STUDIES ON THE FILTRATION MECHANISM OF THE INTESTINAL LYMPH AND ON THE ACTION OF ACETYLCHOLINE ON IT AND ON THE CIRCULATION OF THE INTESTINAL VILLI

¹ The Institute of Physiology of the University at Budapest

1. Measurements of blood-pressure in the capillary, capillary veins, precapillary arteries of the intestinal villi of cats were carried out. The following values were found: blood-pressure in the precapillary 37·3, in the capillary 31·3, in the postcapillary 24·3 mm. Hg.

2. At the same time the colloid osmotic pressure of the blood serum of the mesenterial artery and vein gave values of 19·4 and 26·8 mm. Hg. respectively.

3. The pressure in the central lymph-vessel of the villus was also measured and found to be 24·5 mm. Hg.

4. The discussion of an individual case led to the conclusion that the hæmodynamical and osmotic pressure conditions in the villi are such as make filtration of the lymph possible.

5. The above values were estimated and recorded simultaneously before, during, and after the action of acetylcholine on the flow of lymph from the thoracic duct. The blood-pressure in the carotid artery was also recorded. The observation of Beznák that acetylcholine causes an increase of blood-pressure in the capillaries of the villi, which coincides with the fall of blood-pressure in the medium-sized arteries, is due to the relaxation of the precapillary arteries. Acetylcholine is regarded as a physiological lymph-producer.

The authors are particularly indebted to Professor A. B. L. Beznák for his helpful advice and criticism.