Category: I

  • Insulin release

    Insulin release by the β cells of the pancreas involves a number of interrelated metabolic reactions in both the cytosol and the mitochondria. The islet must sense that blood glucose levels are rising. This is a critical step in insulin release. The glucose-phosphorylating enzyme, glucokinase, serves this function. GLUT 2 transports glucose through the plasma…

  • Insulin receptor substrate 1

    A cytosolic compound that associates with proteins containing SH2 domains; that is, tyrosine phosphatase when insulin binds to its receptor on the cell membrane.  

  • Insulin receptor

    Protein that is embedded in the plasma membrane of the insulin-sensitive cell. When insulin is bound to its receptor, a cascade of signals is generated that includes the movement of glucose transporters to the plasma membrane and the subsequent metabolism of the incoming glucose. Mutations in the genes for the receptor phenotype as diabetes mellitus.…

  • Insulin pump

    A small instrument that senses changes in blood glucose and delivers insulin subcutaneously so as to maintain an optimal insulin-glucose relationship. An appliance for delivering insulin to people with type 1 diabetes. The pump steadily injects insulin into the body in a pattern that is similar to the way the pancreas normally releases insulin into…

  • Insensible water loss

    Water lost through the skin and through the lungs that is not noticed by the individual.  

  • Inositol phosphate

    A phospholipid in the plasma membrane that releases phosphoinositol when stimulated by phospholipase C.  

  • Information bias

    Errors in the necessary information, leading to errors in the classification of subjects. The misclassification can be characterized as random (or nondifferential) or differential.  

  • Indispensible nitrogen

    Nitrogenous compounds that must be sustained for good health.  

  • Indirect calorimetry

    Determination of energy expenditure using the measurement of oxygen consumption. One approach that quantifies the thermal energy generated by biological entities through their respiratory activities. An approach whereby the quantification of respiratory gas exchange throughout the entirety of the body is employed to approximate the quantity of energy generated via the process of oxidation.  

  • Independent action

    Actions of substances at different sites of action, with no interaction between the components. Different mechanisms can underlie the same effect and this may mean that the effects of some components of a mixture consisting of a large number of substances are similar and are integrated into an overall effect (effect integration).