Monosodyum Glutamatın Normal Sıçan Yaşlanmasında Korteks ve Hipokampüs Üzerine Etkilerinin Araştırılması

Abstract

Amaç: Bu araştırma, Monosodyum Glutamat (MSG) uygulanan yaşlı sıçanların korteks ve hipokampüs dokularında dopamin taşıyıcısı (DAT), dopamin reseptörü 1 (D1) ve D2 ekspresyonlarını araştırmak amacıyla yapılmıştır. Yöntem: Deney gruplarının beyin dokularında hipokampüs ve korteksteki nöronal dejenerasyon ve genişlemiş kan damarları histopatolojik analizle değerlendirildi. DAT, D1 ve D2'nin immünoreaktivitesi immünohistokimyasal analizle belirlendi. Bulgular: Korteksteki nöronal dejenerasyon yaşlı sıçanlarda kontrol grubuna kıyasla anlamlı derecede daha yüksekti. Yaşlı sıçanların hipokampüsünde ve korteksinde DAT, D1 ve D2 reaktiviteleri kontrol grubuna kıyasla anlamlı derecede artmıştı. Sonuç: Yaşlı sıçanlar ve kontrol grubu arasında hipokampüs ve korteksteki genişlemiş kan damarları açısından anlamlı bir fark bulunmadı. Çalışmamızda yaşlı sıçanların hipokampüs ve korteks dokularında DAT, D1 ve D2 ekspresyonlarının artması dopaminin önemini vurgulayabilir. Verilerimiz yaşa bağlı motor ve bilişsel işlevlerdeki bozulmaların anlaşılmasında dopaminerjik yolaklara katkı sağlayabilir.

Keywords

• Yaşlanan Beyin
• D1
• D2
• Dopamin Taşıyıcısı
• İmmünohistokimya

Investigation of the Effects of Monosodium Glutamate on Cortex and Hippocampus in Normal Aging Rats

Abstract

Objective: This study aims to investigate the expressions of the dopamine transporter (DAT), dopamine receptor 1 (D1), and dopamine receptor 2 (D2) in the cortex and hippocampus tissues of monosodium glutamate (MSG)-administered aged rats. Method: Neuronal degeneration and dilated blood vessels in the hippocampus and cortex of the experimental groups’ brain tissues were evaluated by histopathological analysis. Immunoreactivity of DAT, D1, and D2 was determined by immunohistochemical analysis. Results: Neuronal degeneration in the cortex was significantly higher in aged rats than in the control group. DAT, D1, and D2 reactivities in the hippocampus and cortex of aged rats were significantly increased compared to those in the control group. Conclusion: No significant difference was found between the aged rats and the control group in terms of dilated blood vessels in the hippocampus and cortex. The increased DAT, D1, and D2 expressions in the hippocampus and cortex tissues of aged rats in our study may highlight the importance of dopamine. Our data may contribute to understanding age-related impairments in motor and cognitive functions through dopaminergic pathways.

Keywords

• Aging Brain
• D1
• D2
• Dopamine Transporter
• Immunohistochemistry

Supporting Institution

The author(s) received no financial support for the research, authorship, and/or publication of this article.

Ethical Statement

The present study was reviewed and approved by the institutional ethics committee of the Hatay Mustafa Kemal University Animal Experiments Local Ethics Committee in March 2022 (IRB Approval Number: 143582).

Thanks

The authors are grateful to all participants for their valuable contributions to this study.

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