Gastrin has a specific proliferative effect on the rat enterochromaffin-like cell, but not on the parietal cell: A study by elutriation centrifugation

Gastrin has a general growth-promoting effect on gastric oxyntic mucosa, an d a more pronounced one on the enterochromaffin-like (ECL) cell. Whether ga strin has a proliferative effect on the parietal cell lineage beyond the ge neral effect is uncertain. Hypergastrinaemia was evoked in rats using panto prazole (group II: 100 mu mol kg(-1), group III: 400 mu mol kg(-1)) for 45 days. Plasma gastrin was 43 +/- 8 pmol L-1 (control), 283 +/- 54 pmol L-1 ( group II) and 577 +/- 63 pmol L-1 (group III). Gastric mucosal cells were i solated and fractionated by elutriation centrifugation. Total cell number, percentage and number of ECL and parietal cells, and histamine were determi ned in each fraction. The number of mucosal cells increased 1.5-fold in bot h hypergastrinaemic groups. Enterochromaffin-like cell content was 2.6 +/- 0.5% (control), 6.0 +/- 0.6% (group II) and 9.0 +/- 0.8% (group III). Hista mine concentration in oxyntic mucosal cells rose similarly. The size of the ECL cells was 8.5 +/- 0.1 mu m (control), 10.8 +/- 0.2 mu m (group II) and 12.1 +/- 0.2 mu m (group III), and the increased size was confirmed by shi fted distribution in elutriation fractions. Histamine per ECL cell increase d with cell size. The number of parietal cells increased parallel to the to tal number of mucosal cells (1.5-fold). Parietal cell size and percentage, assessed by image analysis and distribution in elutriation fractions, were unchanged after pantoprazole dosing. Gastrin has a pronounced, concentratio n-dependent specific trophic effect on ECL cells and a general proliferativ e effect on gastric mucosa, including parietal cells.