Effect of Alacreatine on the Rat

Abstract

IN an earlier communication we reported that rats fed a diet containing 2 per cent of DL-α-guanidinopropionic acid (alacreatine) develop weakness during a 6-week period¹. In subsequent work we have been unable to demonstrate either a defect in creatine metabolism in these animals or improvement of the weakness by creatine administration. Because of an odour which suggested the presence of a sulphur-containing compound in the alacreatine preparation further experiments were done with highly purified odourless alacreatine. None of the animals receiving the purified alacreatine became weak. It thus appears that the weakness was not caused by alacreatine, but by an impurity. The impurity has not been identified. However, various isothiourea and guanidine derivatives are known to be toxic in acute dose² and such compounds could have been present in the original preparations of alacreatine.