Date Published: July 1, 2017
Publisher: American Physiological Society
Author(s): J. E. Dalziel, Karl Fraser, Wayne Young, Catherine M. McKenzie, Shalome A. Bassett, Nicole C. Roy.
This study reveals that the stress-prone Wistar-Kyoto rat strain has a baseline physiology of gastroparesis and rapid small intestine transit, together with metabolic changes consistent with lipid metabolism-associated dysbiosis, compared with nonstress-prone rats. This suggests that the Wistar-Kyoto rat strain may be an appropriate animal model for gastroparesis.
The main findings of this study are that stomach emptying was delayed in WKY compared with SD rats and that this delayed stomach emptying masked faster small intestinal transit in WKY compared with SD rats. This became evident once beads retained in the stomach were accounted for. Thus slower overall transit was a consequence of delayed stomach emptying. Stomach retention of beads was not due to the larger bead size relative to body weight in WKY rats because comparative experiments ruled this out. No difference was detected in large intestinal transit over 12 h in this study using the cecum as the reference location. This is consistent with a report that there is no difference in fecal output (or number of pellets) between nonstressed WKY and SD rats (21). Our supposition that the WKY rats are in the nonstressed state is supported by the similarly low corticosterone levels detected in both strains.
This study was funded by Strategic Science Investment Fund (Contract No. A21246) from AgResearch, Palmerston North, New Zealand.
No conflicts of interest, financial or otherwise, are declared by the authors.
J.E.D., K.F., W.Y., S.A.B., and N.C.R. conceived and designed research; J.E.D., K.F., and W.Y. performed experiments; J.E.D., K.F., W.Y., and C.M.M. analyzed data; J.E.D., K.F., and W.Y. interpreted results of experiments; J.E.D., K.F., and W.Y. prepared figures; J.E.D. drafted manuscript; J.E.D., K.F., W.Y., C.M.M., S.A.B., and N.C.R. edited and revised manuscript; J.E.D., K.F., W.Y., S.A.B., and N.C.R. approved final version of manuscript.