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>

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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JoVE Journal

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23.4K vistas.  University Hospital Zürich. Numerosos estudios con modelos de ratas de bypass gástrico se han llevado a cabo recientemente para descubrir los mecanismos fisiológicos de Roux-en-Y las operaciones de bypass gástrico. En este artículo se pretende demostrar y discutir los detalles técnicos y experimentales de nuestro modelo de rata de derivación gástrica publicada a entender las ventajas y limitaciones de esta herramienta experimental.

Video: Roux-en-Y Gastric Bypass Operation in Rats

Techniques of Sleeve Gastrectomy and Modified Roux-en-Y Gastric Bypass in Mice

Obesity is a major public health issue, with a prevalence of 4 to 28% for men and 6.2 to 36.5% for women in Europe (from 2003 to 2008). Morbid obesity is frequently associated with metabolic complications, such as type 2 diabetes, hypertension, and dyslipidemia, reducing life expectancy and quality. In the absence of any effective noninvasive treatments, bariatric surgery is a valuable therapeutic option for patients with morbid obesity (body mass index (BMI) &#62;40 kg/m2), leading to long-term, sustained weight loss and improvements in metabolic complications. However, the underlying cellular and molecular mechanisms sustaining the beneficial effects of bariatric surgery are not yet fully understood. Due to the numerous genetically-modified strains available, the mouse model is the most convenient animal model to explore the molecular mechanisms behind the pleiotropic beneficial effects of bariatric surgeries. Here, we detailed the optimized healthcare methods and surgical protocols in mice for the two most widely-used bariatric surgeries: the sleeve gastrectomy and the modified Roux-en-Y gastric bypass. Deciphering the molecular mechanisms underlying the therapeutic effects of bariatric surgeries offers the promise of identifying new therapeutics targets.

Bariatric surgery is the most efficient way to reduce body weight and the deadly metabolic complications (diabetes, obesity, and dyslipidemia) frequently associated with morbid obesity. Mouse models of bariatric surgery represent a unique asset for deciphering molecular mechanisms behind the beneficial effects of these surgeries on diabetes, hypertension, and dyslipidemia.

Obesity is a major public health issue, with a prevalence of 4 to 28% for men and 6.2 to 36.5% for women in Europe (from 2003 to 2008). Morbid obesity is ...

Cardiopulmonary Bypass in a Mouse Model: A Novel Approach

As prolonged cardiopulmonary bypass becomes more essential during cardiac interventions, an increasing clinical demand arises for procedure optimization and for minimizing organ damage resulting from prolonged extracorporal circulation. The goal of this paper was to demonstrate a fully functional and clinically relevant model of cardiopulmonary bypass in a mouse. We report on the device design, perfusion circuit optimization, and microsurgical techniques. This model is an acute model, which is not compatible with survival due to the need for multiple blood drawings. Because of the range of tools available for mice (e.g., markers, knockouts, etc.), this model will facilitate investigation into the molecular mechanisms of organ damage and the effect of cardiopulmonary bypass in relation to other comorbidities.

This paper describes how to perform cardiopulmonary bypass in mice. This novel model will facilitate the investigation of the molecular mechanisms involved in organ damage.

As prolonged cardiopulmonary bypass becomes more essential during cardiac interventions, an increasing clinical demand arises for procedure optimization ...

One-anastomosis Gastric Bypass (OAGB) in Rats

The goal of this protocol is to set up a preclinical model of bariatric surgery and, more specifically, OAGB in obese rats. Based on this preclinical model, longitudinal studies can be carried out to provide an improved understanding of the mechanisms underlying the outcomes seen after bariatric surgery in humans. For this purpose, rats are operated on through a laparotomy under general anesthesia with isoflurane. First, the surgeon creates a long and tubular gastric pouch: after greater curve and hiatal dissection, the nonglandular stomach is stapled and removed. Then, the remaining stomach is also stapled in order to create a gastric tube and exclude the antrum of the stomach. After that, the surgeon performs a single end-to-side gastrojejunostomy 35 cm from the duodenojejunal angle. This limb length has been chosen in order to reproduce the same ratio between the biliopancreatic limb (BPL) and common limb (CL) length as in human bariatric surgery. The operation ends by aponeurotic and cutaneous closure. The early postoperative management consists of subcutaneous hydration, an intramuscular prophylactic antibiotic injection, a parietal injection of xylocaine, the administration of painkillers, and a progressive reintroduction of diet.

One-anastomosis Gastric Bypass OAGB in Rats

This protocol is for the performance of one-anastomosis gastric bypass (OAGB) on rat. The operator performs a long and tubular-stapled gastric pouch followed by hand-sewn anastomosis. For this model, the operator reproduces the same ratio between biliopancreatic and common limb in humans; therefore, the biliopancreatic limb measures 35 cm.

The goal of this protocol is to set up a preclinical model of bariatric surgery and, more specifically, OAGB in obese rats. Based on this preclinical ...

