EN
The importance of stirring on the peritoneal absorption and excretion of urea (U), uric acid (UA), inulin (I) and albumin (A) in vitro was analysed. Changes of mixing rate modified the dynamics of the peritonea1 transport. These modifications were transient. The increase of stirring intensity from 5 ml/min to 11 ml/min caused increase of the mean bidirectional transfer values of UA by about 40% and A by 70%, but not U and I. The increase of mixing from 11 ml/min to 22 ml/min elevated only transperitoneal transfer of A by about 110 % in comparison with the control. The obtained results confirm the suggestion that increasing of fluid mixing on the mesothelial and interstitial side of the membrane influences the transperitoneal transfer rate by reduction of unstirred fluid layer. This diffusion resistance in vitro, in contrast to in vivo, is more important for the transport of macromolecular than micromo1ecu1ar, neutral solutes.