title: Effect of concentration and hyaluronidase on restriction of hetastarch flux through lung interstitial segments.
abstract: The transport properties of lung interstitium were studied by measuring the flow of hetastarch solution (2 and 6%) through 1-cm perivascular interstitial segments of rabbit lungs. Hetastarch (10(4)-10(7) Da) solution has a colloid osmotic pressure similar to that of albumin solution. Driving pressure was 5 cm H(2)O and mean interstitial pressure was 0 cm H(2)O. The flows of 2 and 6% hetastarch solutions were measured before (Q(1)) and after (Q(2)) the addition of 0.02% hyaluronidase. Hetastarch molecular distributions in effluent samples were measured by high-performance size-exclusion chromatography (HPSEC) to determine sieving ratio (C(out)/C(in), downstream-to-upstream concentration ratio). Hyaluronidase significantly (P < 0.0004) increased flow sixfold, but the increase in flow (Q(2)/Q(1)) was reduced through the interstitium around smaller vessels. A similar behavior was observed with the flow of albumin solution without and with hyaluronidase. C(out)/C(in) decreased monotonically with molecular weight, was greater with 6% than with 2% (low colloid osmotic pressure) hetastarch, and increased with hyaluronidase. Modeling the transport through uniform pores, equivalent pore radius was 10 and 15 nm with 2 and 6% hetastarch, respectively, and doubled with hyaluronidase. In conclusion, interstitial pores expand in response to an increase in colloid osmotic pressure both before and after tissue degradation by hyaluronidase.
authors: Center for Biomedical Engineering, University of Kentucky, Lexington, KY 40506-0070, USA.
authors: N E
authors: NE
authors: Aronson
authors: P K
authors: PK
authors: Houtz
authors: S
authors: S
authors: Villarruel
authors: R L
authors: RL
authors: Conhaim
authors: K E
authors: KE
authors: Watson
authors: S J
authors: SJ
authors: Lai-Fook
mesh_terms: D000818:Animals; D002851:Chromatography, High Pressure Liquid; D006821:Hyaluronoglucosaminidase / Q000378:metabolism / Q000494:pharmacology*; D006895:Hydroxyethyl Starch Derivatives / Q000494:pharmacology*; D008168:Lung / Q000187:drug effects / Q000473:pathology*; D008833:Microcirculation; D008962:Models, Theoretical; D009997:Osmotic Pressure; D010952:Plasma Substitutes / Q000494:pharmacology; D011312:Pressure; D011817:Rabbits; D013997:Time Factors; D014867:Water / Q000737:chemistry
chemical_list: D006895:Hydroxyethyl Starch Derivatives; D010952:Plasma Substitutes; D014867:Water; D006821:Hyaluronoglucosaminidase