Acromegaly due to production of a growth hormone releasing factor by a bronchial carcinoid tumor.

We have studied growth hormone production in a patient with a bronchial carcinoid and acromegaly. The absence of growth hormone from the carcinoid tumour was demonstrated by extraction, cell culture and immunoperosidase techniques. Using a linked perfusion culture system, effluent from the bronchial carcinoid tumour culture stimulated a rapid release of growth hormone from a rat pituitary monolayer. This is the first time evidence of growth hormone releasing activity by a bronchial carcinoid has been demonstrated in a production.