What is the target tissue for epinephrine?
Major Hormones: Origin, Target, Function
| HORMONE | GLAND ORIGIN | TARGET TISSUE |
|---|---|---|
| Epinephrine | Adrenal gland | Muscles and blood vessels |
| Norepinephrine | Adrenal gland | Muscles and blood vessels |
| Glucagon | Pancreas | Liver |
| Insulin | Pancreas | Throughout body |
What effect does epinephrine have on target cells?
Epinephrine will bind to the receptor on the outside of a liver cell allowing a conformational change to occur. This receptor shape change allows G protein to bind, and become active. The activation G protein causes a conformational change on the molecule causing adenylate cyclase to bind.
What is the target tissue for this hormone?
| Endocrine gland/ source of hormone | Hormone | Target organ or tissue |
|---|---|---|
| Anterior pituitary (adenohypophysis) | LH (luteinizing hormone) | Ovaries / testes (Leydig cells) |
| GH (growth hormone) | All tissues | |
| TSH (thyroid stimulating hormone) | Thyroid gland | |
| Prolactin | Mammary gland |
What are the target cells of epinephrine and norepinephrine?
Both epinephrine and norepinephrine work on alpha and beta receptors. However, epinephrine has a greater effect on beta receptors compared with norepinephrine. Alpha receptors are only found in the arteries. Beta receptors are in the heart, lungs, and arteries of skeletal muscles.
What is the target organ of somatostatin?
Somatostatin from the hypothalamus inhibits the pituitary gland’s secretion of growth hormone and thyroid stimulating hormone. In addition, somatostatin is produced in the pancreas and inhibits the secretion of other pancreatic hormones such as insulin and glucagon.
What is the function of melanocyte-stimulating hormone?
Melanocyte-stimulating hormone describes a group of hormones produced by the pituitary gland, hypothalamus and skin cells. It is important for protecting the skin from UV rays, development of pigmentation and control of appetite.
What happens when epinephrine is released from the adrenal medulla?
The adrenal medulla releases epinephrine and norepinephrine (NE) into the bloodstream. Circulating epinephrine stimulates breathing, blood pressure, heart rate, and vasoconstriction and widens bronchioles in the lungs. These changes direct more blood to the muscles, heart, and other vital organs.
How does epinephrine cause smooth muscle relaxation?
Epinephrine binds both α and β adrenergic receptors to cause vasoconstriction and vasodilation. When activated, the α1 receptor triggers smooth muscle contraction in blood vessels in the skin, gastrointestinal tract, kidney, and brain, among other areas.
How do hormones affect target tissues?
Hormones cause cellular changes by binding to receptors on target cells. The number of receptors on a target cell can increase or decrease in response to hormone activity. Hormones can affect cells directly through intracellular hormone receptors or indirectly through plasma membrane hormone receptors.
What does T3 and T4 target?
The cells of the developing brain are a major target for T3 and T4. Thyroid hormones play a particularly crucial role in brain maturation during fetal development by regulating actin polymerization during neuronal development.
What are the effects of epinephrine and norepinephrine?
Epinephrine and norepinephrine are similar chemicals that act as both neurotransmitters and hormones in the body. Both substances play an important role in the body’s fight or flight response, and their release into the bloodstream causes increased blood pressure, heart rate, and blood sugar levels.
What is cortisol target tissue?
Cortisol acts on the liver, muscle, adipose tissue, and pancreas.