Immunoreactive neurotensin and somatostatin in the chicken thymus. A chemical and histochemical study.

Two distinct populations of endocrine cells in the chicken thymus display neurotensin and somatostatin immunoreactivity, respectively. Both cell types are few in number at hatching but proliferate rapidly during the first week. The neurotensin cells are 'Grimelius-positive' and 'Hellerström-Hellman-negative'. The somatostatin cells are 'Grimelius-negative' and 'Hellerström-Hellman-positive'. Both cell populations are non-argentaffin. The somatostatin-like material extracted from chicken thymus behaves immunochemically and chromatographically similar to synthetic ovine somatostatin, while the neurotensin-like material, from the thymus as well as from the gut, differs from synthetic bovine neurotensin in that it appears larger in size and more basic.