The effects of estradiol and epidermal growth factor on the material properties of the skeletally immature rabbit anterior cruciate ligament

Show full item record

Title: The effects of estradiol and epidermal growth factor on the material properties of the skeletally immature rabbit anterior cruciate ligament
Author: Cowden, Courtney
Abstract: There exists a troubling discrepancy between the number of anterior cruciate ligament (ACL ) injuries between males and females . Indeed , the root causes of this difference are multifactorial in nature . One possible factor is the presence of female sex hormones in the ACL and their effects on collagen production . Also , cross -talk is known to exist between the estrogen receptor and epidermal growth factor (EGF ) in reproductive tissues affecting collagen production . Twenty -four pre -pubescent New Zealand White rabbits were separated into three groups consisting of a control group receiving no hormones , a group receiving only estradiol , and a group receiving both estradiol and EGF . The rabbits were euthanized after the two -week period and had their hind limbs removed and frozen with soft tissue intact . All rabbit handling , hormone injections , and cataloging was performed by a separate laboratory creating a blind study environment . Before undergoing a standard tensile test , each ACL was analyzed using a 3D scanning technique capable of finding the minimal cross -sectional area and volume of the ligament . The test data was analyzed to assess significant differences in such values as the failure strength , strain at failure , modulus of elasticity , toughness , minimal cross -sectional area , length , and volume . Since all of the rabbits were pre -pubescent , no previous exposure to estradiol influenced the test results beyond the influence of the sex hormones which were administered . No differences were found between any groups for strain , length , minimal area , and volume . Estradiol was shown to lower the maximum stress by 39 % while EGF in addition to estradiol had no effect on that property . EGF in combination with estradiol significantly lowered the modulus of elasticity while significance could not be proven for the effect of estradiol alone on the modulus . Toughness behaved similarly to maximum stress in its response to estradiol and EGF . Estradiol induced collagen degradation is a viable explanation for these differences in maximum stress and toughness . Further testing is necessary to establish a relationship between estradiol , EGF , and the modulus of elasticity .
URI: http : / /hdl .handle .net /2346 /18331
Date: 2003-12

Citation

The effects of estradiol and epidermal growth factor on the material properties of the skeletally immature rabbit anterior cruciate ligament. Master's thesis, Texas Tech University. Available electronically from http : / /hdl .handle .net /2346 /18331 .

Files in this item

Files Size Format View
31295018735497.pdf 14.67Mb application/pdf View/Open

This item appears in the following Collection(s)

Show full item record

Search DSpace

Advanced Search

Browse