J Korean Soc Plast Reconstr Surg.  1999 Jan;26(1):99-104.

The Effect of Estrogen on Transformation of Rabbit Ear

• Oh K
• Kim JH
• Kim JT
• Kim SK

Abstract

Congenital auricular deformities such as lop ear, cup ear, prominent ear, and Stahl's ear can be corrected nonsurgically in the early neonatal period(first week after birth) obtaining satisfactory results. Auricular cartilage consists of chondrocytes and intercellular materials that are mainly assembled from collagen, elastin, and a proteoglycan aggergate. Cartilageelasticity is dependent upon the concentration of the proteoglycan aggregate. Hyaluronic acid, which is a constituent of proteoglycan aggregate and is increased by estrogens, has an important play on disconnecting the proteoglycan aggregate. So the increased estrogen results in the lack of elasticity. The circulating levels of free estradiol are higher during the first 72 hours after birth and decreases thereafter, so the ear is soft and easily malleable in this early neonatal period. In this study, we have applied aluminium splint (90 degree-angulated, 180 degree-angulated, and rolled) on rabbit ear. All of the rabbit was divided into 3 groups containing 3 types of deformities. In group 1, estrogen was applied to the deformed ear with regional injection to the perichondrium of auricular cartilage. In group 2. estrogen was applied topically with ointment. In group 3, as control group, saline was injected to the perichondrium. Four weeks later, in group 2, the shape of the deformed rabbit ear was maintained, and did not return to its original shape even after splint removal. From these results, we concluded that estrogen ointment could be tried as adjunctive therapeutic modalities to the nonsurgical treatment of the congenital auricular deformities.

MeSH Terms

Chondrocytes
Collagen
Congenital Abnormalities
Ear Cartilage
Ear*
Elasticity
Elastin
Estradiol
Estrogens*
Hyaluronic Acid
Parturition
Proteoglycans
Splints
Collagen
Elastin
Estradiol
Estrogens
Hyaluronic Acid
Proteoglycans