ROLE OF EDTA AND METALS IN MITOCHONDRIAL CONTRACTION.

STUDIES COMPARING THE STATE OF HYDRATION AND DEHYDRATION OF RAT LIVER MITOCHONDRIA TO THEIR CONTENT OF ATP, CA, AND FATTY ACID, ALONG WITH THE RATE OF ATP HYDROLYSIS, AS WELL AS MICROSCOPIC APPEARANCE OF MITOCHONDRIA, HAVE LED TO THE FOLLOWING GENERALIZATIONS: 1. The competition between cationic translocations and water translocation for the available chemical energy (ATP) determines under many circumstances the water content of mitochondria. 2.

OSMOTIC AND METABOLIC ALTERATIONS OF MITOCHONDRIAL SIZE.

Sustained contraction (dehydration) of rat liver mitochondria can be readily produced by increasing the tonicity of the outside media, provided Ca(++) is removed by EDTA, fatty acids are removed by albumin, and a source of chemical energy (mitochondrial substrate or ATP) is present. This was demonstrated both gravimetrically and turbidimetrically. It was also demonstrated that the net movement of sucrose and H(2)O under altered conditions of tonicity in mitochondria was dependent on the state of the mitochondria; e.