Immunohistochemical localization of LH-producing cells in the adenohypophysis of the Japanese quail,Coturnix coturnix japonica

Summary The cells that produce luteinizing hormone (LH) in the adenohypophysis of the Japanese quail were identified immunohistochemically using anti-chicken LH serum and horseradish peroxidase-labeled goat anti-rabbit gamma globulin serum. The LH cells are localized in the caudal lobe of the pars distalis. They are elongate in shape and are polarized toward the sinusoids, especially in their active states. Alterations in size of LH cells are directly related to changes in circulating LH levels as induced by castration or photostimulation. The LH cells identified immunohistochemically were only stained by alcian blue with periodic acid-Schiff (PAS), alcian blue and orange G.PAS-positive gonadotropic cells in the cephalic lobe were stained immunohistochemically only slightly if at all using anti-chicken LH serum and consequently may be FSH producing cells. In the cephalic lobe another type of basophilic cell was stained with alcian blue. These cells were also stained immunohistochemically with anti-chicken LH serum. These cells may possibly be identified as TSH cells due to the characteristics of the antichicken LH serum used in this study which cross react with LH and TSH but only slightly with FSH, and also on the basis of previous light and electron microscopic studies.We express our gratitude to Professors Hideshi Kobayashi and Katsumi Wakabayashi for their valuable guidance during the experiment. We also express our cordial thanks to Professor B.K. Follett for the gift of anti-chicken LH serum and standard LH. This work was supported in part by Grants from Ministry of Education of Japan and from the Ford Foundation.