Microcalorimetric studies of perchlorate on heat production by hepatocytes and mitochondria isolated from Carassius auratus.

As a new threat to environment all through the world, perchlorate (ClO(4)(-)) was predominantly a thyrotoxin, and its toxic manifestations in non-thyroid were also documented. However, little is known about the effects of ClO(4)(-) on cell and organelle. Therefore, the present study was designed to investigate the effects of ClO(4)(-) on hepatocytes and mitochondria isolated from Carassius auratus from the direct viewpoint of energy by using the microcalorimetric method. The metabolic thermogenic curves of hepatocytes and mitochondria at 25°C were obtained. And the thermokinetic parameters, such as growth rate constant (k), inhibitory ratio (I), maximum thermal power (P(max)) and total thermal effect (Q(total)) have been calculated. The results indicated that the toxicity of ClO(4)(-) on hepatocytes was relevant to the concentration of ClO(4)(-). However, 10-100mgL(-1)ClO(4)(-) stimulated the metabolic activity of mitochondria and the toxicity of ClO(4)(-) on mitochondria only occurrenced when treated with higher concentration of ClO(4)(-). This study shown that mitochondria has a major impact on the metabolic thermogenic of hepatocytes, but not the only factor. Meanwhile, it demonstrated that microcalorimetry was a powerful tool for understanding biological processes and studying on the toxic action of environmental contaminants in cell or subcellular level.