title: Increased negativity of interstitial fluid pressure contributes to development of oedema in rat skin following application of xylene.
abstract: Intradermal interstitial fluid pressure (Pi) has been studied in rat skin during formation of inflammatory oedema caused by application of xylene. Pi was measured with sharpened micropipettes connected to a servocontrolled counter-pressure system. Control Pi averaged -1.3 +/- 0.6 (SD) mmHg. Following xylene application Pi decreased to -5.0 mmHg after 5 min and then increased to stabilize at about 0 mmHg at 45-60 min and later. When the transvascular fluid shifts accompanying the inflammatory reaction were prevented by inducing circulatory arrest prior to xylene application, Pi fell to -7.5 mmHg within 5 min and remained at this level throughout the observation period of 90 min. Aprotinin in large doses (80,000 KIE kg-1) before xylene application reduced the fall in Pi, whereas indomethacin had no effect. The increased negativity in Pi will add directly to a normal transcapillary net filtration pressure of about 0.5 mmHg, resulting in a 10- to 20-fold increase in this pressure. The present experiments therefore suggest that the interstitium plays an active role in oedema formation in the initial phase of xylene-induced inflammation in rat skin through the development of an increased negativity of Pi.
authors.affiliation: Department of Physiology, University of Bergen, Norway.
authors.forename: S A
authors.initials: SA
authors.lastname: Rodt
authors.forename: H
authors.initials: H
authors.lastname: Wiig
authors.forename: R K
authors.initials: RK
authors.lastname: Reed
mesh_terms: D000818:Animals; D007611:Aprotinin / Q000494:pharmacology; D004487:Edema / Q000209:etiology* / Q000517:prevention & control; D005110:Extracellular Space / Q000187:drug effects / Q000502:physiology; D007213:Indomethacin / Q000494:pharmacology; D011312:Pressure; D051381:Rats; D011919:Rats, Inbred Strains; D012867:Skin / Q000187:drug effects*; D012879:Skin Physiological Phenomena; D014992:Xylenes / Q000633:toxicity*
chemical_list: D014992:Xylenes; D007611:Aprotinin; D007213:Indomethacin