Changes in Upper Intestinal Epithelial Morphology and Kinetics in the Growing Guinea Pig

Abstract

ABSTRACT. Weaning, the process of intestinal adaptation from milk to solid diet, demands changes in gastrointestinal function. We aimed to measure upper intestinal mucosal morphology and cytokinetics during early life, to determine whether the marked changes seen at weaning in altricial species, such as rat and mouse also occur in the precocial guinea pig. A total of 79 animals was studied. Jejunal morphology was measured by microdissection and crypt cell production rate by a metaphase arrest technique in animals at 1, 7, 14, 21, and 28 days after birth. There was a 40% decline in villus height from 986 to 576 pm during

Mucosal surface area in chicken small intestine during development

“…Variations in villus height during development have often been reported for mammalian species, but contradictory conclusions reached; some authors have described an increase of this variable (Fry et al 1962;Holt et al 1984 in mouse and rat, respectively), no variations (Forrester 1972;Clarke 1977 in rat), and even a decrease with age (Warren 1939 in dog;Kapadia and Baker 1976;Hohn et al 1978 in rat;Weaver and Carrick 1989 in guinea pig). The present results of villus development, expressed as villus amplification factor, suggest significant regional differences during the period considered; the duodenum shows a peak in the third week of age (66% increase with respect to 1-day-old animals), after which it remains unchanged; the jejunum shows a progressive increase, and in the ileum this variable shows few changes.…”

A proposed intestinal mechanism for the effect of riboflavin deficiency on iron loss in the rat

“…The small intestinal mucosa may adapt to a wide variety of physiological and pathological stimuli, and the methods described here have been used to measure proliferative changes in many of these (Goodlad et ul. 1988;Weaver & Carrick, 1989). It is suggested that an increased rate of crypt cell proliferation in riboflavin deficiency leads to an accelerated rate of Fe loss via a change in the rate of cellular sloughing from the villus tip.…”

Ontogeny of Iron Uptake across Brush Border Membrane of Guinea Pig Duodenum and Its Autoradiographic Localisation

“…Important structural and functional changes occur as the enterocyte migrates along the villus [13], and a slower migration may lead to the earlier expression of absorp tive function. Recent work using guinea pig upper small intestine has demonstrated a slower epithelial turnover in newborn com pared to adult animals [14], Interestingly, conditions which slow cellular migration in adult rat intestine have been reported to enlarge the functional surface for active nu trient uptake [15,16], It is difficult to assess the contribution of the topographical difference in iron uptake in this present study to the increase in neo natal iron absorption reported earlier [1,2], Villus height and enterocyte column size are similar in adult and neonatal duodenum [2] suggesting, perhaps, a similar anatomical ab sorptive surface area. However, these mea surements are recognised to be a poor index of the total number of enterocytes making up the epithelium [17], particularly in the con text of developmental changes in villus shape reported elsewhere [18,19] and evi dent in this study ( fig.…”