Marco Bueter and Florian Seyfried were supported by the Deutsche Forschungsgemeinschaft (DFG). Thomas A Lutz was supported by the Swiss National Research Foundation (SNF). Marco Bueter and Thomas A Lutz further receive funding from the National Institute of Health (NIH) and from the Zurich Center for Integrative Human Physiology (ZIHP). Carel W le Roux was supported by a Department of Health Clinician scientist award. Imperial College London receives support from the NIHR Biomedical Research Centre funding scheme.

1. Preoperative Care
<ol>
	<li>Remove food from rat overnight prior to surgery.</li>
	<li>Induce anaesthesia in chamber with 4-5% isoflurane and O2 flow of 2 l/min.</li>
	<li>Shave abdomen from sternum to pelvis using electric razor.</li>
	<li>Place anaesthetised rat in supine position on isothermal heating pad.</li>
	<li>Apply eye ointment (Vitagel) before placing the rats' snout in nosecone.</li>
	<li>Maintain anaesthesia with isoflurane concentration of 2-3% and O2 flow of 2 l/min.</li>
	<li>Disinfect skin with Beta...

<ol>
	<li>Adams, T. D., Gress, R. E., Smith, S. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Long-term+mortality+after+gastric+bypass+surgery.">Long-term mortality after gastric bypass surgery.</a> N. Engl. J. Med. 357, 753-761 (2007).</li><li>Sjostrom, L., Lindroos, A. K., Peltonen, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Lifestyle,+diabetes,+and+cardiovascular+risk+factors+10+years+after+bariatric+surgery.">Lifestyle, diabetes, and cardiovascular risk factors 10 years after bariatric surgery.</a> N. Engl. J. Med. 351, 2683-2693 (2004).</li><li>Buchwald, H., Oien, D. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Metabolic/bariatric+surgery+Worldwide.">Metabolic/bariatric surgery Worldwide.</a> Obes. Surg. 19, 1605-1611 (2008).</li><li>Welbourn, R., Werling, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Gut+hormones+as+mediators+of+appetite+and+weight+loss+after+Roux-en-Y+gastric+bypass.">Gut hormones as mediators of appetite and weight loss after Roux-en-Y gastric bypass.</a> Ann. Surg. 246, 780-785 (2007).</li><li>le Roux, C. W., Aylwin, S. J., Batterham, R. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Gut+hormone+profiles+following+bariatric+surgery+favor+an+anorectic+state,+facilitate+weight+loss,+and+improve+metabolic+parameters.">Gut hormone profiles following bariatric surgery favor an anorectic state, facilitate weight loss, and improve metabolic parameters.</a> Ann. Surg. 243, 108-114 (2006).</li><li>Bueter, M., Lowenstein, C., Olbers, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Gastric+bypass+increases+energy+expenditure+in+rats.">Gastric bypass increases energy expenditure in rats.</a> Gastroenterology. 138, 1845-1853 (2010).</li><li>Stylopoulos, N., Hoppin, A. G., Kaplan, L. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Roux-en-Y+Gastric+Bypass+Enhances+Energy+Expenditure+and+Extends+Lifespan+in+Diet-induced+Obese+Rats.">Roux-en-Y Gastric Bypass Enhances Energy Expenditure and Extends Lifespan in Diet-induced Obese Rats.</a> Obesity (Silver Spring). 17, 1839-1847 (2009).</li><li>Bueter, M., Miras, A. D., Chichger, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Alterations+of+sucrose+preference+after+Roux-en-Y+gastric+bypass.">Alterations of sucrose preference after Roux-en-Y gastric bypass.</a> Physiol. Behav. 104, 709-721 (2011).</li><li>le Roux, C. W., Bueter, M., Theis, N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Gastric+bypass+reduces+fat+intake+and+preference.">Gastric bypass reduces fat intake and preference.</a> Am. J. Physiol. Regul. Integr. Comp. Physiol. 301, 1057-1066 (2011).</li><li>Bueter, M., Ashrafian, H., Frankel, A. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Sodium+and+water+handling+after+gastric+bypass+surgery+in+a+rat+model.">Sodium and water handling after gastric bypass surgery in a rat model.</a> Surg. Obes. Relat. Dis. 7, 68-73 (2011).</li><li>Li, J. V., Ashrafian, H., Bueter, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Metabolic+surgery+profoundly+influences+gut+microbial-host+metabolic+cross-talk.">Metabolic surgery profoundly influences gut microbial-host metabolic cross-talk.</a> Gut. 60, 1214-1223 (2011).</li><li>Ashrafian, H., le Roux, C. