Abstracts 1998 Digestive Disease Week
#980
INTESTINAL TRANSPLANTS SHOW IMPAIRED REGULATION OF TRANSIT IN SHORT GUT SYNDROME. C.P. Johnson, S.K. Sarna, Y.R. Zhu, G. Telford, A.M. Roza, M.B. Adams, Departments of Transplant Surgery and General Surgery. Milwaukee, Wisconsin.
Postprandial motility of the transplanted intestine has not been studied in detail. Furthermore, it is not known whether important adaptive changes such as delayed gastric emptying (GE) and reduced intestinal transit rate can occur. The purpose of this study was to examine motor function and regulation of intestinal transit in a canine model of transplantation and short gut syndrome (SGS). Methods: Animals (n=22) were instrumented with strain gauge transducers, collection cannulae and an infusion catheter to measure postprandial motility, intestinal flow and transit rates, and GE. Ten animals served as controls to define normal parameters. Six animals underwent 70% resection of proximal small intestine to serve as SGS controls. Six animals underwent removal of a 100cm segment of ileum, overnight cold storage and autotransplantation the following day along with a 70% resection of proximal bowel (TXP). Identical segments of ileum were analyzed at 2 and 6 weeks using computer programs that determine frequency, amplitude and propagation behavior for circular smooth muscle contractions. Intestinal flow and transit rates were measured using perfusion or bolus injections of 3H-PEG. GE was determined as the time to empty 95% of a 14C-PEG labeled meal. Data (mean ± SEM) were analyzed by ANOVA (Tukey Test). Results: Data were similar at 2 and 6 weeks with 2 weeks shown below:
Parameter
|
Control
|
SGS
|
TXP
|
Contraction freq. (#/min)
|
13.6 ± 0.8
|
9.8 ± 0.5a
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10.2 ± 0.5a
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Mean amplitude (g)
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20.9 ± 1.5
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21.9 ± 3.8
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22.3 ± 2.6
|
Propagating area/min (g.sec/min)
|
368 ± 28
|
283 ± 65
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282 ± 26
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Transit rate (cm/min)
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4.8 ± 0.7
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2.0 ± 0.3a
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4.8 ± 0.4b
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Intestinal flow rate (ml/min)
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6.2 ± 0.6
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3.3 ± 0.5a
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2.5 ± 0.4a
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GE rate (min)
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307 ± 17
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467 ± 21a
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419 ± 38a
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ap < .05 vs. control, bp < .05 vs. SGS
Conclusion: Both SGS and TXP animals display delayed GE and reduced intestinal flow rates which are adaptive responses. In TXP animals, the postprandial motor response is comparable to SGS controls, but the ability to slow intestinal transit is lost. This cannot be explained by a change in amplitude or propagation of circular smooth muscle contractions, but could be due to a change in tone (i.e. impaired relaxation) related to denervation or ischemic injury.
Copyright 1996 - 1998, SSAT, Inc. Revised 29 June 1998.
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