title: Hyaluronan preserves peritoneal membrane transport properties.
abstract: BACKGROUND
  We have shown that intraperitoneal (i.p.) addition of hyaluronan (HA) in a single dwell study in rat could increase peritoneal fluid removal by decreasing the peritoneal fluid absorption rate. In this study, we investigated the impact of repeated use of HA on peritoneal membrane transport characteristics.
  
  
  METHODS
  Twelve male Sprague-Dawley rats received a once-daily i.p. injection of 25 mL 4.25% glucose dialysis solution without (HP group, n = 6) or with 0.025% HA (HA group, n = 6) for 1 week. Forty-eight hours after the last injection, a 4-hour dwell using 25 mL 4.25% glucose dialysis solution with i.p. volume marker and frequent dialysate and blood samplings was performed in each rat as well as in rats that did not receive any injection (control group, n = 8).
  
  
  RESULTS
  Although the i.p. volumes were significantly lower in the HP and HA groups compared to the control group, i.p. volume in the HA group was significantly higher than in the HP group. Net ultrafiltration at 4 hours was 5.6 +/- 1.3 mL, 10.2 +/- 1.8 mL, and 13.2 +/- 0.6 mL for the HP, HA, and control group, respectively. The peritoneal fluid absorption rate decreased by 45% in the HA group compared to the HP group. There was no significant difference in peritoneal fluid absorption rate between the HA and the control group. No difference was found in the direct lymphatic absorption rate between the HP and HA groups [0.010 +/- 0.003 mL/minute in the HP group and 0.011 +/- 0.004 mL/min in the HA group] although they were both higher than that of the control group (0.004 +/- 0.001 mL/min). The solute transport rates were in general significantly higher in the HP group compared to the HA and control groups, and there was no significant difference between the latter two groups, except that protein transport rate was significantly lower in the HA group compared to the control group.
  
  
  CONCLUSIONS
  The present study suggests that (1) repeated exposure to hypertonic glucose-based dialysis solution results in increased peritoneal solute transport rates, as well as increased peritoneal fluid absorption rates; and (2) these changes, reflecting a highly permeable peritoneal membrane, were ameliorated by repeated i.p. addition of hyaluronan. The similar changes in the direct lymphatic absorption rate in rats that received daily i.p. injection of dialysis solution suggest that direct peritoneal lymphatic absorption was not influenced by hyaluronan.
authors.affiliation: Department of Nephrology, First Affiliated Hospital, Sun Yat-sen University of Medical Sciences, Guangzhou, People's Republic of China.
authors.forename: Q Y
authors.initials: QY
authors.lastname: Guo
authors.forename: W X
authors.initials: WX
authors.lastname: Peng
authors.forename: H H
authors.initials: HH
authors.lastname: Cheng
authors.forename: R G
authors.initials: RG
authors.lastname: Ye
authors.forename: B
authors.initials: B
authors.lastname: Lindholm
authors.forename: T
authors.initials: T
authors.lastname: Wang
mesh_terms: D000042:Absorption; D000818:Animals; D001202:Ascitic Fluid / Q000378:metabolism; D001692:Biological Transport; D015314:Dialysis Solutions / Q000008:administration & dosage*; D005947:Glucose / Q000378:metabolism; D006820:Hyaluronic Acid / Q000008:administration & dosage / Q000494:pharmacology*; D007274:Injections, Intraperitoneal; D008196:Lymph / Q000378:metabolism; D008297:Male; D009994:Osmolar Concentration; D010530:Peritoneal Dialysis; D010537:Peritoneum / Q000187:drug effects / Q000378:metabolism*; D011506:Proteins / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D012711:Serum Albumin, Radio-Iodinated / Q000493:pharmacokinetics
chemical_list: D015314:Dialysis Solutions; D011506:Proteins; D012711:Serum Albumin, Radio-Iodinated; D006820:Hyaluronic Acid; D005947:Glucose