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<article article-type="research-article" dtd-version="1.3" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xml:lang="ru"><front><journal-meta><journal-id journal-id-type="publisher-id">medlit</journal-id><journal-title-group><journal-title xml:lang="ru">Гигиена и санитария</journal-title><trans-title-group xml:lang="en"><trans-title>Hygiene and Sanitation</trans-title></trans-title-group></journal-title-group><issn pub-type="ppub">0016-9900</issn><issn pub-type="epub">2412-0650</issn><publisher><publisher-name>Federal Scientific Center of Hygiene named after F.F. Erisman</publisher-name></publisher></journal-meta><article-meta><article-id pub-id-type="doi">10.47470/0016-9900-2025-104-10-1499-1503</article-id><article-id custom-type="edn" pub-id-type="custom">gshgoz</article-id><article-id custom-type="elpub" pub-id-type="custom">medlit-5299</article-id><article-categories><subj-group subj-group-type="heading"><subject>Research Article</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="ru"><subject>РАДИАЦИОННАЯ ГИГИЕНА</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="en"><subject>RADIATION HYGIENE</subject></subj-group></article-categories><title-group><article-title>Оценка репродуктивной функции самцов лабораторных животных при радиационном и химическом воздействии в малых дозах</article-title><trans-title-group xml:lang="en"><trans-title>Evaluation of reproductive function of male laboratory animals under radiation and chemical exposure in small doses</trans-title></trans-title-group></title-group><contrib-group><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0001-7579-5440</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Мамина</surname><given-names>Вера Павловна</given-names></name><name name-style="western" xml:lang="en"><surname>Mamina</surname><given-names>Vera P.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Канд. биол. наук, ст. науч. сотр. ИЭРиЖ УрО РАН, 620144, Екатеринбург, Россия</p><p>e-mail: mamina@ipae.uran.ru</p></bio><bio xml:lang="en"><p>PhD (Biology), senior researcher, Institute of Plant and Animal Ecology, Ural Department of the Russian Academy of Sciences, Yekaterinburg, 620144, Russian Federation</p><p>e-mail: mamina@ipae.uran.ru</p></bio><email xlink:type="simple">mamina@ipae.uran.ru</email><xref ref-type="aff" rid="aff-1"/></contrib></contrib-group><aff-alternatives id="aff-1"><aff xml:lang="ru"><institution>ФГБУН «Институт экологии растений и животных» Уральского отделения Российской академии наук</institution><country>Россия</country></aff><aff xml:lang="en"><institution>Institute of Plant and Animal Ecology, Ural Branch of the Russian Academy of Sciences</institution><country>Russian Federation</country></aff></aff-alternatives><pub-date pub-type="collection"><year>2025</year></pub-date><pub-date pub-type="epub"><day>19</day><month>12</month><year>2025</year></pub-date><volume>104</volume><issue>11</issue><fpage>1499</fpage><lpage>1503</lpage><permissions><copyright-statement>Copyright &amp;#x00A9; Мамина В.П., 2025</copyright-statement><copyright-year>2025</copyright-year><copyright-holder xml:lang="ru">Мамина В.П.</copyright-holder><copyright-holder xml:lang="en">Mamina V.P.</copyright-holder><license xml:lang="ru" license-type="creative-commons-attribution" xlink:href="https://creativecommons.org/licenses/by/4.0/" xlink:type="simple"><license-p>Данная работа распространяется под лицензией Creative Commons Attribution 4.0.</license-p></license><license xml:lang="en" license-type="creative-commons-attribution" xlink:href="https://creativecommons.org/licenses/by/4.0/" xlink:type="simple"><license-p>This work is licensed under a Creative Commons Attribution 4.0 License.</license-p></license></permissions><self-uri xlink:href="https://www.rjhas.ru/jour/article/view/5299">https://www.rjhas.ru/jour/article/view/5299</self-uri><abstract><sec><title>Введение</title><p>Введение. В связи с ростом идиопатического мужского бесплодия проблема воздействия химических и физических факторов на репродуктивную функцию мужчин сохраняет актуальность. Особого внимания заслуживают исследования о влиянии облучения и шестивалентного хрома на фертильность самцов в малых дозах. Публикации, касающиеся гонадотоксичности и эмбриотоксичности при воздействии этих факторов в малых дозах, предлагают противоречивые выводы.</p></sec><sec><title>Материалы и методы</title><p>Материалы и методы. Экспериментальное исследование проведено на половозрелых мышах линии BALB/c и крысах разведения Вистар обоих полов (всего 189 животных). Животные были разделены на группы в соответствии с получаемыми дозами обучения и бихромата калия. Мыши: группа 1 – контрольная, группа 2 – самцы, получившие дозу 0,25 Гр, группа 3 – получившие дозу 0,5 Гр. Крысы: группа 1 – контрольная, группа 2 – самцы, получавшие бихромат калия (K2Cr2O7) в дозе 0,028 мг/кг, группа 3 – получавшие K2Cr2O7 в дозе 0,28 мг/кг в течение 48 дней. В мазках из клеточного гомогената семенников оценивали сперматогенез. Для анализа эмбриональных потерь подопытных животных спаривали с интактными самками.</p></sec><sec><title>Результаты</title><p>Результаты. При анализе семенников у животных после облучения и хромовой интоксикации определили снижение индекса релаксации на 20%, увеличение многоядерных клеток на 40% (доза 0,5 Гр) и 25% (доза 0,28 мг/кг), рост аберрантных половых клеток в 1,5–2 раза (доза 0,028 мг/кг и 0,5 Гр соответственно) и увеличение почти в 2 раза числа сперматид с микроядрами. Возрастает число сперматозоидов с аномальной головкой: при облучении – на 15–20%, при хромовой интоксикации – в 1,5–2 раза. Спаривание подопытных самцов с интактными самками показало повышение общей эмбриональной смертности плодов в 1,5–2 раза при хромовой интоксикации.