Mathes Clare M, Bohnenkamp Ryan A, le Roux Carel W, Spector Alan C
Department of Psychology and Program in Neuroscience, Florida State University, Tallahassee, Florida;
Diabetes Complications Research Centre, School of Medicine and Medical Science, University College Dublin, Dublin, Ireland; Investigative Medicine, Imperial College London, London, United Kingdom; and Gastrosurgical Laboratory, University of Gothenburg, Gothenburg, Sweden.
Am J Physiol Regul Integr Comp Physiol. 2015 Oct 15;309(8):R864-74. doi: 10.1152/ajpregu.00029.2015. Epub 2015 Aug 19.
Here we assessed how intake reductions induced by Roux-en-Y gastric bypass surgery (RYGB) occur within and across access periods by examining drinking microstructure. After training, RYGB (n = 8-10) or sham-operated (SHAM, n = 12) rats were given 60-min access first to 0.3 M sucrose, then to 5% Intralipid, and finally to milk-chocolate Ensure Plus across 5 days each. Initially, total licks taken during the first meal of sucrose and Intralipid by RYGB and SHAM rats did not differ, but, across subsequent test periods, RYGB rats licked less than SHAM rats. First Ensure meal size also did not differ between RYGB and SHAM rats, but SHAM rats increased licking across test periods while the behavior of RYGB rats remained stable. The intake differences between the surgical groups, when they occurred, were most often due to smaller burst sizes in RYGB rats. Importantly, the surgical-group difference in sucrose and Intralipid intakes could not be explained by altered palatability of these solutions because, throughout testing, both groups had similar early meal licking behavior thought to represent the motivational potency of stimulus orosensory features. Although, overall, RYGB rats displayed lower early meal licking of Ensure relative to the SHAM rats, this appeared to be driven primarily by increases in the latter group across test periods; the RYGB group stayed relatively stable. Collectively, these results suggest that some level of postoral experience with these stimuli and/or their components is necessary before intake differences emerge between surgical groups, and, even when differences occur, often immediate taste-motivated ingestive behavior remains unaltered.
在此，我们通过检查饮水微观结构，评估了Roux-en-Y胃旁路手术（RYGB）引起的摄入量减少在进食期内以及不同进食期之间是如何发生的。训练后，给RYGB组（n = 8 - 10）或假手术组（SHAM，n = 12）的大鼠分别在5天内，每次给予60分钟时间，先饮用0.3M蔗糖溶液，然后饮用5%的脂肪乳剂，最后饮用牛奶巧克力Ensure Plus。最初，RYGB组和SHAM组大鼠在蔗糖和脂肪乳剂第一餐期间的总舔舐次数没有差异，但在随后的测试期内，RYGB组大鼠的舔舐次数少于SHAM组大鼠。RYGB组和SHAM组大鼠在Ensure第一餐的摄入量也没有差异，但SHAM组大鼠在测试期内舔舐次数增加，而RYGB组大鼠的行为保持稳定。手术组之间的摄入量差异出现时，最常见的原因是RYGB组大鼠的单次舔舐量较小。重要的是，手术组在蔗糖和脂肪乳剂摄入量上的差异不能用这些溶液适口性的改变来解释，因为在整个测试过程中，两组在早期进食时的舔舐行为相似，这种行为被认为代表了刺激口腔感觉特征的动机强度。尽管总体而言，相对于SHAM组大鼠，RYGB组大鼠在Ensure早期进食时的舔舐较少，但这似乎主要是由后一组在测试期内的增加所驱动；RYGB组保持相对稳定。总的来说，这些结果表明，在手术组之间出现摄入量差异之前，需要一定程度的对这些刺激物和/或其成分的口后体验，而且即使出现差异，通常即时的味觉驱动摄食行为仍未改变。
