[Effects of pentagastrin and heptagastrin on acid secretion in man (author's transl)]

Gastrin analogues are known to stimulate acid secretion with higher potency the more amino acids prolong the peptid chain towards the N-terminal end. In order to compare the response of pentagastrin (Gastrodiagnost, Merck, Darmstadt) and Heptagastrin (HOE 293, Hoechst AG, Frankfurt/M.) in 12 healthy subjects the two peptides were given subcutaneously in doses of 1 microgram/kg, 3 microgram/kg and 6 microgram/kg body weight. Additionally in 8 subjects 1 microgram/kg/h and 2 microgram/kg/h of the gastrins were given intravenously. Gastric content was aspirated under basal and stimulated conditions in portions of 15 minutes, volume (ml) and acid concentration (meq/l) of each fraction was measured and acid secretion (meq/90'), BAO and PAO were calculated. As compared with pentagastrin the dose response curve was shifted to the left, when heptagastrin was given subcutaneously. The amount of acid secretion over a time period of 90 min. was about 17% higher after heptagastrin than after pentagastrin. There was no difference between the peak acid outputs (PAO). Stimulation of acid secretion was prolonged after heptagastrin as compared to pentagastrin. Both gastrins acted similarly on all parameters measured when administered intravenously. Side effects as nausea and dizziness were observed in two subjects of each group.