Морфологія (Aug 2018)
Lectin histochemistry and morphometric characteristics of adrenal glands of the rats progeny developing under maternal hypo- and hyperthyroidism.
Abstract
Background. Thyroid gland displays strong impact on most organ systems of the body. The aim of present investigation was to study the influences of experimental hypo- and hyperthyroidism of maternal organism on the carbohydrate determinants and morphometric parameters of progeny adrenal glands. Methods. Maternal hypothyroidism was induced by supplementation of daily food allowance of experimental rats with 10 mg/kg of antithyroid drug mercazolil for two weeks before pregnancy, during whole gestational period and through 40 days of progeny’s postnatal life. Hyperthyroidism was induced according to similar protocol by food supplementation with 100 µg/kg of L-thyroxin. Adrenal glands of prenatal day 20th fetuses, postnatal days 1st, 10th, 40th offsprings, and of adult rats with induced hypo- or hyperthyroidism were subjected to histochemistry investigation using PNA lectin with subsequent morphometric studies. Results. On the prenatal day 20th PNA intensely labeled microcirculatory bed. Under maternal hypothyroidism it was detected enhanced reactivity of adrenal parenchima, while hyperthyroidism induced opposite effect. These trends apparently encompass delayed adrenal maturation under hypothyroidism and its acceleration under hyperthyroidism. On postnatal day 1st and henceforth chromaffin cells exposed strong lectin reactivity, while adrenocorticocytes were completely non-reactive. Hypothyroidism was accompanied with vasodilatation and caused reduced lectin binding. On postnatal day 40th and in adult rats differences in lectin labeling of control and experimental group adrenals were less prominent; medullary epinephrocytes exposed strong PNA-reactive cytoplasmic granularity, while norepinephrocytes were only slightly positive. Morphometric studies revealed that both hypo- and hyperthyroidism were accompanied with significantly decreased size of adrenocorticocytes with simultaneous enhancement of nuclear-cytoplasmic index, prominent rearrangement of adrenal cotical zonation. In particular, hyperthyroidism induced as much as 50% of zona fasciculata and almost 100% of zona reticularis thickening in comparison with control group rats. Conclusion. Our investigation revealed significant influences of maternal hypo- and hyperthyroidism on morphogenesis, micromorphological and metabolic characteristics of progeny adrenal glands; hyperthyroidism caused more pronounced alterations compared to hypothyroidism. PNA can be recommended as a selective histochemical marker of rat adrenal medulla beginning from postnatal day 10 and henceforth.
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