Modifications of tissue blood flow in acute pancreatitis

1. Acute pancreatitis (AP) was induced by ductal injection of 2.5% sodium taurocholate saline solution. Plasma and red blood cell (RBC) volume and visceral organ blood flow were evaluated by a radioisotopic method (51Cr tracers) in 45 adult male Wistar rats (22 submitted to AP and 23 controls) 4 h after AP induction. 51Cr-albumin was used to measure plasma volume and 51Cr-RBC was used to measure RBC volume. 2. Changes in tissue hematocrit reflect alterations in tissue blood flow, since reduction in blood flow increases microvascular erythrocyte sequestration. To evaluate the tissue blood flow, we introduce a "tissue hematocrit index" calculated by relating 51Cr-RBC and 51Cr-albumin specific activities measured in visceral organ biopsies. Application of this index to the control and AP groups showed a decrease in blood flow in all visceral organs of the AP group which was reflected by an increase in tissue hematocrit index (2.5-fold for kidneys, 2-fold for pancreas and lungs, 1.6-fold for liver, and 1.2-fold for spleen). 3. As expected, there was an increase in blood hematocrit and a decrease in plasma volume in the AP group, but there were no significant alterations in RBC volume. However, an unequal decrease in blood flow in various tissues such as kidneys, lungs, pancreas and liver was detected in the AP group. 4. This approach provides an easy and simple way to evaluate possible therapeutic protocols for the treatment of acute pancreatitis by measuring effects on visceral blood flow and plasma and blood volumes.