What type of hormone is glucagon considered based on its action in the liver?

Glucagon is classified as a catabolic hormone because it primarily functions to promote the breakdown of stored energy reserves in the body, specifically within the liver. Its main role is to increase blood glucose levels by stimulating the process of glycogenolysis, where glycogen stored in the liver is converted into glucose and released into the bloodstream. This action is crucial during fasting or between meals when blood sugar levels need to be maintained.

Additionally, glucagon can also encourage gluconeogenesis, the synthesis of glucose from non-carbohydrate sources. Both of these processes underscore its catabolic nature, as they involve the breakdown of stored energy to mobilize glucose.

In contrast, anabolic hormones generally promote synthesis and storage processes, building up tissues and reserves. Therefore, glucagon, with its focus on energy mobilization, aligns clearly with catabolic activities.