What role do some nonsteroid hormones play?

Some nonsteroid hormones, particularly peptide and protein hormones, play crucial roles in cellular signaling and regulation within the body. These hormones are made up of chains of amino acids and can vary in size. Unlike steroid hormones, which are lipid-soluble and can cross cell membranes to directly influence gene expression, nonsteroid hormones bind to specific receptors on the surface of target cells. This binding activates signaling pathways that trigger a variety of physiological responses.

For example, insulin is a well-known nonsteroid hormone that regulates blood sugar levels by facilitating the uptake of glucose into cells. By interacting with cell surface receptors, nonsteroid hormones can initiate rapid responses, such as altering enzyme activity or affecting ion channel permeability, which affects processes like metabolism, growth, and development.

The roles of various types of hormones are distinct, and it’s important to differentiate these functions. Nonsteroid hormones do not generally act as enzymes for digestion, transmit nerve impulses in the way neurotransmitters do, or form structural proteins. Each type of hormone (steroid and nonsteroid) has its unique mechanisms and effects within the body, highlighting the specificity of hormonal action in physiological processes.