Physiology and biochemistry in modern medicine . cotine. This local nervous system no doubt also resides in Auerbachsplexus, which must therefore be considered as complex enough to be (see THE MECHANISMS OP DIGESTION 467 page 796) endowed with the power of directing nervous impulses so as tol>riii.: about relaxation of the gu1 in front of ili<- stimulus and contrac-tion over it. Nervous Control op Movements The influence of the central nervous system on the intestinal movementshas been studied by the usual methods of cutting and stimulating theextrinsic nerve supply. Through the splanchn
Physiology and biochemistry in modern medicine . cotine. This local nervous system no doubt also resides in Auerbachsplexus, which must therefore be considered as complex enough to be (see THE MECHANISMS OP DIGESTION 467 page 796) endowed with the power of directing nervous impulses so as tol>riii.: about relaxation of the gu1 in front of ili<- stimulus and contrac-tion over it. Nervous Control op Movements The influence of the central nervous system on the intestinal movementshas been studied by the usual methods of cutting and stimulating theextrinsic nerve supply. Through the splanchnic nerves tonic inhibitoryimpulses are conveyed to the intestine (except the ileocolic sphincter),for after these nerves are severed the movements become more , in many animals after opening the abdomen no intestinal move-ment can be observed until these nerves have been cut. Stimulation of theperipheral end of the nerve also inhibits any movement which may mean-while be in progress. The impulses through the vagus nerve are of an. Fig. Ki3.—The effect of excitation of both splanchnic nerves on the intestinal contractions. (From Starling.) opposite character. Section of these nerves has little effect, but stimula-tion causes contraction. (Figs. 163 and 164.) By observing the rhythmic contractions of an isolated strip of the smallintestine suspended in a bath of oxygenated saline solution at body tem-perature, it can readily be shown that the presence of even a minute traceof epinephrine is sufficient to produce complete inhibition of the parallelism between the effects of splanchnic stimulation and those ofepinephrine injection is very significant, for in this way the marked inhi-bition of intestinal movement which occurs during fright may possiblybe explained (see page 736). The circular muscular coat of the last two or three centimenters ofthe ileum before it joins the cecum is definitely thicker than the rest ofthis coat, indicating that it has a
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