PROLACTIN-SECRETING PITUITARY-ADENOMAS WITH MAMMARY DYSPLASIA IN NEW-ZEALAND WHITE-RABBITS

Citation
Ns. Lipman et al., PROLACTIN-SECRETING PITUITARY-ADENOMAS WITH MAMMARY DYSPLASIA IN NEW-ZEALAND WHITE-RABBITS, Laboratory animal science, 44(2), 1994, pp. 114-120
Citations number
34
Categorie Soggetti
Veterinary Sciences
Journal title
ISSN journal
00236764
Volume
44
Issue
2
Year of publication
1994
Pages
114 - 120
Database
ISI
SICI code
0023-6764(1994)44:2<114:PPWMDI>2.0.ZU;2-0
Abstract
Nine aged (mean age = 3.2 years) nulliparous New Zealand white rabbit does were found to have markedly enlarged teats. The teats were freque ntly engorged with fluid but were not hot and did not cause signs of p ain. The number of affected teats per animal ranged from 1 to 8 (mean = 4). The teats and associated glandular tissue were typically discolo red grey, blue, or greenish black (n = 6). Prolactin concentrations we re evaluated by radioimmunoassay. Serum prolactin concentrations range d from 22.4 ng/ml to 2.21 mu g/ml (mean = 397.3 ng/ml), which was 10 t o 1000-fold greater than normal values in nonpregnant rabbits. Convent ional radiography of the skull of six rabbits did not reveal pituitary enlargement. Necropsy revealed an enlarged pituitary gland and sella turcica in six of nine does. The diaphragma sellae had ruptured in two rabbits. All nine rabbits had pituitary acidophil adenomas. The neopl astic portions of the pituitaries were diffusely immunoreactive when s tained immunohistochemically for prolactin. In contrast, only small cl usters of five to seven cells stained positively in normal pituitaries selected as controls. Histologic examination of the mammary glands re vealed numerous large, dilated cystic spaces containing proteinaceous fluid. Many cysts had numerous papillary epithelial infoldings. The cy stic dilations extended into and included the teat canal producing the gross appearance. Prolactin-secreting acidophil adenomas have not bee n previously reported in the rabbit, and the association with mammary dysplasia is unique.