[Is there a feed-back mechanism between serum gastrin concentration and gastrin release (author's transl)]

The dialysability of gastrin heptadecapeptide was investigated in a model arrangement. The amounts of gastrin passing through the dialysis membrane during a 6-hour dialysis procedure are very small. Furthermore, the serum gastrin concentrations were measured during a 6-hour haemodialysis session with and without simultaneous pentagastrin infusion (0.003 mug/kg/h) in 8 patients on intermittent haemodialysis. There is a continuous decrease in the serum gastrin concentration during the 6-hour dialysis period with simultaneous pentagastrin infusion, while in the investigation without pentagastrin infusion phases of increase in serum gastrin levels are observed. In view of this different response of the serum gastrin curve it is suggested that a direct feed-back mechanism exists between the serum gastrin concentration and gastrin release, a mechanism which was interrupted by the pentagastrin infusion in the present investigation.