When phenoltetrachlorphthalein is injected intravenously, it is eliminated from the body in the bile through the activity of the hepatic epithelium. The feces may be collected after purgation and the phthalein extracted and estimated against a standard solution. The estimation of phthalein can be done with accuracy in a suitable colorimeter and the elimination in normal dogs is quite constant.
Given a definite liver injury by means of poisons (chloroform, phosphorus), the amount of phthalein excreted will be diminished and the fall in output will be proportional to the amount of injury. With an acute fatal poisoning the curve may fall to zero.
Under certain conditions of vascular interference the liver phthalein may show a decreased output; in passive congestion of the liver and with the Eck fistula the liver output may fall considerably below normal.
Known disturbances of the liver function due to parenchymatous injury or vascular disturbances are indicated by a fall in the phthalein. excretion curve. Conversely it may be claimed that a drop in phthalein excretion may indicate a decrease in the functional capacity of the liver even if there be no detectable histological changes.
Adrenal insufficiency produced by extirpation of three fourths or more of the gland tissue will be associated with a drop in liver phthalein excretion. With hypertrophy of the adrenal fragment the excretion comes back to normal, but may fall again when more adrenal tissue is removed (text-figure 1).
Pancreatic insufficiency causes a progressive fall in the phthalein excretion indicating a grave lowering of the functional capacity of the liver (text-figure 2). This fact has a direct bearing on the question of diabetes.
Parathyroid insufficiency with tetany causes no decrease in phthalein output, but at times a rise above normal. This comes out best when the phthalein curve is low following pancreas extirpation. Parathyroid tetany may cause hyperactivity on the part of the liver cells.
Thyroid insufficiency produces no change in the uniform curve of phthalein excretion.
Hypophysis insufficiency shows an initial fall in the curve, followed by a return to normal and a final drop in the last few days before death.
These experiments supply evidence to the effect that the liver is very much concerned in the derangement that follows the removal of the ductless glands. Hence it seems probable that this disturbance of the liver function may be an important factor in the general symptom complex of ductless gland insufficiency.
In conclusion we wish to express our appreciation to Dr. S. J. Crowe and Dr. A. P. Jones for assistance rendered in performing some of the operations for gland removal.