Comparison of Histomorphometric Characteristics of Heart and Aorta in Young Adult and Aged Rats

Abstract

Aim: The aim of this study was to compare the histomorphometric and immunohistochemical properties of the heart and aorta in young adult and aged rats. Material and Methods: Sixteen female Wistar albino rats, eight young adult (6 months old, female, 233.25±13.85 g) and rats were used in the study. The rats were sacrificed under high dose anaesthesia and heart and aortic tissues were collected. Ventricular and septum interventiculare thicknesses were measured on the heart tissues, tunica media, tunica intima thickness and aortic diameter were measured histomorphometrically on the aortic tissues. In addition, Inducible Nitric Oxide Synthase (iNOS) in the smooth muscle cells of the tunica media of the aorta and occludin protein levels in the aorta and heart endothelium were examined by immunohistochemical method and histological scoring was performed. Results: As a result of statistical analysis, body weight, heart weight, heart weight/body weight ratio, tunica media and intima thicknesses, and aortic diameters were found to be statistically significantly higher in aged rats compared to young adult rats (p<0.05). Among the cardiac measurements, only the left ventricle/heart weight ratio was found to be statistically significantly higher in young adults than in aged rats (p<0.05). In addition, according to the H scoring of the data obtained as a result of immunohistochemical staining for iNOS protein, iNOS protein level was found to be higher in aged rats than in young rats (p<0.05). Immunohistochemical staining for occludin in aorta and heart endothelial cells of aged rats revealed weaker staining compared to young rats. Conclusion: In general, our study emphasises the importance of understanding the histomorphometric changes that occur in heart and aortic tissue as a result of aging. Further research is needed to better understand the mechanisms underlying these age-related changes and to identify potential therapeutic targets for the prevention and treatment of cardiovascular diseases in elderly individuals

Keywords

• Ageing
• aorta
• heart
• histomorphometry
• iNOS

Supporting Institution

None to declare.

Ethical Statement

Ethics committee approval numbered 2023-16-07/09 was obtained from Zonguldak Bülent Ecevit University Animal Experiments Local Ethics Committee for the study.

Thanks

None

Genç Erişkin ve Yaşlı Sıçanlarda Kalp ve Aort’un Histomorfometrik Özelliklerinin Karşılaştırılması

Abstract

Amaç: Bu çalışmanın amacı, genç erişkin ve yaşlı sıçanlarda kalp ve aortun histomorfometrik ve immünohistokimyasal özelliklerini karşılaştırmaktır. Gereç ve Yöntemler: Çalışmada sekiz genç erişkin (6 aylık, dişi, 233,25±13,85 g) ve sekiz yaşlı (24 aylık, dişi, 257,12±17,48 g) olmak üzere toplam on altı dişi Wistar albino sıçan kullanıldı. Deneye dahil edilen sıçanlar yüksek doz anestezi altında sakrifiye edilerek kalp ile aort dokuları toplandı. Kalp dokuları üzerinden ventrikül ve septum interventiculare kalınlıkları ölçülürken aort dokusu üzerinde tunica media ve tunica intima kalınlığı, aort çapı histomorfometrik olarak ölçüldü. Ayrıca aortaların tunica medialarının düz kas hücrelerinde Inducible Nitric Oxide Synthase (iNOS) ve aorta ve kalp endotelinde okludin protein düzeyleri immünohistokimyasal yöntemle incelendi ve histolojik skorlama yapıldı. Bulgular: Yapılan istatistiksel analiz sonucunda yaşlı sıçanlarda vücut ağırlığı, kalp ağırlığı, kalp ağırlığı/ vücut ağırlığı oranı, tunica media ve intima kalınlıkları, aort çapları genç erişkin sıçanlara göre istatistiksel olarak anlamlı seviyede yüksek olduğu tespit edildi (p<0.05). Kalp ölçümlerinden sadece sol ventrikül/ kalp ağırlığı oranının genç erişkinlerde yaşlı sıçanlara göre istatistiksel olarak anlamlı seviyede yüksek olduğu belirlendi (p<0.05). Ayrıca iNOS proteini için yapılan immünohistokimyasal boyama sonucunda elde edilen verilerin H skorlamasına göre yaşlı sıçanlarda iNOS protein düzeyi gençlere göre yüksek bulundu (p<0.05). Yaşlı sıçanların aorta ve kalp endotel hücrelerinde okludin için yapılan immünohistokimyasal boyama sonucunda genç sıçanlara göre daha zayıf boyanma gözlendi. Sonuç: Genel olarak çalışmamız, yaşlanmanın bir sonucu olarak kalp ve aort dokusunda meydana gelen histomorfometrik değişikliklerin anlaşılmasının önemini vurgulamaktadır. Yaşa bağlı bu değişikliklerin altında yatan mekanizmaları daha iyi anlamak ve yaşlı bireylerde kardiyovasküler hastalıkların önlenmesi ve tedavisine yönelik potansiyel terapötik hedefleri belirlemek için daha fazla araştırmaya ihtiyaç vardır.

Keywords

• Aort
• histomorfometri
• iNOS
• kalp
• yaşlanma

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