Expression of 11β-hydroxysteroid-dehydrogenase 2 in Sertoli cells of boar testes

11β-Hydroxysteroid-dehydrogenase 2 (11β-HSD2) activity occurs in boar testes but it is not known which cell types express 11β-HSD2 mRNA and protein. Therefore, testes samples were taken from mature boars. For immunocytochemistry and Western blot pig-specific antibodies were raised against a 10-amino acid peptide corresponding to amino acids 391–400 of the coding sequence. Quantitative PCR was performed in testis homogenates and additionally RT-PCR in samples collected by UV-single cell microdissection. Data show that in interstitial tissue 11β-HSD2 is expressed in Leydig cells and additionally in blood capillaries. In tubuli, 11β-HSD2 primarily is formed in Sertoli cells whereas occurrence in spermatogonia could not be definitely proven. Because glucocorticoid receptors were never found in boar Leydig cells, it is concluded that the expression of 11β-HSD2 in several types of cells forms consecutive lines of defense to protect spermatogonia against glucocorticoid-induced apoptosis.