Immunocytochemical localization of gastric inhibitory peptide (GIP) in the human foetal pancreas.

The occurrence of gastrin and gastric inhibitory polypeptide (GIP) was investigated immunocytochemically in 17 foetal and neonatal human pancreata of gestational ages ranging from 12-41 weeks. GIP immunoreactive cells were observed in the pancreas of five foetuses with gestational ages of 18-20 weeks. These cells were located in islet-like cell clusters, at the base of tubular structures and among the exocrine-like acini. They were sometimes seen to emit a single long protrusion. The controls used, including preincubation of the antisera with anticomplement Clq, emphasized the specificity of the observed immunoreaction. No gastrin-immunoreactive cells were seen in any of the foetal or neonatal pancreata examined.