title: Injury of the cell's respiratory system by heat and by formaldehyde. Thermokinetics and early molecular events.
abstract: This is a study of the manner in which the respiratory system of the cell is injured either by elevated temperature or by exposure to diluted formaldehyde. Molecular mechanisms were identified by thermokinetic measurements. The rates at which respiratory failure developed in mouse liver slices in an injurious environment were measured at various temperatures. The data were fitted to the Arrhenius equation, and the effective activation energies of the injury processes were calculated. These data show that (1) the thermokinetics of injury to the cell's respiratory system, whether by thermal or chemical means, follows the Arrhenius law. (2) Thermal injury of the cell's respiratory system has a high activation energy, indicating that the critical, rate-determining event is a protein denaturation. Other mechanisms such as imbalance of metabolic reaction rates and thermal liquefaction of membrane lipids can be ruled out. (3) Repression of cell respiration by diluted formaldehyde has an activation energy compatible with a chemical reaction but low enough to exclude protein denaturation as a mechanism.
mesh_terms: D000818:Animals; D005557:Formaldehyde / Q000633:toxicity*; D006358:Hot Temperature; D007700:Kinetics; D008099:Liver / Q000378:metabolism; D051379:Mice; D010101:Oxygen Consumption / Q000187:drug effects; D011489:Protein Denaturation; D013816:Thermodynamics
chemical_list: D005557:Formaldehyde