Postoperative weight increase after total gastrectomy by CCK-antagonists

273 E F F E C T O F B O M B E S I N ON [CA*~]i AND P R O L I F E R A T I O N O F LYMPHOCYTES ISOLATED FROM LAMINA PROPRIA, PEYER'S PATCHES, AND SPLEEN. Waetke R, Liehr RM, Bordasch K, Hailer H, Zeitz M, Riecken EO, Gregor M. Department of Gastroenterology, Free University of Berlin, Berlin, Germany. V1P and substance P have been shown to modulate proliferation of Con A-stimulated intestinal lymphoeytes. Only few data are available of the effects of bombesin on various compartments of the immune system. We therefore examined the immunomodulatory effects of bombesin on lymphocytes from lamina propria (LPL), Peyer's patches (PPL), and spleen (SL) in mice. LPL, PPL and SL were separated by Percoll/Ficoll gradients, and were incubated with 0.5 ~tg/ml Con A and bombesin (10 -5 to 10 "13 M). After 48 h [3H]-thymidine was added for 24 h. In eddition, the effects of spleen accessory cells on lymphocytes were observed in the presence of bombesin. Intracellular calcium ([Ca++]i) signal was measured using fura-2AM as fluorescence marker. Furthermore the presence of specific bombesin receptors was examined by 125J-bombesin receptor binding assays. Proliferation of lymphocytes from all three compartments was significantly stimulated by Con A. In contrast to VIP (Gregor et al., Gastroenterology 1992) bombesin did not alter DNA synthesis of LPL, PPL, and SL. [3H] thymidine uptake of accessory cells and nonadherent lymphocytes, separated by adherence technique, remained unchanged in response to bombesin treatment. Con A stimulation resulted in a significant increase of [Ca++]i concentration. When bombesin was added, no increase of [Ca+*]i was observed. Binding studies with 125J-bombesin revelled the absence of specific bombesin receptors on LPL, PPL, and SL. C o n c l u s i o n s : In contrast to VIP, bombesin is not a direct modulator of mouse LPL, PPL, and SL function.

BIOLOGICAL AND IMMUNOLOGICALGASTRIN ACTIVITY IN SERUM OF PATIENTS WITH GASTRINOMA. BIOASSAYOF GASTRIN ACTIVITY IN SERUM Waldum HL, Mignon M,*, Sandvik AK, Bonfils S*. Department of Medicine, University Hospital of Trondheim, Norway and H6pital Bichat*, Paris, France The biological gastrin activity in serum from 17 patients with Zollinger-Ellison syndrome was assessed by the stimulation of histamine release and acid secretion from the isolated vasculady perfused rat stomach, and compared with the immunological activity as determined by radioimmunoassay using an antibody directed towards the active site of the gastrin molecule. Biological gastrin activity assessed by the stimulation of histamine release was more closely correlated to immunological gastrin activity than biological activity assessed by the stimulation of gastric acid secretion. This study thus strengthens the concept that gastrin stimulates acid secretion at least partly by releasing histamine, and also shows that the immunological gastrin activity determined by means of an antibody directed towards active site reflects biological activity.