Oxygen basal metabolism

Basal metabolic rate The rate of oxygen consumption by a person at rest. 

A number of parameters such as, e.g., renal clearance, basal oxygen consumption (metabolic rate), area under the curve (AUC), maximum metabolic velocity, or cardiac output correlate to the body weight to the power of 0.75 Further support for the power of 0.75 comes from a more... 

Z)-2,3-Methanothyronine 59 and its dibromo derivative 60 have comparable activity with the thyroxine 61, a thyroid hormone [66], which exhibited thyro-mimetic activities in basal metabolism and antigoiter tests (comparison of oxygen consumption and heart rate in normal and thyroidectomized rats) but did not have an inhibitory action on the metabolism developed by triiodothyronine [66]. (Z)-2,3-Methanohistidine 62, tested on rat liver, is an effective inhibitor of histidine decarboxylase, Eq. (23) [67]. 

Pharmacology Thyroid hormones enhance oxygen consumption by most tissues of the body and increase the basal metabolic rate and metabolism of carbohydrates, lipids, and proteins in the body. 

Production Site Adrenal medulla and chromaffin cells in gut Metabolic effects increases oxygen consumption. temperature, basal metabolic rate, gluconeogenesis Pituitary effects stimulates production and release of ACTH and corticoids ... 

The functions of the thyroid hormones and thus of iodine are control of energy transductions. These hormones increase oxygen consumption and basal metabolic rate by accelerating reactions in nearly ail cells of the body. A part of this effect is utlribuicd lo increase in activity of many enzymes. Additionally, protein synthesis is affected by the thyroid hormones. 

In a basal metabolism measurement timed at exactly 6 minutes, a patient exhaled 52.5 L of air, measured over water at 20°C. The vapor pressure of water at 20°C is 17.5 torn The barometric pressure was 750 torn The exhaled air analyzed at 16.75 volume % oxygen, and the inhaled air at 20.32 volume % oxygen (both on a dry basis). Neglecting any solubility of the gases in water and any difference in total volumes of inhaled and exhaled air, calculate the rate of oxygen consumption by the patient in cm3 (S.T.P.) per minute. 

The mouse anoxia or oxygen-consumption test is based on the stimulation of the basal metabolic rate by thyromimetic compounds. Mice or other small animals are placed in airtight containers of known volume and their survival time is determined (34). 

Chlorophenols block adenosine triphosphate (ATP) production, without blocking the electron transport chain. They inhibit oxidative phosphorylation, which increases basal metabolic rate and increases body temperature. As body temperature rises, heat-dissipating mechanisms are overcome and metabolism is accelerated. Adenosine diphosphate (ADP) and other substrates accumulate, and stimulate the electron transport chain further. This process demands more oxygen in a futile effort to produce ATP. Oxygen demand quickly surpasses oxygen supply and energy reserves of the body become depleted. 

The exact mechanism of action is not well understood. Thyroid hormones are needed for metabolism, growth, and development. Most organ systems are affected by thyroid hormones. Thyroid hormones cause an increase in the basal metabolic rate, in oxygen consumption, and in the metabolism of... 

Thyroid hormones have many important biological effects. A major function is their control of the basal metabolic rate and calorigenesis through increased oxygen consumption in tissue via the effects of thyroid hormone on membrane... 

Metabolic Effects. The characteristic effects of 2,4-DNP are elevation of the basal metabolic rate (often easured indirectly as oxygen consumption), elevation of body temperature and increased perspiration (humans). The body compensates for these effects by increasing the respiratory rate to deliver more oxygen to the tissues. As body temperature rises, peripheral vasodilation occurs as a cooling mechanism and the pulse rate rises to maintain the circulation. 

DNP is an uncoupler of oxidative phosphorylation. In humans or animals exposed to 2,4-DNP, the energy produced from the Krebs cycle is not stored in adenosine triphosphate (ATP), but is released as heat. This short-circuiting of metabolism results in the characteristic clinical signs of increased basal metabolic rate, oxygen consumption, perspiration, and body temperature. Elevated environmental temperatures may compromise the body s ability to dissipate the heat. 

The maintenance of cellular homeostasis implies the dynamic coordination of cellular processes to finely compensate for subtle variations of the external and internal environments (e.g., pH, osmolarity, nutrients, and oxygen supply) but also to monitor and regulate intracellular signalling and compartmentalization. Cellular stress occurs when a threat to homeostasis is detected by highly reactive and efficient protective mechanisms. Depending on the intensity (dose) and duration (exposure) of the stress, these defenses can either cope without any observable change in cellular homeostasis or be overcome, resulting in a detectable shift from basal metabolic or cellular functions. 

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