Angiotonin is a term used to describe a natural hormone that is responsible for regulating blood pressure by narrowing or widening blood vessels. While angiotonin is the most commonly used name for this hormone, it is also known by a number of other names within the scientific community. Some of the synonyms for angiotonin include angiotensin, renin angiotensin system (RAS), and angiotensin II. Additionally, there are various forms of angiotonin that are produced within the body, such as angiotensin I and angiotensin III. These alternative names for angiotonin are often used interchangeably depending on the context and focus of a particular study or medical case.