CXCL14 immunoreactivity is localized in pituitary GH-producing cells and in median eminence somatostatin-containing fibres of the Japanese quail (Coturnix japonica)

This is the first study to examine the distribution of a chemokine CXCL14-like peptide in the pituitary and hypothalamus of an avian species, the Japanese quail (Coturnix japonica). We employed immunohistochemical techniques using a specific anti-human CXCL14 antibody. CXCL14-immunoreactive cells were detected in the caudal lobe of the pars distalis. CXCL14-immunoreactive puncta were densely distributed in the external layer and sparsely distributed in the internal layer of the median eminence. CXCL14 staining was absent after pre-absorption of the antibody with recombinant human CXCL14. All CXCL14-immunoreactive cells corresponded to growth hormone (GH)-producing cells in the caudal lobe. In addition, the majority of CXCL14-immunoreactive puncta in the median eminence corresponded to somatostatin-containing fibres. CXCL14 secreted from GH-producing cells and somatostatin-containing fibres may act as an inhibitor of GH release via an autocrine mechanism and neuroendocrine signalling, respectively.