Структурна організація губних залоз та ланки гемомікроциркуляторного русла новонародженої людини

Abstract

В роботі стереологічний аналіз показав, що губна залоза новонароджених людини утворена чотирма – п’ятьма залозистими дольками, розділеними одна від одної значними за товщиною сполучнотканинними прошарками. Дольки мають різну величину і форму. Їх епітелій представлений кінцевими та вставними відділами, а також системою вивідних проток, які відрізняються одна від одної розмірами зовнішнього діаметру, просвітом, товщиною і клітинним складом стінки. Більшість епітеліальних структур залози новонародженого мають вигляд цілком сформованих. На гістологічних зрізах легко розрізняються всі протоки: внутрішньодолькові, долькові, міждолькові, головну вивідну; В работе стереологический анализ показал, что губная железа новорожденных человека образована четырьмя – пятью железистыми дольками, которые разделены одна от другой значительными по толщине соединительнотканными прослойками. Дольки имеют различную величину и форму. Их епителий представлен концевыми и вставочными отделами, а также системой выводных протоков, которые отличаются один от другого размерами наружного диаметра, просветом, толщиной и клеточным составом стенки. Большинство эпителиальных структур железы новорожденного имеют вид полностью сформированных. На гистологических срезах легко различаются все протоки: внутридольковые, дольковые, междольковые, главный выводной проток; The paper presents the findings of stereologic analysis, showing that human newborn labial gland is formed by four-five glandular lobules, separated by the significant thick connective tissue interlayers. Lobules vary in size and form. Their epithelium is represented by the terminal and intercalated segments, as well as system of excretory ducts, varied in sizes of outer diameter, lumen, thickness and cell content of the wall. The majority of epithelial structures of newborn’s gland look as completely formed ones. All ducts are easily differentiated on histological sections: intralobar, lobar, interlobar, and major excretory. Stromal-parenchymatous index shows the joint ratio of parenchyma and the stroma on different gland levels. Its decline shows lowering of the amount of stroma, which reaches its peak value at the level of the gland’s hilum. The vascular-parenchymatous index in newborns has the maximum value at the level of the gland’s hilum, and while decreasing, reaches its minimum value at the level of single lobule. Such reduction of vascular-parenchymatous index is explained by the formation and branching of periacinous circulatory net around the terminal segments and intercalated ducts, which are being formed in the gland’s lobules, as well as the differentiation of capillaries around the periphery of sublobar units, whereas blood-vascular net has been already formed within the hilum of individual gland and the movement of branching of large ducts. Method of multilayer graphic reconstruction by the series of detailed microphotomaps has found that it is based on the circular anastomosis of arterioles, which provide the delivery and equal distribution of blood among the particles of one or another gland. A similar principle of organization of resistive microvessels allows to allocate formally the particular microvascular moduli in the gland, concentrated in the parenchyma in a way that the blood delivery and its distribution among the glandular tissue is performed on the side of terminal sections, and not on the path of excretory ducts. In the partition of the individual microvascular modulus the precapillary arterioles, starting from the ring arterioles, penetrate deeply into the lobule, running to its central sections, where the axial structures are presented by the intralobar excretory ducts, adjoining with the volume microvessels, i.e., postcapillary and collective venules. It is notable, that such relationship of volume microvessels with intralobar ducts is the most specific and universal feature of the system of structural provision of salivary glands functioning. Layers of sequentially connected microvessels of capillary type are found between the precapillary arterioles and collective venules, which are different from the “regular” blood vessels by the wider lumen and the fact that their wall is formed by the fenestrated endothelium. Due to such microvessels, paths of predominant bloodstream are formed in the salivary glands. «Regular» capillaries, represented in the form of interacinous loops, formed by the intralobar nets, locations of which are specifies by their parallel intercalation relative to the ducts of predominant bloodstream. Such interacinous capillaries are characterized by the narrow lumen, and their wall, in contrast to postcapillary venules, is formed by non- fenestrated endothelium. Therefore, communications, intercalated into blood flow both sequentially and parallel, are presented in the microcirculatory bloodstream of the salivary glands. In this way ducts with parallel blood perfusion have less dissection and, consequently, are to put stronger resistance to blood flow.