1. Experimental systems are described for studying the interaction of compounds with various species of trichomonad. In vitro systems have been used to study the effects of compounds on trichomonads growing in culture and to determine the speed of action of compounds on non-dividing populations. In vivo experiments have utilized vaginal infections in hamsters and subcutaneous, intraperitoneal, intra-muscular and caecal infections in mice. In vitro assays have also been carried out on serum and urine obtained from non-infected rats or monkeys dosed with compounds showing in vitro activity.
2. The types of activity which can be obtained experimentally are illustrated by reference to a number of local remedies already available and to representatives of a number of chemical types, notably acridines, quinoxaline N-oxides, anthrapyrimidines, nitrofurans, thiazoles, imidazoles and pyrazoles.
We thank Dr R. F. Jennison and Mr H. Francis for clinical trial results, Drs J. K. Landquist, G. V. McHattie and D. Richardson for synthesis of some of the compounds mentioned, Dr G. E. Paget for toxicity data, Dr W. M. Duncan for data on the metabolism of 5667, Dr J. M. Pryce for pK determinations and Mrs M. Ryley, P. Ward, A. Fletcher, D. Wood and Miss V. Rowe for technical assistance at various stages in the work.