Effect of glucagon on serum gastrin. II. Studies in pernicious anaemia and the Zollinger-Ellison syndrome.

Serum gastrin was measured by radioimmunoassay in four patients with pernicious anaemia and four patients with the Zollinger-Ellison syndrome before and after the intravenous injection of 1 mg glucagon. Serum gastrin fell significantly in the patients with pernicious anaemia whilst in the patients with the Zollinger-Ellison syndrome there was a significant rise. Concomitant measurement of gastric acid output in one subject with the Zollinger-Ellison syndrome also showed a rise in acid output with glucagon. The reason for the paradoxical rise in gastrin in response to glucagon in the Zollinger-Ellison syndrome is unknown, but the response may provide a further diagnostic aid to this condition.