Enterocytes were isolated from the jejunum and ileum of the neonatal (12-day-old) rat by vibrating everted intestinal segments in buffered saline containing EDTA. The isolated cells appeared morphologically normal when examined microscopically, retaining their in vivo shape and internal structure. Enzyme analysis revealed that over 80% of the total gut lactase activity was associated with the isolated enterocytes. During incubation at 37 °C the cells maintained their structure for 30–60 min and consumed oxygen and produced lactate at a constant rate for at least 45 min. On the basis of these tests it was concluded that the method yielded large numbers of enterocytes which were able to be maintained in simple media without significant loss of structure or function for at least 45 min at 37 °C. Comparison of the metabolic activities of cells isolated from the two regions suggests that ileal enterocytes maintain the greater functional integrity, maintaining an intact plasma membrane for longer periods and having higher respiratory and glycolytic activities.

The effect of inhibitors of respiration (NaN3 and DNP), glycolysis (2DG, IAA and NaF) and the microtubular-microfilament system (colchicine and cytochalasin B) on the uptake of rat immunoglobulin G (IgG) by enterocytes isolated from the neonatal rat gut has been assessed. After a 1 hour incubation, NaN3, and DNP had significantly reduced IgG uptake by between 32% and 35% of the control, IAA and 2DG were less effective and NaF, colchicine and cytochalasin B had no effect at all. The findings show that IgG is internalised by isolated enterocytes in vitro and that this internalisation is under metabolic control, that inhibitors of respiration are more effective in blocking uptake than inhibitors of glycolysis.