Hydrolases that produce toxic effects

SNAKE VENOM ENZYMES HYDROLASES THAT PRODUCE TOXIC EFFECTS... 

Excessive retinol intake by animals and humans produces distinct toxic manifestations, as discussed in other chapters (Chapter 6, Vol. 1 Chapter 13, Vol. 2). Considerable information is available about the mechanism of the toxic effects of vitamin A on tissues..Studies both in vivo and in vitro have shown that excess retinol results in increased lability of biological membranes (Roels et al., 1969 Fell, 1970). This effect of retinol is believed to be due to its surface-active membranolytic properties (Bangham et al., 1964). In particular, excess retinol has been shown to lead to increased synthesis and release of lysosomal enzymes, and these hydrolases have been shown to be critically involved in the effects of vitamin A on cartilage and limb-bone rudiments (Fell, 1970 Fell and Dingle, 1963 Dingle e/a/., 1971). 

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