MECHANICAL-PROPERTIES OF SMALL FEMORAL ARTERIES IN SPONTANEOUSLY HYPERTENSIVE RATS

The purpose of the study was to compare the mechanical properties of s mall femoral arteries from spontaneously hypertensive rats (SHR) normo tensive control Wistar-Kyoto rats (WKY) determine whether these could contribute to the narrowed lumens and thicker medial layers observed d uring the development of hypertension. Rats were used at either 5,12, or 24 weeks of age. Third order branches of the right femoral artery w ere mounted in a myograph for morphological measurement and determinat ion of wall mechanical properties. At 5 weeks SHR and WKY arteries wer e structurally similar but progressive medial thickening and hypertrop hy in conjunction with lumenal narrowing was observed in SHR compared with those from WKY in the older rats. However, stress-strain and incr emental elastic modulus-stress relationships were similar between stra ins at all three ages. These data indicate that modifications of arter ial wall mechanical properties do not contribute to these progressive arterial structural modifications.