Morphology of rat testis preserved in three different fixatives

Abstract

Histopathological examination of testes is important in assessing spermatogenesis and testicular function. Modified Davidson’s fluid (mDF) has been proposed as a superior substitute for Bouin’s fluid (BF) for fixation of adult animal testes. Besides, 4% paraformaldehyde (PFA) has been commonly used to fix testes with convenience. We compared the morphology of the rat testis fixed in 4% PFA, mDF, or BF using hematoxylin and eosin (HE)-stained sections. Fixation in 4% PFA resulted in obvious tissue shrinkage artifacts, especially between seminiferous epithelium cells. Shrinkage artifacts were also observed in the central area of the testes fixed in BF. Use of mDF did not cause shrinkage artifacts between seminiferous tubules, though a small amount can be observed in seminiferous tubules between germ cells. Clarity of nuclear detail in testes fixed in mDF and BF is better compared to 4% PFA. Our study demonstrated that fixation in mDF provided better morphologic details in the rat testis as compared with 4% PFA and BF.

Keywords

fixative / testis / HE staining

References

[1] Organization for Economic Co-operationDevelopment. Proposal for updating Guideline 416: Two generation reproduction toxicity study. OECD Guideline for Testing of Chemicals, No. 416, 2001, Paris, OECD, 1-13

[2] LatendresseJ.R., WarbrittionA.R., JonassenH., et al.. Fixation of testes and eyes using a modified Davidson’s fluid: comparison with Bouin’s fluid and conventional Davidson’s fluid. Toxicol Pathol, 2002, 30(4): 524-533

[3] HowroydP., Hoyle-ThackerR., LyghtO., et al.. Morphology of the fetal rat testis preserved in different fixatives. Toxicol Pathol, 2005, 33(2): 300-304

[4] KiernanJ.A.. . Histological and Histochemical Methods: Theory and Practice, 19993rd edOxford, Butterworth-Heinemann Press, 11-35

[5] CreasyD.M., JonassenH.. Histological fixation of testes: Use of Davidson’s fluid as an alternative to Bouin’s fluid. Vet Pathol, 1999, 36: 518