A modified method for collection of rete testis fluid from the rat

Collection of rete testis fluid (RTF) from rats and monkeys has previously involved ligation of the efferent ducts (EDL) for 18–27 h before transcapsular cannulation of the swollen intratesticular rete (Tuck et al. 1970; Waites & Einer-Jensen 1974). Our concern for possible contamination of such samples by lymph or capillary exudate prompted us to adopt a modified microcannulation procedure in order to reduce such contamination. Other methods for collecting RTF include cannulating ‘efferent ducts’ with or without previous EDL, respectively, in rabbits (Cooper et al. 1976) and rats (Free & Jaffe 1979). The latter cannulation technique proved difficult to repeat, and the volume of RTF collected was insufficient for analysis. This paper describes a method for routine collection of RTF from anaesthetised rats following cannulation of the extra-testicular rete testis after efferent duct ligation.