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Metabolic+surgery+and+gut+hormones+-+a+review+of+bariatric+entero-humoral+modulation.">Metabolic surgery and gut hormones - a review of bariatric entero-humoral modulation.</a> Physiol. Behav. 97, 620-631 (2009).</li><li>Ashrafian, H., Bueter, M., Ahmed, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Metabolic+surgery:+an+evolution+through+bariatric+animal+models.">Metabolic surgery: an evolution through bariatric animal models.</a> Obes. Rev. 11, 907-920 (2010).</li><li>Rao, R. S., Rao, V., Kini, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Animal+models+in+bariatric+surgery--a+review+of+the+surgical+techniques+and+postsurgical+physiology.">Animal models in bariatric surgery--a review of the surgical techniques and postsurgical physiology.</a> Obes. Surg. 20, 1293-1305 (2010).</li><li>Seyfried, F., le Roux, C. W., Bueter, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Lessons+learned+from+gastric+bypass+operations+in+rats.">Lessons learned from gastric bypass operations in rats.</a> Obes. Facts. 4, 3-12 (2011).</li><li>Fenske, W. K., Bueter, M., Miras, A. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Exogenous+peptide+YY3-36+and+Exendin-4+further+decrease+food+intake,+whereas+octreotide+increases+food+intake+in+rats+after+Roux-en-Y+gastric+bypass.">Exogenous peptide YY3-36 and Exendin-4 further decrease food intake, whereas octreotide increases food intake in rats after Roux-en-Y gastric bypass.</a> Int. J. Obes. (Lond). , (2011).</li><li>Kreymann, B., Williams, G., Ghatei, M. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Glucagon-like+peptide-1+7-36:+a+physiological+incretin+in+man.">Glucagon-like peptide-1 7-36: a physiological incretin in man.</a> Lancet. 2, 1300-1304 (1987).</li><li>le Roux, C. W., Batterham, R. L., Aylwin, S. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Attenuated+peptide+YY+release+in+obese+subjects+is+associated+with+reduced+satiety.">Attenuated peptide YY release in obese subjects is associated with reduced satiety.</a> Endocrinology. 147, 3-8 (2006).</li><li>Torres, J. C., Oca, C. F., Garrison, R. N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Gastric+bypass:+Roux-en-Y+gastrojejunostomy+from+the+lesser+curvature.">Gastric bypass: Roux-en-Y gastrojejunostomy from the lesser curvature.</a> South Med. J. 76, 1217-1221 (1983).</li><li>Guijarro, A., Suzuki, S., Chen, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Characterization+of+weight+loss+and+weight+regain+mechanisms+after+Roux-en-Y+gastric+bypass+in+rats.">Characterization of weight loss and weight regain mechanisms after Roux-en-Y gastric bypass in rats.</a> Am. J. Physiol. Regul. Integr. Comp. Physiol. 293, R1474-R1489 (2007).</li><li>Roberts, K., Duffy, A., Kaufman, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Size+matters:+gastric+pouch+size+correlates+with+weight+loss+after+laparoscopic+Roux-en-Y+gastric+bypass.">Size matters: gastric pouch size correlates with weight loss after laparoscopic Roux-en-Y gastric bypass.</a> Surg. Endosc. 21, 1397-1402 (2007).</li><li>Hajnal, A., Kovacs, P., Ahmed, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Gastric+bypass+surgery+alters+behavioral+and+neural+taste+functions+for+sweet+taste+in+obese+rats.">Gastric bypass surgery alters behavioral and neural taste functions for sweet taste in obese rats.</a> Am. J. Physiol. Gastrointest. Liver Physiol. 299, G967-G979 (2010).</li><li>Shin, A. C., Zheng, H., Pistell, P. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Roux-en-Y+gastric+bypass+surgery+changes+food+reward+in+rats.">Roux-en-Y gastric bypass surgery changes food reward in rats.</a> Int. J. Obes. (Lond). 35, 642-651 (2011).</li><li>Tichansky, D. S., Rebecca, G. A., Madan, A. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Decrease+in+sweet+taste+in+rats+after+gastric+bypass+surgery.">Decrease in sweet taste in rats after gastric bypass surgery.</a> Surg. Endosc. 25, 1176-1181 (2011).</li><li>Olbers, T., Lonroth, H., Fagevik-Olsen, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Laparoscopic+gastric+bypass:+development+of+technique,+respiratory+function,+and+long-term+outcome.">Laparoscopic gastric bypass: development of technique, respiratory function, and long-term outcome.</a> Obes. Surg. 13, 364-370 (2003).