Which hormone is known for opposing the effects of insulin?

The hormone glucagon is known for its role in opposing the effects of insulin. While insulin works to lower blood sugar levels by facilitating the uptake of glucose into cells, glucagon has the opposite effect; it raises blood sugar levels by stimulating the liver to release glucose into the bloodstream. This balance between insulin and glucagon is crucial for maintaining homeostasis in blood glucose levels.

When blood sugar levels drop, glucagon is released from the alpha cells of the pancreas. It acts on the liver to convert stored glycogen into glucose, which is then released into the bloodstream, effectively increasing blood sugar levels. This response is essential, especially during fasting or when the body requires additional energy.

Understanding the relationship between glucagon and insulin helps clarify how the body regulates glucose metabolism. Glucagon's primary function as a counter-regulatory hormone to insulin is vital for avoiding hypo- or hyperglycemia, demonstrating the delicate balance the endocrine system maintains to support metabolic processes.