enterochromaffin like cell

Only enterochromaffin like cells with a visible nucleus were counted.

These tumours showed an exclusive or prominent enterochromaffin like cell population.

The enterochromaffin like cell density was determined in randomly selected fields.

According to our findings, hypergastrinaemia above a certain level will have the same trophic effect on the enterochromaffin like cells.

The enterochromaffin like cell density is expressed as number of cells per mm mucosal length.

In the rat, the enterochromaffin like cells produce and store most of the histamine in the oxyntic mucosa.

They found that patients with the highest serum gastrin concentrations did not necessarily have the highest enterochromaffin like cell counts.

It is generally accepted that gastrin controls the growth of the enterochromaffin like cells of the oxyntic mucosa.

The hypergastrinaemia and enterochromaffin like cell hyperplasia induced by these agents were abolished by antrectomy.

From the study of Larsson et al, it could appear that the number of enterochromaffin like cells would increase infinitely with the gastrin concentration.

In another study by Ryberg et al the enterochromaffin like cell labelling index was shown to increase linearly with the plasma gastrin concentration.

Hence, the dose response relationship for the trophic effect of gastrin on the enterochromaffin like cells seems to follow a polynominal rather than a linear function.

These findings may also contribute to the understanding of the trophic effect of gastrin on enterochromaffin like cells in man with conditions associated with hypergastinaemia.

There was no significant difference in enterochromaffin like cell density, histamine content or histidine decarboxylase activity between the groups receiving the three highest gastrin doses.

This may suggest that the histamine releasing and the trophic effects of gastrin on the enterochromaffin like cells are mediated by interaction with the same receptor.

For the first time a wide range dose response relationship for the trophic effect of gastrin on the enterochromaffin like cells of the rat stomach has been established.

Thus, profound inhibition of acid secretion by omeprazole or histamine 2 receptor blockers in the rat led to endogenous hypergastrinaemia and enterochromaffin like cell hyperplasia.

The present study was done to establish a dose response relationship for the trophic effect of gastrin on the enterochromaffin like cells by giving exogenous gastrin in graded doses.

In the rat this method can be regarded as specific for the enterochromaffin like cells, because the mast cells are few in the mucosa and restricted to the superficial layer.

These data may therefore indicate that when the gastrin concentration giving maximal trophic effect is reached, further growth of the enterochromaffin like cells id eependent on the duration of the hypergastrinaemia.

Furthermore, hypergastrinaemia after antrum exclusion or partial gastric corpectomy and exogenous hypergastrinaemia induced by continuous infusion of gastrin evoked proliferation of the enterochromaffin like cells in the rat stomach.

Hence, the histamine releasing and trophic effect of gastrin on the enterochromaffin like cells show about the same concentration dependence with regard to the minimal concentration of gastrin causing maximal effect.

Gastrin induced a dose dependent increase in enterochromaffin like cell density, oxyntic mucosal histamine concentration and histidine decarboxylase activity up to the dose of 5 m g/ kg/h, where the increase levelled off.

The linear relationship between plasma gastrin concentration and the enterochromaffin like cell density previously reported may only reflect a more prolonged endogenous hypergastrinaemia in those with the highest gastrin concentration two hours after administration of the drug.

In conclusion, the present study indicates that there is an increasing enterochromaffin like cell density with increasing gastrin concentration up to a certain level, and increasing the gastrin concentration above this level does not lead to further hyperplasia.