Chinese Journal of Physiology

44 H.C. HOU anp R. K. S, LIM

The diet consisted of a morning meal of 200 gm raw chopped beef and 100 cc water sometime between 10 and 11 a.m. and an evening meal of 300 gm of cooked corn meal and soy-bean flour (the former constituting two-thirds of the gruel) between 4 and 5 p.m. This regime was strictly adhered to during the week, but on Sundays the gruel was given at 12 p.m. with some amount of green vegetables. One litre of water was left with the animal from 4 p.m. to 8 a.m. the following morning,

Secretion was collected for two or three hours before giving the morning feed, and was continued for four hours afterwards. Several special procedures were applied but the secretion collected during and some days following these periods are not included in the present study. The figures given for the basal HCl secretion are the average ofstwo hourly periods, while those for the meal response are the average of the first four hours,

RESULTS

The frequency and range of acid secretion under basal conditions.

In the fistula-pouch, the frequency distribution is almost equally divided between the secretory groups given in table 1, and there is no instance of a rate above 20 mg HCl per hour, Thirty-one per cent of the rates observed fall below 1 mg HCl per hour, while the remainder is fairly evenly spread between 1 and 20 mg HCl.

In reversed and ‘‘non-reversed’’ Pavlov-pouches, secretion below 1 mg HCl per hour occurs more frequently (47 per cent) than in the fistula-pouch, while the frequency at higher rates falls off proportionately, although 3 per cent occur above 20 mg HCl per hour. The close similarity of the mean figures for the Pavlov-pouches is noteworthy for they differ in that one (the reversed) lacks either entirely or to a very great part vagal innervation; the difference between the fistulaand the simple Pavlov-pouch is purely quantitative in that the former is larger and retains a greater number of vagal and enteric connexions. Since no significant difference seems to exist between the basal behaviour of those pouches, we are lead to suspect that the vagus plays no particular réle in the maintenance of the basal secretion (although it is admitted that unrecognised conditioned or psychic reflexes may occur under basal conditions), The following experiment illustrates the vagus influence over the basal secretion in an individual animal.