Changes produced by experimental hypothyroidism in fibre type composition and mitochondrial properties of rat slow and fast twitch muscles.
Experimental hypothyroidism changes the fibre type percentual composition of soleus and extensor digitorum longus muscles of rat. In both cases it has been observed an increase in the type I and a decrease in the type II fibre percentages. A reduction of proton passive permeability of mitochondrial membrane is observed in experimental hypothyroidism together with a decrease in the docosahexaenoic acid content of the mitochondrial total lipids. This change in the lipid composition could produce the reduction of the mitochondrial membrane proton passive permeability and thus, reduces state 4 mitochondrial respiratory rate of rat skeletal muscles.
Instituto de Medicina Experimental, Universidad Central de Venezuela, Caracas.
A
A
Crespo-Armas
V
V
Azavache
S H
SH
Torres
B
B
Anchustegui
Z
Z
Cordero
D000818:Animals; D004281:Docosahexaenoic Acids / Q000378:metabolism; D005227:Fatty Acids / Q000032:analysis; D007037:Hypothyroidism / Q000503:physiopathology*; D008297:Male; D008931:Mitochondria, Muscle / Q000737:chemistry / Q000502:physiology*; D018485:Muscle Fibers, Skeletal / Q000502:physiology*; D018482:Muscle, Skeletal / Q000503:physiopathology*; D010101:Oxygen Consumption; D051381:Rats; D017207:Rats, Sprague-Dawley
D005227:Fatty Acids; D004281:Docosahexaenoic Acids