The biggest difference – steroid and peptide hormones
The main difference between steroid hormones and peptide hormones is that steroid hormones bind to cytoplasmic receptors to act as other transcriptional modifiers whereas peptide hormones mainly bind to cytoplasmic cell surface receptors in core DNA.
Steroid and peptide hormones are two types of hormones in the animal body. In general, hormones are a type of signaling molecule produced by the endocrine glands and carried throughout the body by the circulatory system. In addition, hormones regulate the physiology and behavior of distant organs. Additionally, cholesterol produces steroid hormones while amino acids produce peptide hormones. Testosterone and estrogen are examples of steroid hormones, and antidiuretic hormone (ADH) and calcitonin are examples of peptide hormones.
What are steroid hormones?
Steroid hormones are secretions from ductless glands, which consist of a characteristic steroid ring structure. In addition, they are formed by cholesterol. Genital hormones produced in the abdomen (testosterone, estrogen, and progesterone) and hormones produced in the adrenal glands (aldosterone, cortisol, and androgens) are examples of steroid hormones.
If necessary, steroid hormones are also synthesized in the smooth endoplasmic reticulum. Since steroid hormones are small hydrophobic molecules, they can diffuse freely across the lipid bilayer of the plasma membrane. Moreover, they bind to a specific receptor in the cytoplasm and this receptor-bound steroid hormone complex is transported to the nucleus. This receptor-bound steroid hormone complex then binds to specific regions of chromatin. This binding then activates or releases associated chromatin proteins to modify transcription. Ultimately, the steroid hormone determines the amount of a particular protein in a cell. Therefore, the receptor-bound steroid hormone complex acts as a transcriptional regulator. Figure 1 shows the mechanism of action of the steroid hormone.
Anabolic steroid hormones are also synthetic steroids related to male sex hormones. They stimulate protein synthesis in the body to increase muscle mass.
What are peptide hormones?
Peptide hormones refer to all hormones derived from amino acids. These can be small or large hydrophilic molecules that are synthesized in the coarse endoplasmic reticulum. The vesicles retain peptide hormones until they receive signals for secretion. Because they are hydrophilic molecules, peptide hormones cannot freely diffuse across the lipid bilayer. Therefore, peptide hormone receptors are present on the surface of the target cell. Moreover, these receptors are formed by a single polypeptide chain that contains domains on both sides of the plasma membrane. Moreover, these intracellular and extracellular domains are connected by a membrane-spanning domain.
Additionally, some of the receptors produce different polypeptides. Peptide hormones are the first messengers of the signaling pathway. Binding of the peptide hormone to the receptor activates the G protein, which is found in the membrane. Additionally, activated G protein stimulates enzymes such as adenylyl cyclase and phospholipase C in the plasma membrane, creating other messengers such as cyclic AMP (cAMP). These other messengers then bind to protein kinase A. Finally, activated protein kinase A phosphorylates other proteins, triggering a cascade of signals to alter various cellular functions.
Similarities Between Steroid and Peptide Hormones
Steroid and peptide hormones are signaling molecules that regulate the physiology and behavior of organs.
Moreover, both hormones are produced in the endocrine glands and released into the bloodstream to be transported to the target organ.
Both usually work for a long time.
The difference between steroid and peptide hormones
Steroid hormones: Steroid hormones refer to the secretions of ductless glands, which consist of a characteristic steroid ring structure and consist of cholesterol.