A TIME-DEPENDENT STUDY OF PASSIVE ESOPHAGEAL WALL PROPERTIES AND COLLAGEN CONTENT IN RABBITS WITH ESOPHAGEAL-VARICES

The passive biomechanical wall properties of the esophagus were studied in rabbits with esophageal varices and controls using a four-electrode impedance technique. Stepwise pressure inflation and deflation was done for analysis of esophageal cross-sectional area, compliance, and hysteresis monthly during six months. At sacrifice the esophageal collagen content was determined. A small but statistically insignificant increase in compliance was observed during the six-month observation period in both groups. No differences were observed between the groups (P > 0.3). No change in hysteresis was observed in either group. The group with esophageal varices had significantly higher collagen content in the distal esophagus when compared to controls (P < 0.05). No difference was demonstrated in the proximal part. No correlation was demonstrated between the collagen content and esophageal compliance. The study demonstrated that the method allows measurement of luminal cross-sectional area and tissue elasticity. No relationship was found, however, between the collagen content and compliance of the rabbit esophagus.