A Protocol for Roux-en-Y Gastric Bypass in Rats using Linear Staplers

Roux-en-Y gastric bypass (RYGB) is commonly performed for the treatment of severe obesity and type 2 diabetes. However, the mechanism of weight loss and metabolic changes are not well understood. Multiple factors are thought to play a role, including reduced caloric intake, decreased nutrient absorption, increased satiety, the release of satiety-promoting hormones, shifts in bile acid metabolism, and alterations in the gut microbiota.
The rat RYGB model presents an ideal framework to study these mechanisms. Prior work on mouse models have had high mortality rates, ranging from 17 to 52%, limiting their adoption. Rat models demonstrate more physiologic reserve to surgical stimulus and are technically easier to adopt as they allow for the use of surgical staplers. One challenge with surgical staplers, however, is that they often leave a large gastric pouch which is not representative of RYGB in humans. 
In this protocol, we present a RYGB protocol in rats that result in a small gastric pouch using surgical staplers. Utilizing two stapler fires which remove the forestomach of the rat, we obtain a smaller gastric pouch similar to that following a typical human RYGB. Surgical stapling also results in better hemostasis than sharp division. Additionally, the forestomach of the rat does not contain any glands and its removal should not alter the physiology of RYGB.
Weight loss and metabolic changes in the RYGB cohort were significant compared to the sham cohort, with significantly lower glucose tolerance at 14 weeks. Furthermore, this protocol has an excellent survival of 88.9% after RYGB. The skills described in this protocol can be acquired without previous microsurgical experience. Once mastered, this procedure will provide a reproducible tool for studying the mechanisms and effects of RYGB.

Roux-en-Y gastric bypass (RYGB) is performed to treat obesity and diabetes. However, the mechanisms underlying RYGB's efficacy are not fully understood, and studies are limited by technical difficulty leading to high mortality in animal models. This article provides instructions on how to perform RYGB in rats with high success rates.

Roux-en-Y gastric bypass (RYGB) is commonly performed for the treatment of severe obesity and type 2 diabetes. However, the mechanism of weight loss and ...

Robotic Central Pancreatectomy with Roux-en-Y Pancreaticojejunostomy

Central pancreatectomy is a parenchyma-sparing alternative to distal pancreatectomy in patients with a benign or low-grade malignant tumor in the body of the pancreas. The aim of central pancreatectomy is to prevent postoperative life-long endocrine and exocrine insufficiency. The downside of central pancreatectomy is the high rate of postoperative pancreatic fistula, which is the main reason that many surgeons do not routinely use central pancreatectomy in eligible patients. Most studies report open or laparoscopic central pancreatectomy with a pancreatico-gastrostomy anastomosis in adults. This is the first description of a standardized approach to robotic central pancreatectomy with Roux-en-Y pancreaticojejunostomy reconstruction in an adolescent (16-year-old boy) with a pseudopapillary tumor in the body of the pancreas. The operation time was 248 min with 20 mL of blood loss. The postoperative course was uneventful except for the short-term medical treatment for a grade B pancreatic fistula. Robotic central pancreatectomy can be safely applied in selected patients in experienced centers.

Robotic central pancreatectomy may be used in selected patients in experienced centers. This protocol presents all steps and the feasibility of a robotic central pancreatectomy with Roux-en-Y pancreaticojejunostomy in a 16-year-old adolescent patient.

Central pancreatectomy is a parenchyma-sparing alternative to distal pancreatectomy in patients with a benign or low-grade malignant tumor in the body of ...

Single-Anastomosis Duodeno-Ileal Bypass with Sleeve Gastrectomy Model in Mice

Obesity is a major health issue worldwide. As a response, bariatric surgeries have emerged to treat obesity and its related comorbidities (e.g., diabetes mellitus, dyslipidemia, non-alcoholic steatohepatitis, cardiovascular events, and cancers) through restrictive and malabsorptive mechanisms. Understanding the mechanisms by which these procedures allow such improvements often require their transposition into animals, especially in mice, because of the ease of generating genetically modified animals. Recently, the single-anastomosis duodeno-ileal bypass with sleeve gastrectomy (SADI-S) has emerged as a procedure that uses both restrictive and malabsorptive effects, which is being used as an alternative to gastric bypass in case of major obesity. Thus far, this procedure has been associated with strong metabolic improvements, which has led to a marked increase in its use in daily clinical practice. However, the mechanisms underlying these metabolic effects have been poorly studied as a result of a lack of animal models. In this article, we present a reliable and reproducible model of SADI-S in mice, with a special focus on perioperative management. The description and use of this new rodent model will be helpful for the scientific community to better understand the molecular, metabolic, and structural changes induced by the SADI-S and to better define the surgical indications for clinical practice.

Single-anastomosis duodeno-ileal bypass (SADI-S) is an emerging bariatric procedure with important metabolic effects. In this article, we present a reliable and reproducible model of SADI-S in mice.

Obesity is a major health issue worldwide. As a response, bariatric surgeries have emerged to treat obesity and its related comorbidities (e.g., diabetes ...

