nefrНефрологияNephrology (Saint-Petersburg)1561-62742541-9439Pavlov First Saint-Petersburg State Medical University10.24884/1561-6274-2005-9-3-81-87nefr-686Research ArticleЭКСПЕРИМЕНТАЛЬНЫЕ ИССЛЕДОВАНИЯГОМОЦИСТЕИН ВЫЗЫВАЕТ ПОВРЕЖДЕНИЯ НЕ ТОЛЬКО КЛУБОЧКОВОГО, НО И КАНАЛЬЦЕВОГО ОТДЕЛА НЕФРОНА (ЭКСПЕРИМЕНТАЛЬНОЕ ИССЛЕДОВАНИЕ)HOMOCYSTEIN CAUSES LESIONS OF NOT ONLY GLOMERULAR BUT ALSO TUBULAR PART OF THE NEPHRON (EXPERIMENTAL STUDY)СмирновА. В.SmirnovA. V.

Научно-исследовательский центр, кафедра патологической физиологии

ДобронравовВ. А.DobronravovV. A.

Научно-исследовательский центр, кафедра патологической физиологии

НеворотинА. И.NevorotinA. I.

Научно-исследовательский центр, кафедра патологической физиологии

ХохловС. Е.KhokhlovS. E.

Научно-исследовательский центр, кафедра патологической физиологии

СиповскийВ. Г.SipovskyV. G.

Научно-исследовательский центр, кафедра патологической физиологии

БарабановаВ. В.BarabanovaV. V.

Научно-исследовательский центр, кафедра патологической физиологии

ЧефуС. Г.ChefuS. G.

Научно-исследовательский центр, кафедра патологической физиологии

ЖлобаА. А.ZhlobaA. A.

Научно-исследовательский центр, кафедра патологической физиологии

БлашкоЭ. Л.BlashkoE. L.

Научно-исследовательский центр, кафедра патологической физиологии

Научно-исследовательский институт нефрологии, Cанкт-Петербургский государственный медицинский университет имени акад. И.П. ПавловаRussian Federation200510032005938187Copyright © Смирнов А.В., Добронравов В.А., Неворотин А.И., Хохлов С.Е., Сиповский В.Г., Барабанова В.В., Чефу С.Г., Жлоба А.А., Блашко Э.Л., 20052005Смирнов А.В., Добронравов В.А., Неворотин А.И., Хохлов С.Е., Сиповский В.Г., Барабанова В.В., Чефу С.Г., Жлоба А.А., Блашко Э.Л.Smirnov A.V., Dobronravov V.A., Nevorotin A.I., Khokhlov S.E., Sipovsky V.G., Barabanova V.V., Chefu S.G., Zhloba A.A., Blashko E.L.Данная работа распространяется под лицензией Creative Commons Attribution 4.0.This work is licensed under a Creative Commons Attribution 4.0 License.https://journal.nephrolog.ru/jour/article/view/686

ЦЕЛЬЮ ИССЛЕДОВАНИЯ было выявление функциональных и структурных последствий экспериментальной гипергомо цистеинемии в почках крыс. МАТЕРИАЛ И МЕТОДЫ. Взрослым белым крысам линии Вистар в течение 3 недель паренте рально вводили гомоцистеин (ГЦ; 13.4 мг/кг) для оценки влияния экспериментальной гипергомоцистеинемии (ГГЦ) на мочевую экскрецию альбумина (МЭА), клиренс креатинина (CCr), а также на структуры клубочков и проксимальных каналь цев (ПК) на светооптическом и электронномикроскопическим уровнях. РЕЗУЛЬТАТЫ. Развитие умеренной ГГЦ у экспери ментальных животных приводило к достоверному увеличению МЭА без достоверного изменения CCr, что сопровождалось умеренной мезангиальной пролиферацией, гиперплазией гломерулярной базальной мембраны, заметным увеличением числа больших апикальных вакуолей и вторичных лизосом, а также очаговой утратой щеточной каймы в отдельных клетках ПК. Кроме того, в ПК было отмечено увеличение количества аутофагосом, наряду с наличием эпителиальных клеток с дезорганизованными участками базальной цитоплазмы. ЗАКЛЮЧЕНИЕ. Полученные данные следует рассматривать как прямое доказательство повреждающего действия ГГЦ на клубочки и клетки ПК.

THE AIM of the investigation was to find out the functional and structural consequences of experimental hyperhomocysteinemia (hHcy) in the rats’ kidneys. MATERIAL AND METHODS. Adult albino Wistar rats were exposed to daily parenteral homocysteine for three weeks in order to evaluate the influence of experimental hHcy on urinary albumine excretion (UAE), plasma creatinine concentration and creatinine clearance (CCr) as well as on the alterations of the glomerular and proximal tubular (PT) structures at the light and electron microscopy levels. RESULTS. The development of mild hHcy in experimental animals resulted in significantly increased UAE without a significant CCr change that was accompanied by moderate focal mesangial and endothelial cell proliferation, glomerular basement membrane hyperplasia, appreciably increased number of large apical vacuoles and secondary lysosomes, and focal loss of the brush border in certain PT cells. In addition, an increased number of autophagic vacuoles along with the epithelial cells with disorganized loci of the basal cytoplasm was noted. CONCLUSION. The data obtained are considered to be a direct evidence of the impairing effect of hHcy on the glomeruli and PT cells.

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The authors declare that there are no conflicts of interest present.