Russian Journal of PhysiologyRussian Journal of PhysiologyРоссийский физиологический журнал им. И.М. Сеченова0869-81392658-655XThe Russian Academy of Sciences65162010.31857/S0869813924070091BDKVNMEXPERIMENTAL ARTICLESЭКСПЕРИМЕНТАЛЬНЫЕ СТАТЬИResearch ArticleIntegration of single-photon miniature fluorescence microscopy and electrophysiological recording methods for in vivo studying hippocampal neuronal activityОбъединение методов однофотонной миниатюрной флуоресцентной микроскопии и электрофизиологической регистрации для исследования активности нейронов гиппокампа in vivoErofeevА. I.ЕрофеевА. И.
Russian Federation

Institute of Biomedical Systems and Biotechnology

Институт биомедицинских систем и биотехнологий

alexandr.erofeew@gmail.comVinokurovE. K.ВинокуровЕ. К.
Russian Federation

Institute of Biomedical Systems and Biotechnology

Институт биомедицинских систем и биотехнологий

alexandr.erofeew@gmail.comAntifeevI. E.АнтифеевИ. Е.
Russian Federation
alexandr.erofeew@gmail.comVlasovaО. L.ВласоваО. Л.
Russian Federation

Institute of Biomedical Systems and Biotechnology

Институт биомедицинских систем и биотехнологий

alexandr.erofeew@gmail.comBezprozvannyI. В.БезпрозванныйИ. Б.
Russian Federation

Institute of Biomedical Systems and Biotechnology, Department of Physiology

Институт биомедицинских систем и биотехнологий, Отделение физиологии

alexandr.erofeew@gmail.comPeter the Great St. Petersburg polytechnic universityСанкт-Петербургский Политехнический университет Петра ВеликогоInstitute of Analytical InstrumentationИнститут аналитического приборостроенияUniversity of Texas Southwestern Medical Center at DallasЮго-Западный медицинский центр Техасского университета1507202411071180120601022025Copyright ©; 2024, Russian Academy of SciencesCopyright ©; 2024, Российская академия наук2024Russian Academy of SciencesРоссийская академия наукhttps://transsyst.ru/0869-8139/article/view/651620

The miniature single-photon fluorescent microscope (miniscope) enables the visualization of calcium activity in vivo in freely moving laboratory animals, providing the capability to track cellular activity during the investigation of memory formation, learning, sleep, and social interactions. However, the use of calcium sensors for in vivo imaging is limited by their relatively slow (millisecond-scale) kinetics, which complicates the recording of high-frequency spike activity. The integration of methods from single-photon miniature fluorescent microscopy with electrophysiological recording, which possesses microsecond resolution, represents a potential solution to this issue. Such a combination of techniques allows for the simultaneous recording of optical and electrophysiological activity in a single animal in vivo. In this study, a flexible polyimide microelectrode was developed and integrated with the gradient lens of the miniscope. The in vivo tests conducted in this research confirmed that the microelectrode combined with the gradient lens facilitates simultaneous single-photon calcium imaging and local field potential recording in the hippocampus of an adult mouse.

Однофотонный миниатюрный флуоресцентный микроскоп (минископ) позволяет визуализировать кальциевую активность in vivo у свободно передвигающихся лабораторных животных, обеспечивая возможность отслеживания клеточной активности в ходе изучения процессов формирования памяти, обучения, сна и социального взаимодействия. Однако использование кальциевых сенсоров для прижизненной визуализации имеет ограничения, связанные с их относительно медленной (миллисекундной) кинетикой, что осложняет регистрацию высокочастотной спайковой активности. Интеграция методов однофотонной миниатюрной флуоресцентной микроскопии с электрофизиологической регистрацией, обладающей микросекундным разрешением, представляет собой потенциальное решение этой проблемы. Такое сочетание методов дает возможность одновременной регистрации оптической и электрофизиологической активности на одном животном in vivo. В данном исследовании разработан гибкий полиимидный микроэлектрод, который был совмещен с градиентной линзой минископа. Проведенные в исследовании тесты in vivo подтвердили, что совмещенный с градиентной линзой микроэлектрод реализует одновременную однофотонную кальциевую визуализацию и регистрацию локальных полевых потенциалов в гиппокампе взрослой мыши.

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