Histamine secretion in leukocyte incubates of patients with allergic hyperreactivity induced by somatostatin-14 and somatostatin-28.

Somatostatin is a potent histamine secretagogue found not only in rat mast cells but also in human leukocyte preparations. In concentrations greater than or equal to 5 mumol/l, somatostatin-14 induces histamine release, which correlates with the basophilic blood cell count, as shown in samples from allergic patients suffering from slight basophilia. Somatostatin-14 is twice as effective as somatostatin-28 on a molar basis, and acylating the tetradecapeptide with N-hydroxysuccinimidyl-p-hydroxy-phenyl-propionate decreases significantly the potency of histamine release.