THE RELEASE OF A HISTAMINE‐LIKE SUBSTANCE FROM THE LUNGS OF GUINEA‐PIGS DURING ANAPHYLACTIC SHOCK

Abstract

The claim made by Watanabe that the amount of gut‐contracting (guinea‐pig) substances present in guinea‐pig's lung extracts undergoes a large increase in animals sensitised 10–14 days previously, and also a large decrease after anaphylactic shock, has not been confirmed. Lung extracts prepared from batches of normal, sensitised and shocked animals show no detectable difference in their power to lower the blood‐pressure of the etherised and atropinised cat. In confirmation of Bartosch, Feldberg and Nagel, it has been found that a histamine‐like substance is released into the perfusate of isolated guinea‐pig's lungs during anaphylactic shock. Certain conditions governing the quantity of histamine‐like substance released during shock are described, and further evidence supporting the view that the substance is histamine is brought forward. A modified form of Einthoven's respiratory pump suitable for small animals is described. We are indebted to Dr. Raymond Williamson for advice in connection with the sensitisation of the animals, to Dr. Bayliss Ash for preparing the sheep serum and to Mr. H. F. Harding for making the drawing shown in fig. 1. The expenses of this research were in part defrayed by a grant to one of us (I. de B. D.) The Government Grant Committee of the Royal Society, to whom we express our thanks.