The effect of cromolyn sodium on hypoxia-induced histamine release

In 16 guinea pigs the pulmonary circulation was isolated from the pulmonary systemic circulation and perfused with Tris buffer or with Tris buffer containing cromolyn sodium. The lungs were first ventilated with 100% O2 and then 100% N2 to induce alveolar hypoxia. The effluent was collected from the aorta and assayed for histamine by the fluorometric method. In all seven animals perfused with Tris alone (no cromolyn) a marked elevation of the effluent histamine was demonstrated. In the group perfused with buffer containing cromolyn there was a substantial diminution in the response to hypoxia. Therefore, cromolyn sodium partially blocked hypoxia-mediated histamine release.