Scientists have identified 2 protein receptors in a guinea pig - P2Y1 and P2Y11 - that relax the gut and thus allow it to accommodate a bigger meal. these receptors are also present in humans and may serve as targets for developing drugs to aid in weight management and preventing obesity.

Dr Brian King of the UCL Department of Neuroscience, Physiology and Pharmacology says: "The mechanisms we have identified are important to the normal workings of the stomach - a hollow organ which actively relaxes to help accommodate the size of your meal. The human stomach has a 'resting' internal volume of 75 millilitres but, by relaxing its muscular wall, can expand to an internal volume of two litres or more - a 25-fold increase in the volume it can accept. This expansion is controlled by nerves inside the stomach wall and these nerves release molecules that stimulate the P2Y1 and P2Y11 receptor proteins embedded in muscle cells in the gut wall.

Blocking these receptors may prevent the relaxation of the stomach, and may thus help in regulating an individual's food intake, possibly in a similar mechanism as a lapband surgery would.

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