Putative odorant receptors, GRK3, and β-arrestin2 colocalize in late spermatids of rat testis by immunohistochemistry
(A) A hematoxylin and eosin (H&E) stain of the rat testis reveals seminiferous tubule cross sections representing each of the 14 stages of the epithelial cycle. Shown here is a tubule cross section that contains cells representative of the differentiation continuum including spermatogonia (SG), spermatocyte (SC), early spermatid (EST), and late spermatid (LST); 200X. (B) Preincubation of the OD1 antibody with pure peptide produced no staining of the testis; 200×. (C) The seminiferous tubule cross sections containing elongating spermatids stain intensely with the OD1 antibody (arrows), while tubules at earlier stages in the spermatogenic cycle are negative (arrowheads); 100×. (D) The OD1 antibody (1:250) stains adluminal late spermatids; 200×. (E and F) β-Arrestin2 and GRK3 antibodies (1:50) similarly stain late spermatids; 200×. The antibodies do not stain spermatogonia, spermatocytes, early spermatids, Sertoli cells, or Leydig cells.