Histological evaluatıon of structures similar to the cartilago cordis in the rat heart: A case report

Rasim Hamutoğlu; Serpil Ünver Saraydin

doi:10.19161/etd.1841533

TR EN

Rat kalbinde cartilago cordis benzeri yapıların histolojik olarak değerlendirilmesi: Bir olgu sunumu

Abstract

Ossa cordis sığırlarda gözlenen ve kardiyak iskeletin bir bileşeni olarak tanımlanan bir yapı olup, diğer memeli hayvanlarda cartilago cordis olarak adlandırılmaktadır; ancak cartilago cordis’in küçük memelilerde, özellikle kemirgenlerde varlığına ilişkin bilgiler sınırlıdır. Bu çalışma, Wistar albino sıçanının kalbinde rastlantısal olarak gözlenen kıkırdak benzeri yapıları rapor etmekte ve bunların morfolojik ve histolojik özelliklerini incelemektedir. Hematoksilen–eozin ile yapılan boyamada, kollajen açısından zengin, kompakt ve kıkırdak benzeri matriks içeren bölgeler tespit edilmiş olup, bu yapılar atriyoventriküler halka ve kapak bağlantı bölgelerinde, yani mekanik strese maruz kalan alanlarda lokalize olmuştur. Kıkırdak normal bir kalp bileşeni olmamasına rağmen, mezanşimal hücrelerin kondroblasta farklılaşması, kıkırdak matriks üretimi ve endokondral ossifikasyon gibi aktif, hücre aracılı kalsifikasyon süreçlerinin kardiyovasküler sistemde gerçekleştiği bilinmektedir. Kalsifiye kapaklarda gözlenen kondrosit benzeri hücreler, tip II ve X kolajen ile osteojenik proteinlerin varlığı, kardiyak dokuda osteojenik fenotipi desteklemekte ve benzer bir sürecin sıçan kalbinde de olabileceğini düşündürmektedir. Bu bulgular, cartilago cordis’in mekanik destek sağlama, yük dağılımı ve iletim–kasılma dinamiklerini modüle etme gibi adaptif bir yapı olarak işlev görebileceğini göstermektedir.

Keywords

Histological evaluatıon of structures similar to the cartilago cordis in the rat heart: A case report

Abstract

Ossa cordis is a structure identified in cattle as a component of the cardiac skeleton, whereas in other mammalian species this structure is referred to as cartilago cordis; however, information regarding the presence of cartilago cordis in small mammals, particularly rodents, remains limited. This study reports incidentially observed cartilage-like structures in heart of a Wistar albino and examines their morphological and histological features. Hematoxylin–eosin staining revealed collagen-rich compact areas with cartilage-like matrix, localized near the atrioventricular ring and valve attechment sites, regions exposed to mechanical stress. Although cartilage is not a normal cardiac component, active, cell-mediated calcification processes including differentiation of mesenchymal cells into chondroblasts, cartilage matrix production, and endochondral ossification are recognized in the cardiovascular system. The presence of chondrocyte-like cells, type II and X collagen, and osteogenic proteins in calcified valves supports an osteogenic phenotype in cardiac tissue, suggesting a similar process may occur in rats. These findings imply that cartilago cordis may function as an adaptive structure, contributing to mechanical support, load redistribution, or modulation of conduction–contraction dynamics. In conclusion, this study identifies hyaline cartilage-like formations resembling cartilago cordis in the rat heart, providing a novel perspective on interspecies anatomical variation and cardiac mineralization, and highlighting the potential universality and biological significance of heterotopic cartilage and bone formation in the heart.

Keywords

Ethical Statement

This case report presents an incidental finding detected in an adult, 4-year-old, female Wistar albino rat weighing 210–230 g. The rat was originally used in a seperate research Project focused on comparing paraffin and JB-4 embedding techniques in light microscopy. In that study, the heart tissue was not part of the intended analysis; however, during routine tissue processing, a cartilaginous structure was incidentially observed in the heart, which was unrelated to the original experimental aim. Throughout the experimental period, the rat was maintained under standard laboratory conditions with a 12-hour light/12-hour dark cycle and provided ad libitum access to water and pellet chow. Ethical approval for the original study was granted by the local Animal Experiments Ethics Committee (Approval No: 65202830-050.04.04.-13, dated 05.03.2025).

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Details

Primary Language

English

Subjects

Pathology

Journal Section

Case Report

Authors

Rasim Hamutoğlu ^*
0000-0002-2474-5336
Türkiye

Serpil Ünver Saraydin
0000-0001-7639-7487
Türkiye

Publication Date

June 10, 2026

Submission Date

December 13, 2025

Acceptance Date

December 30, 2025

Published in Issue

Year 2026 Volume: 65 Number: 2

DOI

https://doi.org/10.19161/etd.1841533

IZ

https://izlik.org/JA66CC25GB

Cite

RIS / Bibtex

APA

Hamutoğlu, R., & Ünver Saraydin, S. (2026). Histological evaluatıon of structures similar to the cartilago cordis in the rat heart: A case report. Ege Tıp Dergisi, 65(2), 336-339. https://doi.org/10.19161/etd.1841533

AMA

1.Hamutoğlu R, Ünver Saraydin S. Histological evaluatıon of structures similar to the cartilago cordis in the rat heart: A case report. EJM. 2026;65(2):336-339. doi:10.19161/etd.1841533

Chicago

Hamutoğlu, Rasim, and Serpil Ünver Saraydin. 2026. “Histological Evaluatıon of Structures Similar to the Cartilago Cordis in the Rat Heart: A Case Report”. Ege Tıp Dergisi 65 (2): 336-39. https://doi.org/10.19161/etd.1841533.

EndNote

Hamutoğlu R, Ünver Saraydin S (June 1, 2026) Histological evaluatıon of structures similar to the cartilago cordis in the rat heart: A case report. Ege Tıp Dergisi 65 2 336–339.

IEEE

[1]R. Hamutoğlu and S. Ünver Saraydin, “Histological evaluatıon of structures similar to the cartilago cordis in the rat heart: A case report”, EJM, vol. 65, no. 2, pp. 336–339, June 2026, doi: 10.19161/etd.1841533.

ISNAD

Hamutoğlu, Rasim - Ünver Saraydin, Serpil. “Histological Evaluatıon of Structures Similar to the Cartilago Cordis in the Rat Heart: A Case Report”. Ege Tıp Dergisi 65/2 (June 1, 2026): 336-339. https://doi.org/10.19161/etd.1841533.

JAMA

1.Hamutoğlu R, Ünver Saraydin S. Histological evaluatıon of structures similar to the cartilago cordis in the rat heart: A case report. EJM. 2026;65:336–339.

MLA

Hamutoğlu, Rasim, and Serpil Ünver Saraydin. “Histological Evaluatıon of Structures Similar to the Cartilago Cordis in the Rat Heart: A Case Report”. Ege Tıp Dergisi, vol. 65, no. 2, June 2026, pp. 336-9, doi:10.19161/etd.1841533.

Vancouver

1.Rasim Hamutoğlu, Serpil Ünver Saraydin. Histological evaluatıon of structures similar to the cartilago cordis in the rat heart: A case report. EJM. 2026 Jun. 1;65(2):336-9. doi:10.19161/etd.1841533