title: Biosynthesis of thyrotropin-releasing hormone in organ cultures of the guinea pig median eminence.
abstract: Guinea pig median eminence tissue was put into organ culture for periods up to 13 days. The cultured tissue was examined in 3 ways at various ages: a) morphologically, by transmission electron microscopy and light microscopic autoradiography; b) biochemically, by determination of the ability of the cultures to accumulate [3H]L-proline and to incorporate this isotope into [3H]TRH; and c) by bioassay, in which the content of TRH in tissue and culture medium was determined by the ability of extracts of both to release radioimmunoassayable TSH from rat hemi-pituitaries incubated in vitro. It was found that the cultures exhibited a high degree of preservation  of ependymal cell morphology and a sustained ability to accumulate [3H]L-proline over the entire 13-day time course. Neuronal elements showed a progressive degeneration with time in culture, and the ability of the culture to produce [3H]TRH was lost concomitantly with the loss in neuronal integrity.
mesh_terms: D000818:Animals; D001345:Autoradiography; D001681:Biological Assay; D006168:Guinea Pigs; D007030:Hypothalamo-Hypophyseal System / Q000378:metabolism*; D008473:Median Eminence / Q000032:analysis / Q000378:metabolism* / Q000648:ultrastructure; D008854:Microscopy, Electron; D009924:Organ Culture Techniques; D011392:Proline / Q000378:metabolism; D013973:Thyrotropin-Releasing Hormone / Q000032:analysis / Q000096:biosynthesis*
chemical_list: D013973:Thyrotropin-Releasing Hormone; D011392:Proline