Peptidhormoon

Peptidhormoon refers to peptide hormones, which are a class of signaling molecules derived from amino acids. These hormones are produced by endocrine glands in the body and play crucial roles in regulating a wide range of physiological processes. Unlike steroid hormones, which are lipid-soluble, peptide hormones are water-soluble and bind to receptors on the surface of target cells.

The synthesis of peptide hormones begins with the transcription of genes into messenger RNA (mRNA), which is then translated into precursor proteins. These precursor proteins undergo further processing, including cleavage and folding, to form the mature peptide hormone. They are then stored in secretory vesicles within endocrine cells before being released into the bloodstream in response to specific stimuli.

Once in circulation, peptide hormones travel to their target cells, where they bind to specific receptors. This binding triggers a cascade of intracellular events, often involving second messengers like cyclic AMP (cAMP) or calcium ions. These signaling pathways ultimately lead to a change in cellular activity, such as altered gene expression, enzyme activation, or ion channel modulation.

Examples of peptide hormones include insulin, which regulates blood glucose levels; growth hormone, which promotes growth and cell reproduction; and oxytocin, involved in social bonding and childbirth. The diverse functions of peptide hormones highlight their importance in maintaining homeostasis and coordinating bodily functions. Their signaling pathways are often complex and finely tuned, ensuring precise control over physiological responses.