Effect of the lectins wheat germ agglutinin (WGA) and Ulex europaeus agglutinin (UEA-I) on the alpha-amylase secretion of rat pancreas in vitro and in vivo.
Lectins are able to bind to cholecystokinin (CCK) receptors and other glycosylated membrane proteins. The lectins wheat germ agglutinin (WGA) and Ulex europaeus agglutinin (UEA-I) are used for affinity chromatography to isolate the highly glycosylated CCK-A receptor of pancreatic acinar cells. According to the working hypothesis that lectin binding to the CCK receptor should alter the ligand-receptor interaction, the effect of WGA and UEA-I on CCK-8-induced enzyme secretion was studied on isolated rat pancreatic acini in vitro. In vitro both lectins showed a dosage-dependent inhibition of CCK-8-induced alpha-amylase secretion of acini over 60 min. WGA showed a strong inhibitory effect on amylase secretion, approximately 40%, in vitro. UEA-I caused a smaller, but significant decrease, approximately 20%, in enzyme secretion of isolated acini. Additionally, both lectins inhibited cerulein/secretin- or cerulein-induced pancreatic secretion of rats in vivo, but not after secretin alone. The results are discussed with respect to a possible influence of both lectins on the interaction of CCK or cerulein with the CCK-A receptor.
Mikkat
U
U
Department of Pathology, University of Rostock, Germany.
Damm
I
I
Schröder
G
G
Schmidt
K
K
Wirth
C
C
Weber
H
H
Jonas
L
L
D000818:Animals; D066298:In Vitro Techniques; D037102:Lectins / Q000494:pharmacology*; D008297:Male; D010179:Pancreas / Q000201:enzymology*; D037121:Plant Lectins; D051381:Rats; D011917:Rats, Inbred Lew; D012844:Sincalide / Q000494:pharmacology; D014909:Wheat Germ Agglutinins / Q000494:pharmacology*; D000516:alpha-Amylases / Q000378:metabolism*
D037102:Lectins; D037121:Plant Lectins; C036850:Ulex europaeus lectins; D014909:Wheat Germ Agglutinins; D000516:alpha-Amylases; D012844:Sincalide