Temperature muscle

Most of the oxygen consumed by an animal is used by its muscle, and in the presence of a fall in local temperature, oxygen supply to ischemic muscle is adequate for normal metabolic demands, as evidenced by the persistence of a normal nucleotide pattern. However, at an air temperature of 30°C, the fall in muscle temperature is prevented, and muscle chemistry then indicates inadequate oxygen supply. 

Humans seek and want thermal comfort, even at work in industrial settings. Clothing, activities, posture, location, and shelter are chosen, adjusted, altered, and sought consciously and unconsciously to reduce discomforts and enable us to focus more on the other tasks of life. Discomfort can contribute to mistakes, productivity decreases, and industrial accidents. " Thermal discomfort results from the physiological strain of thermoregulation. The strain can be in the form of altered body temperatures, sweating and excessive skin moisture, muscle tension and stiffness, shivering, and loss of dexterity. A small... 

COLD Xblood flow to skin (vasocoiistriction, muscle tension and shivering t, body temperatures X, metabolism T... 

Bratton, D. 1.., Tanaka, D. T, and Gnmstein, M. M. (1987). Effects of temperature on cholinergic contractility of rabbit airway smooth muscle. /. Appl. Physiol. 63, 1933-1941. 

Souhrada, M., and Souhrada, J. E (1981). The direct effect of temperature on airway smooth muscle. Resp. Physiol. 44, 311-323. 

Malignant hyperthermia (MH) is an autosomal-dominant pharmacogenetic disorder that is triggered by exposure to inhalation of general anesthetics, such as halothane. In susceptible individuals, these drugs can induce tachycardia, a greatly increased body metabolism, muscle contracture and an elevated body temperature (above 40°C) with a rapid rate of increase. Many cases of MH are linked to a gene for type 1 ryanodine receptor (RyRl). 

Myotonia is muscle stiffness, in which muscle relaxation after voluntary contraction is impaired. Mutations in several ion channel genes (Cl, Na, Ca, K channels) can cause myotonias, which can sometimes be differentiated clinically (e.g. paramyotonia is cold-sensitive). C1C-1 mutations cause pure myotonia congenita which is not sensitive to temperature. Channel myotonia comes in a recessive (Becker type)... 

Muscles are elegant devices, developed through millions of years of evolution to transform chemical energy into mechanical energy and heat at constant temperature, that is, outside the limitations imposed on internal... 

The second of these steps, the rate of hydrolysis at 12 °C, measured by analysis of the ADP content in fibers rapidly frozen at different times after ATP release from caged-ATP, is 40-60 s (Ferenczi, 1986) which is similar to the rate of active force increase at 20°C once the difference in temperature has been accounted for. This rate is similar to that measured in solution however, and is not rate limiting in solution. Therefore, force generation in the caged-ATP experiments could be limited by hydrolysis, or more likely, by a step following hydrolysis such as Pj release. The idea that release of phosphate is linked to force production in muscle... 

Wiles, C.M. Edwards, R.H.T. (1982). The effect of temperature, ischemia and contractile activity on the relaxation rate of human muscle. Clin. Physiol. 2,485-497. 

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