The Interaction between Metals and Chelating Agents in Mammalian Spermatozoa

Several studies have been made on the bacteriostatic and fungicidal properties of oxine (8-hydroxyquinoline) and other chelating agents, and it has been suggested that they might act, in part at least, by depriving cells of essential trace metals (Albert, 1951; Martell & Calvin, 1952). In an attempt to determine the trace element requirements of mammalian spermatozoa, White (1955) investigated the effect of several chelating agents on motility. A number were found to be toxic to ram, bull, rabbit and human spermatozoa. In fact some (e.g. sodium diethyl dithiocarbamate, i-nitroso-2naphthol and ethyl potassium xanthate) were much more spermicidal than oxine, which has long been used as a chemical contraceptive in the form of Chinasol. Tests with bull semen showed that cobalt reduced the toxicity of sodium diethyldithiocarbamate, nitrosonaphthol and o-phenanthroline. Other mixtures of heavy metals and chelating agents were, however, more toxic than the chelating agents alone. Further studies on the interaction between metals and chelating agents in bull, ram, rabbit and human spermatozoa are presented in this paper.