The examination of the influence of combined iodine and copper deficit on the structural and func- tional features of hypothalamic-pituitary-thyroid system was the aim of the research. The research has been car- ried out on 60 rats, which were divided into two research groups: rats with the hypofunction of thyroid gland (HTG) in conditions of iodine deprivation (HTGI) and in conditions of combined iodine and copper deficit (HTGI+Cu). HTG was modeled by adding drug merkazolil to drinking water (7,5 mg/100g of body weight, during 14 days) and by keeping animals on based iodine deficient diet. Copper deficit was modeled by adding d-penicillamine to drinking water (100mg/100g of body weight, during 21 day). For comparison analogical indexes were determined in 30 in- tact animals (control group). In the result of the experiment the changes of thyroid homeostasis were determined: in animals with HTGI – significant decreasing (on 63,62 %) the content of fT3, and in animals of the 2-nd research group – the content of fT3 – on 52,41 % and fT4 – on 64,70 % on the phone of increasing the content of thyroid stimu- lating hormone of blood serum in 2,29 times in comparison with the analogical indexes in animals of the control group. HTG had lead to the changes of cerebrum structure. So, in rats with HTGI edema, deformation of neuron’s bodies, the changes of nucleus shape were observed. In the case of HTGI+Cu the structures of hypothalamus were more changed: blood vessels with increased blood supply, with compact arrangement of red blood cells, with the phenomena of compression. The square of neuron’s profile has become 2,43 times bigger and its perimeter – 1,77 times bigger than initial level. The nucleus of neurons are deformed with enlightened caryoplasm. The square of nucleus profile has become on 27,61 % bigger than analogical index in rats with HTGI. In such experimental conditions the disruption of endocrinocytes bands with enlightened cytoplasm, eccentrically displaced nucleus, abnormal blood supply vessels were observed in adenohypophysis. In animals with HTGI the follicles have different sizes, are deformed often, have bright pink color, the square of colloid has become 2,0 times bigger than analogi- cal indexes in intact animals. The square of thyrocytes nucleus has become on 17,52 % less than correspondent indexes in animals of control group. The follicles with desquamated epithelium are observed. In the conditions of HTGI+Cu the thyroid gland (TG) has become more changed. The structure of TG has become mosaic. The follicles are covered by flattened epithelium. The square of follicles has become on 26,87 % bigger than correspondent indexes in rats with HTGI. The internal perimeter and diameter of such follicles significantly higher than the data in intact rats and animals of the 1-st research: at 1,29 times, p < 0,001 and 1,13 times, p < 0,001 respectively. The thyrocytes of not big, deformed follicles are flattened also, the square of their nucleus on 26,25 % lower than the same indexes in animals of the 1-st research group. All follicles contain saturated colloid, the square of which has become on 30. 55 % bigger than the analogical indexes in rats with HTGI. The decreasing of the height and the square of follicles epithelium on 41,42 % and 48,63 % respectively to analogical indexes in animals with HTGI was observed. The de- creasing of functional activity of TG on the background of microelement imbalance is followed by the development of polymorphic dystrophic disturbances of hypothalamic-pituitary system. They combined with structural changes of thyrocytes and with the degree of thyroid dyshomeostasis. Combined iodine and copper deficit is followed by more severe structural and functional changes of hypothalamic-pituitary-thyroid axes.
hypofunction of thyroid gland, iodine deficit, copper deficit, hypothalamic-pituitary system
«Bulletin of problems biology and medicine» Issue 4 part 1 (113), 2014 year, 88-93 pages, index UDK 616. 391+546. 15+546. 56+611. 814+616. 432
