CONTRIBUTION OF CHONDROITIN-DERMATAN SULFATE-CONTAINING PROTEOGLYCANSTO THE FUNCTION OF RAT MESENTERIC-ARTERIES

Proteoglycans are an important nonfibrous matrix component of the arte rial wall. Direct evidence for their role in resistance-sized arteries is lacking, although they likely have an important role in coordinati ng and regulating vessel behavior, presumably via interactions of thei r glycosaminoglycan chains or core proteins with other matrix molecule s and/or the smooth muscle cell surface. The purpose of this study was to determine whether the removal of specific glycosaminoglycan chains from proteoglycans in resistance-sized mesenteric arteries would chan ge the mechanical properties of the arterial wall, thereby affecting t heir functional behavior. The major finding of the study was that 65% removal of chondroitin-dermatan sulfate-containing glycosaminoglycans from the arterial wall increased vascular wall stiffness and altered t he myogenic behavior of the artery. The significant alterations in myo genic behavior associated with changes in passive mechanics following partial glycosaminoglycan chain removal support our hypothesis that ch ondroitin-dermatan sulfate-containing proteoglycans contribute signifi cantly to the functional behavior of resistance arteries. We speculate that these alterations are the result of changes in stress transfer b etween collagen fibrils and/or stress transfer between cells and colla gen fibrils under applied pressure.