroid Hormones / Q000494:pharmacology*; D015854:Up-Regulation / Q000187:drug effects*
D015220:Calcium Channels; D009124:Muscle Proteins; D010069:Oxadiazoles; D015222:Sodium Channels; D013963:Thyroid Hormones; D013779:Tetrodotoxin; D017275:Isradipine