Adrenal Medulla and Pineal Gland (Nursing)

00:00 The second adrenal gland is going to be deep to the adrenal cortex and it's going to be the adrenal medulla. The adrenal medulla contains medullary chromaffin cells, which are going to synthesize our catecholamines such as epinephrine and norepinephrine. The catecholamines are going to be responsible for vasoconstriction; increased heart rate; increased blood glucose levels; and also blood that has diverted to the brain, heart, and skeletal muscles.

00:37 Both hormones have basically the same effect, but epinephrine is more of a stimulator of our metabolic activities. Norepinephrine, on the other hand, is going to have more of an influence on our peripheral vasoconstriction of blood and blood pressure. Responses to stressors by the adrenal medulla are usually brief unlike what we see with the adrenocortical hormones. The next gland that we're going to discuss is the pineal gland. The pineal gland is a small gland that's going to hang from the roof of the 3rd ventricle. It contains pinealocytes, which are going to secrete the hormone melatonin which is derived from serotonin. The location of the pineal gland in the brain is pictured here. The effects of melatonin, the hormone released by the pineal gland, include the timing of sexual maturation and puberty; our day/night cycles also referred to as our circadian rhythm; the physiological processes that show rhythmic variations such as our body temperature, our sleep, and our appetite and as well the production of anti-oxidants and detoxification molecules in cells.