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  Ivermectin Toxicity in Collies


For many years, veterinarians knew a certain pharmaceutical used to eliminate internal parasites in animals was very toxic to a subpopulation of collies. What they didnít know was why.

A test is now available for drug sensitivity.

Examining the eyes of a collie dog
  Now a pharmacologist at the WSU College of Veterinary Medicine has discovered a mutant gene for a key transport protein in the susceptible collies. The gene codes for P-glycoprotein, a large protein complex that acts to pump medications out of the brain and back to the bloodstream where they can be metabolized safely. In the collies that lacked the complete gene for P-glycoprotein, they do not produce the complete protein and cannot pump out the medications. The drugs then build within the brain to toxic levels. P-glycoprotein also helps transport other drugs out of the brain and other tissues in humans and animals, including popular over-the-counter medications.

Discovery of the mutant P-glycoprotein gene may be a key step in screening individuals for certain drug susceptibilities or even pharmaceutical re-design of popular medications to make them safer for all species.

Contact Katrina Mealey at 509/335-2988,

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