Human physiology . tudinal and transverse coats, thesynchronous activity of the two coats is seen to be altered by thepassage of a bolus introduced from the upper end. Fig. 82 records IV DIGESTION IN THE INTESTINE 245 this passage. The beginning of the tracings (left) shows therhythmic synchronous contractions of the longitudinal andcircular muscle-fibres. At A a bolus made of cotton-wool coatedwith vaseline was inserted by an opening into the intestine4i inches above the enterographs. The contractions of thecircular coat cease instantly, and this inhibition is accompaniedby a gradually increa
Human physiology . tudinal and transverse coats, thesynchronous activity of the two coats is seen to be altered by thepassage of a bolus introduced from the upper end. Fig. 82 records IV DIGESTION IN THE INTESTINE 245 this passage. The beginning of the tracings (left) shows therhythmic synchronous contractions of the longitudinal andcircular muscle-fibres. At A a bolus made of cotton-wool coatedwith vaseline was inserted by an opening into the intestine4i inches above the enterographs. The contractions of thecircular coat cease instantly, and this inhibition is accompaniedby a gradually increasing relaxation. There is some relaxationof the longitudinal coat, but the rhythmic contractions do notaltogether cease. At B the bolus had arrived at the upperlongitudinal lever, and at C had passed this, and was directlyunder the transverse enterograph or a little below it. At this pointa strong tonic contraction of both coats occurs, expelling the bolusbeyond the levers. This strong contraction passes off, to be. FIG. 82.—Passage of a bolus down the intestine, as recorded syiirlinninusly hy two enterographsat right angles. Longitudinal (L), circular (C), coats. (Bayliss and Starling.) (Explanationof letters in text.) succeeded by another, which like the first is moving down theintestine. In this second tonic wave the rhythmic contractionsare evident, superposed on the curve. After the passage of thebolus there is shortening of the gut (increased tone of longitudinalfibres), and the rhythmic contractions of each coat are no longersynchronous. Other valuable work has recently been carried out uponisolated loops of intestine. Salvioli (1882) had described andsuccessfully applied an admirable technique for studying thefunctions of parts of the intestine isolated from the animal. Hesucceeded in nourishing these loops by artificial circulation ofblood serum through the superior mesenterie artery. The in-testinal movements were recorded by very light levers placed indifferent pos
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectphysiology, bookyear1
