Small intestinal length: a factor essential for gut adaptation.

Abstract

Changes in small intestinal structure, cytokinetics, and function are dynamic ways in which the gut adapts to diet, disease, and damage. Adequate length provides a static 'reserve' permitting an immediate response to pathophysiological changes. The length of the small intestine from conception to adulthood using data taken from eight published reports of necropsy measurement of 1010 guts is described. Mean The lengths of 1010 specimens were plotted against the lengths or heights of the subjects. All length measurements were converted to cm. To establish the relation between intestinal length and body length or height, the data were fitted by cubic spline regression." To deal with the mixture of individual and grouped data in the sample, each point in the analysis was given a weighting corresponding to the number of individuals contained in it: 1 for individuals and n for groups of size n. The spline curve was fitted to both the original data and to the log transformed data. In the latter case, the slope of the regression curve indicated the power relation between small intestinal length and body length. The small intestine is the major site of nutrient and water absorption. To ensure an adequate surface area to meet the nutritional requirements of the organism, it is a long coiled organ whose epithelial surface is increased many times by circular folds, villi, and microvilli.'For most mammals there is a direct relation between the gross surface area of the small intestine and body size. This is related to the diet eaten by each species, and for man it conforms with that of other members of the superfamily (Fig 1).Growth in intestinal length continued during early postnatal life, but from about 1 year (75 cm body length) onwards it slowed and remained linear with increasing age to adulthood. From birth there was a wide range in intestinal lengths reported, with 100% variation from early childhood onwards. The coefficient of variation of small intestinal length postnatally was 24%, sixfold greater than for body length. Figure 2 shows the corresponding results and spline curve obtained after log transformation of the data. The pre-and perinatal acceleration in length is clearly seen. In proportional terms, prenatal growth in small intestinal length was consistently faster than that of body length, increasing as the power law small intestinal length a body length to the power 4/3. After birth there was a noticeable deceleration in small intestinal length growth, so that it was less than 1321 on 12 May 2018 by guest. Protected by copyright.

Surface area assessment of the murine intestinal tract as a prerequisite for oral dose translation from mouse to man

“…In humans, the length of the small and large intestines are approximately 7 and 1.5 m, respectively. 17,18 The human jejunum and ileum have an equal length of approximately 3 m. 17 In contrast, the murine jejunum is much longer than the ileum since the latter segment is defined as the terminal transverse part of the murine small intestine. 3 The relative proportions of the small and large intestines are, however, similar in humans and mice (approximately 80% and 20%).…”

Jun N-terminal kinase maintains tissue integrity during cell rearrangement in the gut

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Congenital short bowel syndrome as the presenting symptom in male patients with FLNA mutations

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