THE EFFECT OF DIGESTION ON THE BLOOD FLOW IN CERTAIN BLOOD VESSELS OF THE DOG

Publisher Website
Google Scholar
Abstract
Observations on the influence of the digestion of food on the blood flow in the femoral, carotid, and mesenterie. arteries and the external jugular vein show that, contrary to current belief, the blood is not diverted from the somatic tissue to the visceral organs during digestion. Instead of a decrease in blood flow in the arteries named and the jugular vein, there is a marked, prolonged increase during the digestive cycle. The time of onset and the duration of the increased flow are influenced by the character of the food, but the magnitude is about the same regardless of the type of food ingested. In general, the highest values for blood flow obtained during digestion are ca. twice those obtained after an 18-hr. fast. The initial increase in blood flow following a semifluid meal rich in carbohydrate occurs more rapidly (10-20 min.) than that following a lean meat meal, after which a lapse of as much as 3 hrs. may occur. The addition of water to the meat meal causes an increase in blood flow 10-20 min. after the food is ingested, lasting 2-6 hrs., and is accompanied by an increase in pulse and respiratory rates; it is not apparently due to a reflex vasomotor mechanism, since changes in volume of limbs in man and the dog were not observed following the ingestion of food. Significant changes in surface temp. were not found. The effect of food on the blood flow in the femoral artery of dogs on which lumbar sympathectomy had previously been performed was comparable to that observed in intact dogs after eating. Significant changes in the blood volume were not apparent by use of the dye method. The increase in blood flow following a meal is accompanied by an elevation in pulse rate and probably in cardiac output and, simultaneously, there is a shorter circulation time. The increase in pulse rate does not appear to be due to mechanical causes. The increase in blood flow may be due to the specific dynamic action of the food, a product of digestion, such as a secretagogue, or to a hormone elaborated by the digestive tract.

This publication has 0 references indexed in Scilit: