Factors affecting the maximum yield of non protein nitrogen from skeletal muscles

Attempt was made to study the factors that affect maximum yield of nonprotein nitrogen from various skeletal muscles. The results showed that sonification was the most effective method out of the various extraction procedures used for the extraction of NPN, while the use of tungstic acid as protein precipitant was most suitable. The pH studies showed that pH 2 gave the optimal yield of NPN. Results of the coloured sample dilutions showed exponential relationship between optical densities and the concentrations of NPN used. The results are discussed in terms of the factors affecting maximum yield of NPN along with the significance of the term half optical density dilution

Independence of force velocity relationship of skeletal muscles to denervation at higher temperatures

Effect of chronic denervation and temperature was studied on the force velocity relationship of rat diaphragm muscle. The muscles were denervated for 15 - 20 days and force of contraction and velocity of shortening were calculated according to Hill [1938] using isotonic contraction data. The results showed that the force velocity relationships were not altered at 35°C to 25°C. However, a change in this parameter was observed in the denervated muscles at 15°C. It is suggested that the velocity of shortening is independent of changes in the series elasticity of the denervated muscle at higher temperatures