PYY %28Peptide YY%29
Here's your citation in American Psychological Association (APA) format:
PYY %28Peptide YY%29. (n.d.). In Alleydog.com's online glossary. Retrieved from: https://www.alleydog.com/glossary/definition-cit.php?term=PYY+%2528Peptide+YY%2529