</p></sec><sec><title>Ограничения исследования</title><p>Ограничения исследования. Ограничения исследования заключаются в оценке нарушений сперматогенеза без проведения долгосрочных исследований, которые бы позволили определить прогностическую значимость используемых показателей в отношении риска действия облучения и ксенобиотиков в малых дозах на репродуктивную функцию.</p></sec><sec><title>Заключение</title><p>Заключение. Впервые на основе количественных, морфологических показателей установлены степень нарушения сперматогенеза и уровень эмбриональных потерь при облучении и хромовой интоксикации в низких дозах. Наиболее выраженное нарушение сперматогенеза при хромовой интоксикации приводит к более высокому уровню эмбриональной смертности.</p><p>Соблюдение этических стандартов. Экспериментальное исследование было одобрено комиссией по биоэтике ИЭРиЖ УрО РАН (протокол № 13 от 12.03.2025 г.).</p></sec><sec><title>Конфликт интересов</title><p>Конфликт интересов. Автор декларирует отсутствие явных и потенциальных конфликтов интересов в связи с публикацией данной статьи.</p></sec><sec><title>Финансирование</title><p>Финансирование. Исследование выполнено в рамках государственного задания Института экологии растений и животных Уральского отделения РАН (№ 122021000085–1).</p></sec><sec><title>Поступила</title><p>Поступила: 28.04.2025 / Принята к печати: 26.06.2025 / Опубликована: 19.12.2025</p></sec></abstract><trans-abstract xml:lang="en"><sec><title>Introduction</title><p>Introduction.Today, due to the growth of idiopathic male infertility, the problem of the impact of chemical and physical factors on the reproductive function in men remains very relevant.Studies on the effect of radiation and hexavalent chromium on male fertility in small doses deserve special attention.Literature data on gonadotoxicity and embryotoxicity under exposure to factors in small doses are very contradictory.</p></sec><sec><title>Materials and methods</title><p>Materials and methods. The experimental study was conducted on sexually mature BALB/c mice and Wistar rats of both sexes (a total of 189 animals). The animals were divided into groups according to the received dose of training and potassium dichromate. In mice, group 1 was a control, group 2 consisted of males who received a dose of 0.25 Gy, and group 3 received a dose of 0.5 Gy. In rats, group 1 was a control, group 2 consisted of males who received potassium dichromate (K2Cr2O7) at a dose of 0.028 mg/kg, and group 3 – at a dose of 0.28 mg/kg for 48 days. The state of spermatogenesis was assessed in smears from testicular cell homogenate. To analyze embryonic losses, experimental animals were mated with intact females.</p></sec><sec><title>Results</title><p>Results. Analysis of the testicles of animals after irradiation and chromium intoxication revealed the following: a 20% decrease in the relaxation index, an increase in multinucleated cells by 40% (dose 0.5 Gy) and 25% (dose 0.28 mg/kg), in aberrant germ cells by 1.5–2 times (dose 0.028 mg/kg and 0.5 Gy, respectively), and an almost 2-fold increase in the number of spermatids with micronuclei. The number of spermatozoa with abnormal heads increases: by 15–20% with irradiation and by 1.5–2 times with chromium intoxication. Mating of experimental males with intact females indicates an increase in the overall embryonic mortality in fetuses by 1.5–2 times with chromium intoxication.</p></sec><sec><title>Limitations</title><p>Limitations. In the study, when using the quantitative cytological express method in assessing spermatogenesis disorders under the influence of radiation and xenobiotics in small doses, there are no data on remote effects (90–120 days), which would allow determining the prognostic significance of these indicators in solving reproductive problems.</p></sec><sec><title>Conclusions</title><p>Conclusions. For the first time, based on quantitative, morphological indicators, the degree of spermatogenesis impairment and the level of embryonic losses during irradiation and chromium intoxication in low doses were shown. The most pronounced degree of spermatogenesis impairment during chromium intoxication leads to a higher level of embryonic mortality.</p><p>Compliance with ethical standards. The experimental study was approved by the Bioethics Committee of the Institute of Plant and Animal Ecology of the Ural Branch of the Russian Academy of Sciences (protocol No. 13 dated 03/12/2025).</p></sec><sec><title>Conflict of interest</title><p>Conflict of interest. The authors declare no conflict of interest.</p></sec><sec><title>Funding</title><p>Funding. The study was carried out within the framework of State Assignment to Institute of Plant and Animal Ecology (No. 122021000085-1).</p></sec><sec><title>Received</title><p>Received: April 28, 2025 / Accepted: June 26, 2025 / Published: December 19, 2025</p></sec></trans-abstract><kwd-group xml:lang="ru"><kwd>сперматогенез</kwd><kwd>сперматогенные клетки</kwd><kwd>сперматозоиды</kwd><kwd>эмбриональная смертность</kwd><kwd>облучение</kwd><kwd>хромовая интоксикация</kwd></kwd-group><kwd-group xml:lang="en"><kwd>spermatogenesis</kwd><kwd>spermatogenic cells</kwd><kwd>spermatozoa</kwd><kwd>embryonic mortality</kwd><kwd>radiation exposure</kwd><kwd>chromium intoxication</kwd></kwd-group></article-meta></front><back><ref-list><title>References</title><ref id="cit1"><label>1</label><citation-alternatives><mixed-citation xml:lang="ru">Kesari K.K., Agarwal A., Henkel R. Radiations and male fertility. Reprod. Biol. 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