TRANSGENIC MODELS OF PITUITARY DISEASES

Transgenic mice are valuable experimental models of human endocrine di seases. Targeted ablation of specific cell lineages or insertion of ge nes coding for releasing factors, hormones, growth factors, and oncoge nes fused with appropriate promoters, or mutated genes, can induce sev eral pituitary disorders. Various hyposecretory and hypersecretory sta tes have been induced, some of them due to functioning pituitary adeno mas. Adenohypophysial changes in such disorders have been thoroughly i nvestigated in many of the transgenic lines. Functioning and silent pi tuitary adenomas resemble those seen in human patients, and are invalu able models of tumorigenesis. The available models have not been suffi ciently exploited and new models are expected in the near future. In t his review, the morphologic changes of the pituitary are described in transgenic mice and, when available, the ultrastructural alterations a re included. (C) 1997 Wiley-Liss, Inc.