PLURIHORMONAL CELLS OF ANTERIOR PITUITARY. NEW FEATURES TO OPTIMIZE MOLECULAR DIAGNOSIS OF NEUROENDOCRINE TUMORS

L.B. Mitrofanova(1), P.V. Konovalov(1), Yu. S. Krylova(2), V.O. Polyakova(2,3), I.M. Kvetnoy(2, 3)
1-Federal Almazov North-West Medical Research Centre, Akkuratova str., 2, Saint-Petersburg, Russian Federation, 197341;
2-D.O. Ott Research Institute of Obstetrics, Gynecology and Reproductology,
Mendeleevskaya line, 3, Saint-Petersburg, Russian Federation, 199034
3-Saint-Petersburg State University, 7–9 University embankment, Saint-Petersburg, 199034, Russian Federation
E-mail: lubamitr@yandex.ru

Introduction. Multihormonality is an ability of pituitary cells to produce more than one hormone. A great number of adenomas are multihormonal in the actual practice. We hypothesize cells of a normal pituitary gland to secret several hormones simultaneously. Objective. To investigate the co-expression of hormones by cells of the normal anterior pituitary of adult humans in autopsy material Materials and methods. We studied 10 normal pituitary glands from 4 females and 6 males. Double staining immunohistochemistry using 11 hormone combinations was performed in all the cases. Laser Confocal Scanning Microscopy with a mixture of primary antibodies was performed in 2 cases. Results. We found out same cells of the normal adult human anterior pituitary to be able to co-express PRL with ACTH, TSH, FSH, LH; GH with ACTH, TSH, FSH, LH, and TSH with ACTH, FSH, LH. The comparison of average coefficients of the co-expression of PRL, GH and TSH with other hormones showed the TSH co-expression coefficient to be significantly lower (9,5±6,9%; 9,6±7,8% and 1,0±1,3% correspondingly). Conclusion. Multihormonality of normal anterior pituitary is an actually existing phenomenon. Identification of different hormones in tissue samplesenables to optimize diagnosis and treatment of neuroendocrine tumours.
Keywords: 
multihormonal pituitary cells, confocal microscopy and immunohistochemistry