On the mechanism of the physiological action of the cathartics

by John Bruce MacCallum

[25] Action of Medicines, 1867.

[26] Gazette Médicale, 1873.

[27] Journal of Anatomy and Physiology, Vol. XVI, 1882, and XVII, 1883.

[28] Arch. f. exp. Path. u. Pharm., Bd. 3, 1875, p. 215.

[29] MacCallum, J. B.: Journal of Exp. Zoology, Vol. I, No. 1, 1904. Preliminary Report, University of California Publications, Physiology, Vol. I, No. 10, p. 81, 1904.

[30] Arch. di Fisiologia, 1904, I, 413.

CHAPTER III.
The Local Application of Saline Solutions to the Peritoneal Surfaces of the Intestine.

In the last chapter it has been shown that the subcutaneous and intravenous injections of solutions of various saline purgatives produce a characteristic purgative effect; and that similar injections of calcium or magnesium chloride inhibit this action and bring the intestines to rest.

I have found also that solutions of these salts have the same effect when applied directly to the peritoneal surface of the intestine. Thus if a solution of sodium citrate or sulphate,[31] for example, be poured over the intestine those loops which are moistened by the solution will become active within one minute. After a very short time the remaining loops are also set in motion. These movements may be entirely inhibited by pouring on the loops a solution of calcium or magnesium chloride. The following description of these experiments is taken directly from my paper which appeared two years ago.[32]

The intestines of a rabbit under the influence of morphine were exposed. On a small group of coils there were poured 3 c.c. m/6 sodium citrate solution. Almost immediately (within 1 minute) the loops became very active. Strong contractions of the muscle coats took place. After a few minutes the other loops were also set in movement, so that the whole small intestine showed active peristalsis. The citrate solution was then washed off by m/6 NaCl solution, and about 3 c.c. m/6 CaCl₂ solution poured on the loops. The peristaltic movements were promptly suppressed, and the intestine remained quiet. By the further addition of citrate solution, the coils were set in active movement once more, and by the subsequent application of calcium chloride solution again inhibited. This was repeated many times (sixteen) and apparently might have been continued as long as the intestine remained alive.