ABSTRACT

Neural cells are open systems that constantly exchange energy with the microenvironment; this energy is used to perform the required work for vital cell functions such as endocytocis, synthesis and transport of macromolecules, exocytosis, cell structure maintenance, locomotion, membrane excitability, adhesion and, in some cases, proliferation. All these cellular functions require a stable microenvironment and conservation of an adequate metabolic rate (Riera et al. 2008). Homeostasis is the maintenance of constant conditions in the internal milieu in spite of changed external conditions (Cannon 1932). Homeostasis also requires large amounts of energy in the form of adenosine triphosphate (ATP) (Riera et al. 2008).