ABSTRACT
This chapter focuses on how the regulation is achieved by lymph drainage and by automatic edema-preventing mechanisms of the interstititum. The major structural component of the interstitium is collagen, which forms a framework for the interstitium. Collagen is built up from slightly coiled rodlike molecules constituting a triple helix. Hyaluronan exhibits entanglement and a high viscosity even at low concentrations and also exhibits exclusion properties toward plasma and collagen. Proteoglycans are metabolized by the same liver endothelial cells as the hyaluronan, but it is not known how important this catabolism is compared to that taking place in tissue or in lymph nodes. J. R. Levick has reviewed available literature on interstitial hydraulic conductivity and its dependence on the different interstitial components. In the complete absence of lymph drainage the interstitial protein concentration will therefore rise toward plasma level. This increases net filtration pressure and causes expansion of the interstitium.
