THE EFFECT OF CERTAIN PATHOLOGICAL SERA ON PLAIN MUSCLE

¹ The Physiology Department, University of Edinburgh

1. Normal human serum contains a substance which causes a constant rise in tone when applied to plain muscle.

2. A similar rise in tone was obtained with serum from cases of diabetes, scarlet fever, diphtheria (convalescent), pernicious anæmia, syphilis, and some cases of nephritis, malignant disease, and afebrile tuberculosis.

3. An increased effect was obtained with serum from exophthalmic goitre, febrile tuberculosis, six out of eight cases of malignant disease, six out of nine cases of nephritis, and one case of influenza.

4. A less marked rise of tone occurred with serum from one case of myxdema, and was increased up to normal after thyroid-feeding.

5. The augmentor substance occurs in serum, citrated blood, citrated plasma, laked, washed red cells, and fresh uncoagulated blood.

I desire to express my thanks to Professor Meakins, Professor Lovell Gulland, Professor Sir Harold Stiles, and Dr Lees of the Royal Infirmary for facilities given for obtaining material ; also to Dr Crockett of the Bridge of Weir Sanatoria and Dr Simpson of Southfields Sanatorium.

The expenses of this research have been partly defrayed by a grant from the Earl of Moray Research Endowment Fund.