RESUMEN
<p><b>OBJECTIVE</b>To explore genital toxicity of depleted uranium (DU) by studying the changes of inducible nitric oxide synthase (iNOS) in the testis of rats instilled with DU particles.</p><p><b>METHODS</b>Wistar rats were exposed to DU by means of different dosages of DU particles intratracheal instillation. The samples of the testis were collected 3 months later, and iNOS mRNA was determined by reverse-transcription PCR (RT-PCR). Semiquantitative analysis of the RT-PCR products was made with a transilluminator.</p><p><b>RESULTS</b>iNOS mRNA was not observed in the control group. Compared with the control, there were significant increases of OD in the PCR products of all the DU groups (P < 0. 05 ); OD rose gradually from the DU 1 mg group to the DU 3 mg group, peaked in the latter, and subsided significantly in the DU 5 mg group (P < 0.05).</p><p><b>CONCLUSION</b>Intratracheal instilled DU particles play a key role in iNOS mRNA expression of the rat testis. The iNOS mRNA expression will weaken when the DU dosage reaches a certain level, which may attribute to the complex of DU's chemical toxicity and radiation effects.</p>