Summary
Factor VIII increase after stress or adrenergic stimulation appears to be justified
by ACTH release, which in turn liberates a principle other than steroids, from the
adrenal cortex. A substance isolated from adrenal cortex and denominated S3 increase,
when injected, the level of plasma factor VIII. The rise in factor VIII after S3 also
occurs in adrenalectomized animals where ACTH or catecholamines administration gives
negative results.