Gastric Ultrasound Technique for Mitigating Peri-Procedural Aspiration Risk

Gastric Point of Care Ultrasound in Adults: Image Acquisition and Interpretation

Over the past two decades, diagnostic point-of-care ultrasound (POCUS) has emerged as a rapid and non-invasive bedside tool for addressing clinical inquiries related to gastric content. One emerging concern pertains to patients about to undergo sedation and/or endotracheal intubation: the elevated risk of aspiration from the patient&#39;s stomach contents. Aspiration of gastric contents into the lungs poses a serious and potentially life-threatening complication. This occurs more frequently when the stomach is considered &#34;full&#34; and can be affected by the techniques employed for airway management, making it potentially preventable. To mitigate the risk of peri-procedural aspiration, two distinct medical specialties (anesthesiology and critical care medicine) have independently developed techniques to utilize ultrasonography for identifying patients requiring &#34;full stomach&#34; precautions. Due to these separate specialties, the work of each group remains relatively unfamiliar outside its respective field. This article presents descriptions of both techniques for gastric ultrasound. Furthermore, it explains how these approaches can complement each other when one of them falls short. Regarding image acquisition, the article covers the following topics: indications and contraindications, selection of the appropriate probe, patient positioning, and troubleshooting. The article also delves into image interpretation, complete with example images. Additionally, it demonstrates how one of the two techniques can be employed to estimate gastric fluid volume. Lastly, the article briefly discusses medical decision-making based on the findings of this examination.

Author Spotlight: Point-of-Care Ultrasound for Gastric Content Assessment and Risk Stratification in Perioperative Care 

This protocol introduces two methods for image acquisition in gastric ultrasonography. Additionally, tips are provided for interpreting this information to assist in medical decision-making.

Over the past two decades, diagnostic point-of-care ultrasound (POCUS) has emerged as a rapid and non-invasive bedside tool for addressing clinical ...

Exploring Left Upper Quadrant Gastric Body Views for Advanced Gastric Ultrasound Evaluations

&lt;i&gt;Desmodium caudatum &lt;/i&gt; Decoction&#039;s Impact on Intestinal Microbiota of Rats

Effects of Desmodium caudatum on Gastrointestinal Hormones and Intestinal Flora in Rats with Gastritis

In order to preliminarily explore the effects of Desmodium caudatum on gastritis and intestinal flora in rats, a chronic gastritis rat model was established using the classic sodium salicylate method. Eighteen SPF rats were divided into three groups: the control group (Group C), the model group (Group M), and the treatment group (Group T). Pathological sections of the gastric wall were taken from rats in each group. Furthermore, the concentrations of gastrin and malondialdehyde in the serum of rats in each group were determined by ELISA. Additionally, the effects of D. caudatum on the intestinal flora of rats with gastritis were explored through a detailed comparison of gut bacterial communities in the three groups, employing Illumina-based 16S rRNA gene sequencing. The results indicated that D. caudatum decoction could reduce the malondialdehyde content and increase the gastrin content. Moreover, D. caudatum decoction was found to enhance the diversity and abundance of intestinal flora, exerting a positive impact on the treatment of gastritis by regulating and restoring the intestinal flora.

Author Spotlight: Exploring the Mysteries of Sichuan&#039;s Herbal Medicine in Chinese Medicine Research

The present protocol describes the method for analyzing intestinal flora using Illumina-based 16S rRNA gene sequencing and provides a framework for evaluating the effectiveness of herbal decoctions.

In order to preliminarily explore the effects of Desmodium caudatum on gastritis and intestinal flora in rats, a chronic gastritis rat model was ...

Osteoporosis Management in Rats Through Lingnan Fire-Needle Therapy

Operation Procedure and Precautions of Lingnan Fire-Needle Therapy in Osteoporosis Model Rats

Compared to filiform needle therapy, fire-needle therapy has both the stimulation of needles and the warming effect of heat, making it have unexpected effects on some chronic diseases and incurable diseases. Osteoporosis (OP) has a high incidence in postmenopausal women and middle-aged and elderly men, and the treatment cycle is long. According to Traditional Chinese Medicine (TCM), Lingnan fire-needle therapy has shown potential in treating osteoporosis. However, there is still a long way to go before it can be widely used. This article focuses on the application of Lingnan fire-needle therapy in the intervention of OP in rats. It covers the selection of needle tools, acupuncture point selection, positioning of rats' bodies, and fixation methods. We also outline the steps and precautions to be taken during and after needling with fire needles. The experiment was done with three groups: a normal group, a model group, and a fire-needle group, each containing 10 rats. The rats in the fire-needle group were treated with fire-needle intervention for six sessions. After the intervention period, we collected femoral specimens and performed micro-CT scans. The results suggest that fire needling can enhance bone morphology and mineral density in OP rats. This information can serve as a methodological basis for conducting basic research on fire-needle therapy.

Author Spotlight: Exploring the Impact of Lingnan Fire-Needle Therapy in Osteoporosis Intervention

Here, we present a protocol for the application of Lingnan Fire-Needle therapy in the intervention of osteoporosis model rats.

Compared to filiform needle therapy, fire-needle therapy has both the stimulation of needles and the warming effect of heat, making it have unexpected ...