Abstract
With regard to the relationship apparently existing between carbohydrate metabolism and the metabolism of phosphorus, it was proposed to study the behavior of the inorganic and the acid-soluble phosphorus in the blood of dogs whose carbohydrate supply was being rapidly utilized by strenuous exercise. The glycogen reserve of one series of animals was depleted by a preliminary 48 hour starvation.
The dogs were trained to run freely on a treadmill whose belt speed was 450 feet per minute. Rest periods at varying intervals during the exercise permitted the drawing of blood samples from the heart, and allowed the animals to regain their normal breathing. The total actual exercise varied from 30 minutes to 240 minutes.
The results from 10 experiments on 3 dogs showed:
1. Inorganic phosphorus in the blood of starved dogs taking standard exercise, at first decreased considerably (65 per cent in 90 minutes exercise), and then with continued exercise, rose towards the normal. During recovery, inorganic blood phosphorus rose to values approximately 60 per cent above normal. Total acid-soluble phosphorus of the blood paralleled its inorganic fraction during exercise and recovery. Sugar, calcium, and the percentage of corpuscles in the blood remained relatively constant.
2. Dogs that had not been starved showed very much less marked blood phosphoirus changes with exercise. (30 per cent initial decrease in 60 min. exercise.)
3. A given duration of exercise produced a definite inorganic phosphate concentration in the blood.
4. Changes in the concentration of blood inorganic phosphate during recovery from exercise were independent of the bration of exercise.
This is a preliminary report.
Get full access to this article
View all access options for this article.