PET OBESITY - PART 9
Pfizer Animal Health, the division of the Pfizer Pharmaceutical Company, recently launched SLENTROL, an exciting new weightloss medication for dogs. After years of research and extensive testing in the US and Europe, final approval as a prescription medication was received from the FDA. It is formulated in an easily administered, once-a-day liquid that can be given directly by mouth or on a treat. Through surveys and other independent studies, Pfizer estimates that as many as four million American dogs are obese and potential candidates for this therapy. Pfizer is quick to point out that this is not a passport to abandon exercise or diets, but rather an important aid for owners who have a hard time cutting back on doggy treats. Slentrol is in a class of its own in the way that it works to reduce the appetite, hence the constant begging that results in our overindulgence with treats. Unlike human weight-loss drugs that prevent fat absorption by the intestinal lining cells, (for example - Alli) resulting with certain undesirable side effects such as oily discharges, cramping and excess gas, Slentrol works in the small intestines of the dogs and through the release of certain hormones, stimulates the appetite center of the brain to feel full or satisfied. Without getting too scientific, I'll spend the remainder of this article on how this works.
As the dog consumes his meal, the fat (triglyceride) must be broken down into individual fatty acids and monoglycerides by a pancreatic enzyme (lipase) that is released into the small intestine, before the fat can be absorbed by the body. This absorption occurs in the cells lining the inside of the intestinal wall, known as enterocytes. Once inside the enterocyte, these digested fats are then "repackaged" with proteins to a form compounds (chylomicrons) that are then absorbed into the bloodstream and utilized by the body. When an excess amount of fat is absorbed, these chylomicrons are laid down as fat depots. (Refer to Pet Obesity - Part III) With Slentrol, this "repackaging" into chylomicrons is inhibited once inside the enterocyte, thereby preventing the absorption of the consumed fat by the body. As a result, these digested fats accumulate within the enterocytes, triggering the release of certain hormones (PYY) that enter the circulation, reach the hypothalamus (the appetite center of the brain) and acts as a satiety signal. This results in a decreased appetite to a level that is necessary to support a normal body weight for the dog. This negative feedback hormone system is responsible for 90% of the weight loss that is achieved with Slentrol. The other 10% is a result of the fat contained within the enterocytes leaving the body through the feces, as these cells are normally sloughed off every few days. Because there is no "free fat" in the feces, the consistency or volume of the stool is unchanged.