Gastrointestinal handling of glycosyl [13C]ureides

Morrison, D.J., Dodson, B., Preston, T. and Weaver, L.T. (2003) Gastrointestinal handling of glycosyl [13C]ureides. European Journal of Clinical Nutrition, 57(8), pp. 1017-1024. (doi: 10.1038/sj.ejcn.1601637)

Full text not currently available from Enlighten.

Publisher's URL:


Objectives: Lactose [<sup>13</sup>C]ureide has been proposed as a noninvasive marker for oro-caecal transit time in adults and children. The present study investigates the handling of lactose [<sup>13</sup>C]ureide (<sup>13</sup>C LU) and glucose [<sup>13</sup>C]ureide (<sup>13</sup>C GU) by the gastrointestinal tract and describes the metabolic fates of these substrates and describes the extent of tracer excretion by different routes. Study Design and Subjects: Four subjects underwent five studies in which they ingested a test meal plus (1) no substrate, (2) <sup>13</sup>C LU, (3) <sup>13</sup>C GU, (4) <sup>13</sup>C LU after predosing with unlabelled lactose ureide and (5) <sup>13</sup>C LU after predosing with glucose ureide. Subjects were studied at home with at least 1 week between tests and they all completed the study. Breath was analysed for <sup>13</sup>CO2 recovery and urine was analysed for total 13C recovery, <sup>13</sup>C urea recovery and <sup>13</sup>C GU recovery. Results: The profiles and extent of tracer recovery in breath and urine were similar when either <sup>13</sup>C GU or <sup>13</sup>C LU was used, suggesting similar handling of these substrates by the gut. <sup>13</sup>C GU was the major <sup>13</sup>C-enriched species recovered in the urine even when <sup>13</sup>C LU was consumed. Predosing with either lactose ureide or glucose ureide increased the rate of appearance of tracer, but did not alter transit times. Conclusions: <sup>13</sup>C LU is hydrolysed to <sup>13</sup>C GU in the small intestine with the fraction of <sup>13</sup>C GU appearing in the urine probably limited by small intestinal permeability. Either <sup>13</sup>C LU or <sup>13</sup>C GU can be used to measure oro-caecal transit time.

Item Type:Articles
Glasgow Author(s) Enlighten ID:Preston, Professor Tom and Morrison, Dr Douglas
Authors: Morrison, D.J., Dodson, B., Preston, T., and Weaver, L.T.
Subjects:Q Science > QP Physiology
College/School:College of Science and Engineering > Scottish Universities Environmental Research Centre
Journal Name:European Journal of Clinical Nutrition

University Staff: Request a correction | Enlighten Editors: Update this record