A text-book of physiology for medical students and physicians (1911) (14776961804)

Identifier: textbookofphysio1911howe (find matches)
Title: A text-book of physiology for medical students and physicians
Year: 1911 (1910s)
Authors: Howell, William H. (William Henry), 1860-1945
Subjects: Physiology
Publisher: Philadelphia, London, W.B. Saunders company
Contributing Library: Columbia University Libraries
Digitizing Sponsor: Open Knowledge Commons



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crete an alkaline liquidcontaining pepsin, and, according to Edkins and Starling thevform a substance which is capable of acting as a chemical excitant * See Haane, Archiv f. Anatomie, 1905, 1.t Griitzner, Archiv f. die gesammte Physiologic, 106, 463, 1905. 756 DIGESTION AND ABSORPTION IN THE STOMACH. 757 to the glands secreting the gastric juice (gastric secretin or gastrichormone) .* Histological Changes in the Gastric Glands during Secretion.—The cells of the gastric glands, especially the so-called chief cells,show distinct changes as the result of prolonged activity. Uponpreserved specimens, taken from dogs fed at intervals of twenty-fourhours, Heidenhain found that in the fasting condition the chief cellswere large and clear, that during the first six hours of digestion thechief cells as well as the border cells increased in size, but that in asecond period, extending from the sixth to the fifteenth hour, thechief cells became gradually smaller, while the border cells remained
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Fig. 293.—Glands of the fundus (dog): A and A1, during hunger, resting condition;B, during the first stage of digestion; C and D, the second stage of digestion, showingihe diminution in the size of the chief or central cells.—(After Heidenhain.) large or even increased in size. After the fifteenth hour the chiefcells increased in size, gradually passing back to the fasting condition(see Fig. 293). Langley * has succeeded in following the changes in a more satis-factory way by observations made directly upon the living gland. * See-Starling, Physiology of Secretion, Chicago, 1906, and Edkins,Journal of Physiology, 1906, xxxiv., 133.t Journal of Physiology/ 3, 269, 1880. 758 PHYSIOLOGY OF DIGESTION AND SECRETION. He finds that the chief cells in the fasting stage are charged withgranules, and that during digestion the granules are dissolved, dis-appearing first from the base of the cell, which then becomes filledwith a non-granular material. Observations similar to those madeupon ot