Radiosensitivity and Biological Properties of Two Tumor Types Indigenous to the Same Host. IX. Swelling Properties of Mitochondria Isolated from Mouse Tumor and Liver Tissue. ∗

Abstract

Summary

Isolated mitochondria from 2 tumor types indigenous to DBA/212 inbred strain (an epithelial cell, slower growing, and a spindle cell, faster growing) have relatively low initial O.D. (520 mμ) per mg protein and a very low rate of mitochondrial swelling. On the other hand, mitochondria from liver from the same strain of mice exhibit a higher initial O.D. per mg protein and have a high rate of swelling in vitro. “Aged” liver mitochondria have a much lower initial specific O.D. and also swell at a very low rate. Thus, it is proposed that the initial O.D. of isolated mitochondria and its rate of swelling under similar conditions of isolation, resuspension, and incubation is indicative of the inherent quality and integrity of the mitochondrial fraction. Certain conditions of pre-treatment and some specific additives increased mitochondrial swelling of both tumor types, indicating that the mitochondrial integrity of the tumors is at some intermediate state with respect to that of liver mitochondria.