Histotoxic hypoxia (also called histoxic hypoxia) is the inability of cells to take up or use oxygen from the bloodstream, despite physiologically normal delivery of oxygen to such cells and tissues. Histotoxic hypoxia results from tissue poisoning, such as that caused by cyanide (which acts by inhibiting cytochrome oxidase) and certain other poisons like hydrogen sulfide (byproduct of sewage and used in leather tanning).
Causes
Histotoxic hypoxia refers to a reduction in ATP production by the mitochondria due to a defect in the cellular usage of oxygen.
Treatments
Cyanide antidote kit is a widely used method in treating cyanide induced histotoxic hypoxia. It consists of three different parts that are administered one after the other. The three parts are amyl nitrite, sodium nitrite, and sodium thiosulfate.
Ischemia
Histotoxic hypoxia can be a consequence of ischemia in the case of stroke or inflammation. In the case of inflammation, neuro-inflammatory diseases like Alzheimer's disease, Parkinson's disease and Multiple Sclerosis can all lead to histotoxic hypoxia. During a stroke, there is an interruption in the blood supply followed by reperfusion which leads to histotoxic hypoxia because of an accumulation of reactive oxygen species (ROS).
See also
- Hypoxia