Xlvii. Studies upon the Mode of Action of Vitamin D Iv. the Absorption of Calcium Chloride, Xylose and Sodium Sulphate from Isolated Loops of the Small Intestine and of Calcium Chloride from the Abdominal Cavity in the Rat

Before the beginning of the experiment all the rats were kept without food overnight. The isolation of the loop was performed under ether narcosis. The mesenterium of the first 10-15 cm. of jejunum in rats weighing 70-120 g. is so short that measurement of the length of the loop is rather uncertain. A 30 cm. loop was isolated in each rat, starting about 15 cm. below the pylorus, and the lumen was rinsed out with 0 9% NaCl solution. The remaining fluid was pressed gently out between two fingers. The distal end was tied off, 3 ml. of the solution to be tested were injected into the lumen with a 3 ml. pipette and the proximal opening tied off. The loop was then replaced in the abdomen, the wall closed and the narcosis discontinued. After definite intervals the rats were killed by decapitation and the loops removed for analyses.