</li><li>Madan, A. K., Harper, J. L., Tichansky, D. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Techniques+of+laparoscopic+gastric+bypass:+on-line+survey+of+American+Society+for+Bariatric+Surgery+practicing+surgeons.">Techniques of laparoscopic gastric bypass: on-line survey of American Society for Bariatric Surgery practicing surgeons.</a> Surg. Obes. Relat. Dis. 4, 166-172 (2008).</li><li>Bueter, M., Lowenstein, C., Ashrafian, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Vagal+sparing+surgical+technique+but+not+stoma+size+affects+body+weight+loss+in+rodent+model+of+gastric+bypass.">Vagal sparing surgical technique but not stoma size affects body weight loss in rodent model of gastric bypass.</a> Obes. Surg. 20, 616-622 (2010).</li><li>Korner, J., Bessler, M., Cirilo, L. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effects+of+Roux-en-Y+gastric+bypass+surgery+on+fasting+and+postprandial+concentrations+of+plasma+ghrelin,+peptide+YY,+and+insulin.">Effects of Roux-en-Y gastric bypass surgery on fasting and postprandial concentrations of plasma ghrelin, peptide YY, and insulin.</a> J. Clin. Endocrinol. Metab. 90, 359-365 (2005).</li><li>Schwartz, M. W., Woods, S. C., Porte, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Central+nervous+system+control+of+food+intake.">Central nervous system control of food intake.</a> Nature. 404, 661-671 (2000).</li><li>Abbott, C. R., Monteiro, M., Small, C. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+inhibitory+effects+of+peripheral+administration+of+peptide+YY(3-36)+and+glucagon-like+peptide-1+on+food+intake+are+attenuated+by+ablation+of+the+vagal-brainstem-hypothalamic+pathway.">The inhibitory effects of peripheral administration of peptide YY(3-36) and glucagon-like peptide-1 on food intake are attenuated by ablation of the vagal-brainstem-hypothalamic pathway.</a> Brain Res. 1044, 127-131 (2005).</li><li>Adrian, T. E., Ballantyne, G. H., Longo, W. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Deoxycholate+is+an+important+releaser+of+peptide+YY+and+enteroglucagon+from+the+human+colon.">Deoxycholate is an important releaser of peptide YY and enteroglucagon from the human colon.</a> Gut. 34, 1219-1224 (1993).</li><li>Nakatani, H., Kasama, K., Oshiro, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Serum+bile+acid+along+with+plasma+incretins+and+serum+high-molecular+weight+adiponectin+levels+are+increased+after+bariatric+surgery.">Serum bile acid along with plasma incretins and serum high-molecular weight adiponectin levels are increased after bariatric surgery.</a> Metabolism. 58, 1400-1407 (2009).</li><li>Ashrafian, H., le Roux, C. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Metabolic+surgery+and+gut+hormones+-+a+review+of+bariatric+entero-humoral+modulation.">Metabolic surgery and gut hormones - a review of bariatric entero-humoral modulation.</a> Physiol. Behav. 97, 620-631 (2009).</li><li>Choban, P. S., Flancbaum, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+effect+of+Roux+limb+lengths+on+outcome+after+Roux-en-Y+gastric+bypass:+a+prospective,+randomized+clinical+trial.+Obes.">The effect of Roux limb lengths on outcome after Roux-en-Y gastric bypass: a prospective, randomized clinical trial. Obes.</a> Surg. 12, 540-545 (2002).</li><li>Gleysteen, J. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Five-year+outcome+with+gastric+bypass:+Roux+limb+length+makes+a+difference.">Five-year outcome with gastric bypass: Roux limb length makes a difference.</a> Surg. Obes. Relat. Dis. 5, 242-247 (2009).</li><li>Lee, S., Sahagian, K. G., Schriver, J. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Relationship+between+varying+Roux+limb+lengths+and+weight+loss+in+gastric+bypass.">Relationship between varying Roux limb lengths and weight loss in gastric bypass.</a> Curr. Surg. 63, 259-263 (2006).</li><li>Hayes, M. R., Kanoski, S. E., De Jonghe, B. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+common+hepatic+branch+of+the+vagus+is+not+required+to+mediate+the+glycemic+and+food+intake+suppressive+effects+of+glucagon-like-peptide-1.">The common hepatic branch of the vagus is not required to mediate the glycemic and food intake suppressive effects of glucagon-like-peptide-1.</a> Am. J. Physiol. Regul. Integr. Comp. Physiol. 301, R1479-R1485 (2011).</li></ol>

