Phosphate metabolism during muscular contraction in starved frogs (Rana catesbeiana).
1. The muscle tension and the state of high-energy phosphate metabolism during contraction of the sartorius muscle in frogs (Rana catesbeiana) starved for 1-5 months was studied by in vivo 31P-NMR spectrometry. 2. Muscle tension began to decrease after 2-month starvation compared with the control group and decreased to about one-third of the control value after a 5-month starvation. 3. Muscle contraction induced by electrical stimulation or the use of anaerobic perfusion fluid did not decrease the concentration of creatine phosphate (PCr) or beta-ATP, and only negligibly changed the PCr/Pi ratio from starvation. 4. These results suggest a decrease in creatine kinase activity in the muscle of starved frogs.
Chiba
A
A
Department of Physiology, Kinki University School of Medicine, Osaka, Japan.
Takashima
M
M
Hamaguchi
M
M
Chichibu
S
S
D000818:Animals; D001835:Body Weight / Q000502:physiology; D004558:Electric Stimulation; D004734:Energy Metabolism / Q000502:physiology; D009682:Magnetic Resonance Spectroscopy; D009119:Muscle Contraction / Q000502:physiology*; D009132:Muscles / Q000378:metabolism* / Q000502:physiology; D010710:Phosphates / Q000378:metabolism*; D010725:Phosphocreatine / Q000378:metabolism; D010759:Phosphorus Isotopes; D011892:Rana catesbeiana; D013217:Starvation / Q000378:metabolism
D010710:Phosphates; D010759:Phosphorus Isotopes; D010725:Phosphocreatine