Transcriptomics of immature rat testes from chemically induced hypothyroid rats reveal shared and compound-specific effects

Developmental hypothyroidism can affect testicular growth in rodents and humans. For example, rats exposed perinatally to the antithyroid drug propylthiouracil (PTU), which reduces thyroid hormones (THs) by inhibiting the thyroperoxidase (TPO) enzyme, display reduction in testes size. Similarly, we observed smaller testes in rats exposed perinatally to two other TPO-inhibiting chemicals: the pharmaceutical methimazole (MMI) and the pesticide amitrole (Ami). However, on closer histopathological examination and analysis of serum hormone levels, the effects on the testes were different between the two chemicals (see poster Draskau et al). This suggests different effects beyond hypothyroidism; thus, by further analysis we can start unravelling how hypothyroidism disrupts testis development at the molecular level concomitantly with additional endocrine disrupting effects by environmental chemicals. To investigate the transcriptional profile of rat testicles, we employed bulk-RNA-barcoding and sequencing (BRB-seq) of postnatal rat testicles after perinatal exposure to MMI and amitrole.