Scientific article
Effects of estrogen on the condylar cartilage of the rat mandible in organ culture,☆☆

https://doi.org/10.1016/S0278-2391(99)90823-6Get rights and content

Abstract

Purpose: The effects of estrogen on bone have been well documented. However, very little is known about the regulatory role of estrogen on cartilage and, in particular, the secondary cartilage of the mandibular condyle. The aims of this study were to determine whether estrogen receptors are present in the condylar cartilage of the rat mandible and to assess the effect of varying 17β-estradiol (E2) concentrations on the proteoglycan content of this tissue.

Materials and Methods: Mandibular condyles of 16 female Sprague-Dawley rats were resected. Eighteen of these condyles were divided into three groups and the condylar cartilage was removed and placed in organ culture for 4 days with media containing different concentrations of estrogen: 10−11 mol/L, 10−8 mol/L, and 10−6 mol/L. The cartilage then was analyzed for proteoglycan content along with six specimens not passed through the organ culture. Six intact mandibular condyles also were resected and placed in organ culture with the same varying E2 concentrations, and the condylar cartilage was analyzed for estrogen receptors along with two condyles not passed through the culture system.

Results: Estrogen receptors were evenly distributed within the chondroblastic and hypertrophic zones in the control group and the group with 10−11 mol/L E2. With E2 concentrations of 10−8 mol/L and 10−6 mol/L, there was a qualitative decrease in hypertrophic chondroblasts, thickness of the condylar cartilage, and a significant decrease in proteoglycan content.

Conclusions: This study shows the presence of estrogen receptors in the secondary cartilage of the rat mandibular condyle. Estrogen has the potential to cause a decrease in extracellular matrix and thickness of this cartilage.

References (24)

Cited by (35)

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Received from Baylor College of Dentistry, a member of the Texas A&M University System, Dallas, TX.

☆☆

This study was supported by BCD-TAMUS intramural research and the Center for Craniofacial Research and Diagnosis Funds.

Instructor, Department of Biomedical Sciences.

Assistant Professor, Department of Oral and Maxillofacial Surgery/ Pharmacology, and Department of Biomedical Sciences.

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Associate Professor, Department of Biomedical Sciences.

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