Somatotropin is the growth hormone as far as I know. Glucagon controls the glucose in the blood/sugar receptor from the pancreas. It is also used for allergy and other types of reaction from low blood sugar. read more
Glucagon increase liver Glucogenolysis, ketogenesis, ureagenesis, lypolisys. In order to do that it needs to get into the liver, for the glucagon to do that it needs insulin to get into the liver, this is why glucagon needs to increase Insulin secretion. read more