No conflicts of interest declared.

The Roux-en-Y gastric bypass procedure in humans was first described by Mason in 1967 and modified to its current form by Torres in 198319. Currently, the procedure consists of a small gastric pouch and the bypass of the proximal small bowel. A schematic illustration of the pre- and postoperative anatomy is given in Figure 1.
Gastric bypass in humans induces and maintains body weight loss of approximately 15-30%2. The majority of body weight is lost durin...

<table border="1">
	<tbody>
		<tr>
			<td>Generic name</td>
			<td>Brand name</td>
			<td>Company</td>
			<td>Catalogue number</td>
		</tr>
		<tr>
			<td>Enrofloxacin</td>
			<td>Baytril 2.5%</td>
			<td>Provet AG</td>
			<td>1036</td>
		</tr>
		<tr>
			<td>Flunixin</td>
			<td>Finadyne</td>
			<td>Graeub</td>
			<td>908040</td>
		</tr>
		<tr>
			<td>Buprenorphin</td>
			<td>Temgesic</td>
			<td>Reckitt Benckiser</td>
			<td>138976</td>
		</tr>
		<tr>
			<td>Isoflurane</td>
			<td>IsoFlo</td>
			<td>Graeub</td>
			<td>902035</td>
		</tr>
		<tr>
			<td>Vitamin A</td>
			<td>Vitagel</td>
			<td>Bausch &amp; Lomb</td>
			<td>690</td>
		</tr>
		<tr>
			<td>Iodine solution</td>
			<td>Betadine</td>
			<td>Mundipharma</td>
			<td>111141</td>
		</tr>
		<tr>
			<td>NaCl 0.9%</td>
			<td>NaCl 0.9%</td>
			<td>B. Braun</td>
			<td>534534</td>
		</tr>
	</tbody>
</table>
Table 1. Drugs.
<table border="1">
	<tbody>
		<tr>
			<td>Name</td>
			<td>Size</td>
			<td>Company</td>
			<td>Catalogue number</td>
		</tr>
		<tr>
			<td>PDS II</td>
			<td>4-0</td>
			<td>Ethicon</td>
			<td>Z924H</td>
		</tr>
		<tr>
			<td>PDS II</td>
			<td>5-0</td>
			<td>Ethicon</td>
			<td>Z925H</td>
		</tr>
		<tr>
			<td>PDS II</td>
			<td>6-0</td>
			<td>Ethicon</td>
			<td>PUU2971E</td>
		</tr>
		<tr>
			<td>PDS II</td>
			<td>7-0</td>
			<td>Ethicon</td>
			<td>Z1370E</td>
		</tr>
		<tr>
			<td>Vicryl</td>
			<td>4-0</td>
			<td>Ethicon</td>
			<td>V451H</td>
		</tr>
	</tbody>
</table>
Table 2. Sutures.
<table border="1">
	<tbody>
		<tr>
			<td>Name</td>
			<td>Company</td>
			<td>Catalogue number</td>
		</tr>
		<tr>
			<td>Scalpel handle No. 3</td>
			<td>Aesculap</td>
			<td>BB073R</td>
		</tr>
		<tr>
			<td>Scalpel blades No. 10</td>
			<td>Swann-Morton</td>
			<td>0301</td>
		</tr>
		<tr>
			<td>Needle holder</td>
			<td>Aesculap</td>
			<td>BM124R</td>
		</tr>
		<tr>
			<td>Tissue forceps</td>
			<td>Aesculap</td>
			<td>BD555R</td>
		</tr>
		<tr>
			<td>Metzenbaum scissors, straight</td>
			<td>Aesculap</td>
			<td>BC022R</td>
		</tr>
		<tr>
			<td>Metzenbaum scissors, curved</td>
			<td>Aesculap</td>
			<td>BC023R</td>
		</tr>
		<tr>
			<td>Delicate scissors, curved</td>
			<td>Aesculap</td>
			<td>BC061R</td>
		</tr>
		<tr>
			<td>Artery forceps, curved</td>
			<td>Aesculap</td>
			<td>BH109R</td>
		</tr>
		<tr>
			<td>Artery forceps, curved, 1x2 teeth</td>
			<td>Aesculap</td>
			<td>BH121R</td>
		</tr>
		<tr>
			<td>Probe, double-ended</td>
			<td>Aesculap</td>
			<td>BN113R</td>
		</tr>
		<tr>
			<td>Micro needle holder</td>
			<td>Aesculap</td>
			<td>FM 541R</td>
		</tr>
		<tr>
			<td>Micro forceps</td>
			<td>Aesculap</td>
			<td>FM571R</td>
		</tr>
		<tr>
			<td>Micro scissors</td>
			<td>Aesculap</td>
			<td>FM470R</td>
		</tr>
		<tr>
			<td>Disposable eye cautery</td>
			<td>John Weiss International</td>
			<td>0111122</td>
		</tr>
		<tr>
			<td>Cotton buds</td>
			<td>Hartmann AG</td>
			<td>9679369</td>
		</tr>
	</tbody>
</table>
Table 3. Surgical equipment.

