Figure 7. Rapamycin causes a reversible effect on spermatogenesis. All panels show samples from adult males injected with vehicle control (ctrl-rec, n=3) or rapamycin for 3 weeks (rapa-rec, n=3), followed by a recovery period of 2-months. (a) Gross testis morphology. (b-d) Testis mass (b), sperm count (c), and sperm motility (d). Data represent the mean ±SD (NS, not significant, **P<0.01, Student’s t test). (e-h) Testis histology reveals full spectrum of spermatogenesis at 2 months after rapamycin treatment cessation. (i) Western blot analysis of phosphorylation of mTORC1 and mTORC2 substrates.