Interaction of insulin and chromium (III) on mitochondrial swelling

¹ Division of Biochemistry, Walter Reed Army Institute of Research, Walter Reed Army Medical Center, Washington, D.C.

Swelling of rat liver mitochondria was significantly increased by 1.6 x 10^–3 mm concentrations of insulin, but not with 1.6 x 10^–4 mm insulin. 6 x 10^–5 µmoles of chromium (III) per milliliter in the absence of insulin did not significantly increase swelling rates. Addition of insulin and chromium at concentrations which were ineffective by themselves, led to a considerable increase of mitochondrial swelling. On the basis of these and other data, it is proposed that trace amounts of chromium facilitate the tissue-insulin interaction by forming a complex with the intrachain disulfide of the hormone.