Natural and artificial substances present in the environment can affect our health. Testicular toxicants in particular are troublesome, because they disturb gonadal function of males. Translocation of substances into the seminiferous epithelium where sperm production proceeds is restricted due to the blood-testis barrier, but this permeability barrier temporarily disappears under physiological and sub-physiological conditions. This means that any substance could enter the seminiferous epithelium and disturb sperm production. To reduce the risk posed by such toxins, it is important to accurately determine which substances possess the @entity137 . However, existing assay systems are not satisfactory in terms of both accuracy and sensitivity. Here, we report the establishment of such a system. We injected the @entity342 antagonists, @entity12194 and @entity30173 , directly into seminiferous tubules of live @entity19 , which had been treated with @entity1863 for a temporal arrest of spermatogenesis, and the testes were histologically examined to see the effect of the injected materials on spermatogenesis that was in the process of recovery. The injection of either substance brought about a severe impairment of spermatogenesis at an amount over a million times smaller than that used in the previous assay systems where animals are administered with test substances outside of the testis. In contrast, these @entity342 antagonists at the same doses showed lesser effects when intratubularly or intraperitoneally administered into @entity19 that had not been pretreated with @entity1863 . We propose that the method adopted in this study is a novel assay system to identify potential testicular toxicants.

Perturbation of spermatogenesis by @entity342 antagonists directly injected into seminiferous tubules of live XXXX .

@entity137 :: ('MESH:D064420', 'Disease') :: ['toxicity'] @entity19 :: ('10090', 'Species') :: ['mice'] @entity1863 :: ('MESH:D002066', 'Chemical') :: ['busulfan'] @entity12194 :: ('MESH:D005485', 'Chemical') :: ['flutamide'] @entity342 :: ('CHEBI:50113', 'Chemical') :: ['androgen'] @entity30173 :: ('MESH:C025643', 'Chemical') :: ['vinclozolin']
@entity19 :: (10090,Species) :: ['mice']
