Leptin is a protein hormone produced by adipose tissue.

This is true of protein hormones generally.

In fact the molecules of most protein hormones are so small, for proteins, that the very name is sometimes denied them.

The hormone obtained from cattle is rather large for a protein hormone and has a molecular weight of 45,000.

Sometimes, athletes try to mask their injury pain with drugs, including narcotics, protein hormones and local anesthetics.

Relaxin is a protein hormone first described in 1926 by Frederick Hisaw.

Examples of protein hormones include insulin and growth hormone.

This is a protein hormone, secreted by the intestine.

There are three naturally occurring protein hormones in the body that cause natriuresis.

Insulin is a protein hormone that contains 51 amino acids.