roux-en-y gastric bypass operation in rats

Currently, the most effective therapy for the treatment of morbid obesity to induce significant and maintained body weight loss with a proven mortality benefit is bariatric surgery1,2. Consequently, there has been a steady rise in the number of bariatric operations done worldwide in recent years with the Roux-en-Y gastric bypass (gastric bypass) being the most commonly performed operation3. Against this background, it is important to understand the physiological mechanisms by which gastric bypass induces and maintains body weight loss. These mechanisms are yet not fully understood, but may include reduced hunger and increased satiation4,5, increased energy expenditure6,7, altered preference for food high in fat and sugar8,9, altered salt and water handling of the kidney10 as well as alterations in gut microbiota11. Such changes seen after gastric bypass may at least partly stem from how the surgery alters the hormonal milieu because gastric bypass increases the postprandial release of peptide-YY (PYY) and glucagon-like-peptide-1 (GLP-1), hormones that are released by the gut in the presence of nutrients and that reduce eating12.
During the last two decades numerous studies using rats have been carried out to further investigate physiological changes after gastric bypass. The gastric bypass rat model has proven to be a valuable experimental tool not least as it closely mimics the time profile and magnitude of human weight loss, but also allows researchers to control and manipulate critical anatomic and physiologic factors including the use of appropriate controls. Consequently, there is a wide array of rat gastric bypass models available in the literature reviewed elsewhere in more detail 13-15. The description of the exact surgical technique of these models varies widely and differs e.g. in terms of pouch size, limb lengths, and the preservation of the vagal nerve. If reported, mortality rates seem to range from 0 to 35%15. Furthermore, surgery has been carried out almost exclusively in male rats of different strains and ages. Pre- and postoperative diets also varied significantly.
Technical and experimental variations in published gastric bypass rat models complicate the comparison and identification of potential physiological mechanisms involved in gastric bypass. There is no clear evidence that any of these models is superior, but there is an emerging need for standardization of the procedure to achieve consistent and comparable data. This article therefore aims to summarize and discuss technical and experimental details of our previously validated and published gastric bypass rat model.

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Roux-en-Y Gastric Bypass Operation in Rats

Numerous studies using gastric bypass rat models have been recently conducted to uncover the underlying physiological mechanisms of Roux-en-Y gastric bypass operations. This article aims to demonstrate and discuss the technical and experimental details of our published gastric bypass rat model to understand advantages and limitations of this experimental tool.

Currently, the most effective therapy for the treatment of morbid obesity to induce significant and maintained body weight loss with a proven mortality ...

roux-en-y-gastric-bypass-operation-in-rats

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23.4K Views.  University Hospital Zürich. Numerous studies using gastric bypass rat models have been recently conducted to uncover the underlying physiological mechanisms of Roux-en-Y gastric bypass operations. This article aims to demonstrate and discuss the technical and experimental details of our published gastric bypass rat model to understand advantages and limitations of this experimental tool.