Изменение экспрессии хромогранина А в надпочечниках поросят на разные сроки неонатального развития

Abstract

В статье приведены данные о перераспределении клеток, содержащих хромогранин А (ХрА), в различных зонах надпочечника у свиней на разные сроки неонатального развития. Показано, что основная масса ХрА-позитивных клеток сосредоточена в мозговом веществе. Кроме того, одиночные клетки или агрегаты из нескольких ХрА-позитивных клеток наблюдаются в субкапсулярной области коры, а также расположены радиально в виде тяжей, направленных от периферии органа к мозговому веществу. Установлено, что с возрастом у свиней уменьшается площадь поперечного сечения мозгового вещества относительно площади поперечного сечения всего органа, а также уменьшается площадь, занимаемая экстрамедуллярными ХрА-позитивными клетками. _______________________________________________________________________ The article presents data about the redistribution of cells containing chromogranin A (CgA) in various zones of the adrenal gland in pigs for different periods of neonatal development. The adrenal glands were obtained from piglets at 1,7, 14, and 28 days after birth. The expression of CgA was studied by the immunohistochemical staining of cryosections of the adrenal glands. To identify the CgA-positive cells the primary rabbit polyclonal antibodies to CgA (dilution 1:200, Abcam, UK) and goat polyclonal secondary antibodies to rabbit IgG - H&L (AlexaFluor 488, dilution 1:400, Abcam) were used. It was shown that the bulk of the CgA-positive cells is concentrated in the adrenal medulla. In addition, single cells or aggregates of several CgA-positive cells are observed in the subcapsular region of the cortex and also located radially in the form of strands directed from the periphery of the organ to the adrenal medulla. During the entire period of pig neonatal development a change of adrenal cross-sectional area (Sc s ) is observed. At first 24 hours after birth the S of the adrenal glands was 4.5 ± 0.5 mm cs cs 2 . By the 28th day after birth the total S of the organ increases by 3.3 times. Moreover when assessing the comparative area of the adrenal medulla (Sm ) it is noticeable that it decreases from 7th day. At the 1st day of neonatal development Sm constitutes 25% of the total adrenal gland Sc s , on the 7th day it is 18%, on the 14th and 28th - 10 and 13%, respectively. With the morphometric analysis we estimated the comparative area of CgA-positive extramedullary cells. The decrease of this parameteer with age is established. At the 1st day it was 1.1% of the total adrenal Sc s , 7th - 1%, at the 14th - 0.5% and at the 28th - 0.2%. In summary we have shown that anatomical and physiological changes, which touch on the cortex as well as the medulla, occur in the pig adrenal glands during neonatal development. They consist of an increase of cortex Sc s , decrease of medulla Sm , as well as a decrease in the number of extramedullary CgA-positive cells.