Transplantable, STH-producing and diabetogenic pituitary adenoma of the BD IX-strain of rats.

A chromophobic pituitary adenoma induced on BD IX-rats has been grafted on animals of the same strain. The transplanted tumour takes in 90-100%; it grows at a slow rate (in 7 months after grafting a weight of 7-20 g is attained). Tumour-bearing animals display gigantism and hypertrophy of adrenals; moreover, in 33% of cases, diabetes is observed. With non-diabetic animals, splenomegaly and marked leukocytosis are observed; immature white and red cells are present in the peripheral blood. Spontaneous regression of the tumour never occurs. After surgical removal, tumour regrowth and the formation of metastases are observed. Diabetes is characterised by pronounced hyperglycaemia, glucosuria, polyphagia and polydipsia. Histochemically, insulin cannot be detected in pancreas. Splenomegaly is never observed in diabetic animals. Transplanted adenoma frequently tends to stop growing. No recurrence is observable after extirpation. Spontaneous regression of the tumour sometimes occurs. Gigantism, hypertrophy of adrenals and diabetes are considered as consequences of growth hormone- and ACTH-secretion of the transplanted adenoma. At present the tumour is running in the 8th passage. It did not change its characteristics over a period of 5 years.