ABSTRACT
Cells are composed of a number of organelle compartments that play crucial roles in facilitating metabolic processes essential to cellular viability (Figure 39.1). The effects of many toxic agents on cells are mediated via damage to one or more of these specialized subcellular compartments. Specific organelle systems may become damaged by toxic agents when they perform a primary role in the metabolism of a particular toxicant, when a toxicant is stored intracellularly, or as a result of an inherent sensitivity of some essential biochemical pathways in the organelle to perturbation. In terms of understanding the mechanisms of cellular toxicity, it is clear that evaluation of organelles as basic units of subcellular function may provide useful insights into the basis of toxicant action. It also should be obvious that the ability to detect damage within particular organelle systems depends on the sensitivity and nature of the parameters measured. The following discussion examines some of the current ultrastructural and biochemical methods available for evaluation of specific organelles and reviews some of the ways in which these techniques have aided understanding the mechanisms of toxicity. A critical examination of these techniques is presented to aid the reader in assessing the potential value of a given procedure for delineating information about a specific toxic process.
