 Hey everybody, Dr. O'Hare, this is a very important video because I'm going to do a quick overview of all the key hormones in your body. So here you see your endocrine system and we won't go through all the glands here, I'll be covering them all in separate details, but I just wanted this high level view of what is the key function or two of all of the major endocrine hormones. So this is going to be the structures where they come from here, but let's just go to the list. I'll just go right in order here, not in order of importance. So we're going to start with the pituitary hormones, you'll see the pituitary gland is called the master gland for a reason because this is where a lot of the hormones come from. So the first one is growth hormone, well growth hormone like the name implies leads to growth. It does so by increasing protein synthesis, excuse me, the other key thing growth hormone does is increases lepolysis or the breakdown of fat for fuel. So growth hormone is going to lead to a building up of muscle and a loss of fat as you do so. So that's growth hormone. The second one is prolactin. So prolactin is needed for the development of the mammary glands and the production of milk, but very important, not the ejection of milk. So the let down reflex is caused by oxytocin hormone later in this list. So prolactin, just remember development of the mammary glands and production of milk lacked being right there in the name prolactin. Next we have thyroid stimulating hormone, does exactly like the name says, stimulates the thyroid gland to produce its thyroid hormones. What we got next, ACTH is adrenocorticotropic hormone, so terrible name, but it stimulates the adrenal cortex, that's exactly what it's supposed to do. The adrenal cortex is going to have hormones like aldosterone and your stress hormone cortisol and then some of your antigens will be there too. So we'll cover that separately, but the adrenocorticotropic hormone stimulates the adrenal cortex to release its hormones. Next we have the two gonadotropins, follicle stimulating hormone and luteinizing hormone. So they both are important for both men and women, but we think about them with females a lot more. So a simple little rule, F comes before L in the alphabet, E comes before P. So follicle stimulating hormone primarily leads to an increase in estrogen, luteinizing hormone leads to an increase in progesterone, that's just a little hint you can use there. But follicle stimulating hormone is going to lead to gamete production, so it's going to stimulate the follicle, which is where the oocyte, the egg is in females. It's also going to lead to the maturation of sperm in males. Luteinizing hormone is going to stimulate the production of progesterone like we mentioned, but also it will lead to the production of testosterone in males. So primarily. So that is follicle stimulating hormone and luteinizing hormone. Next we have anti diuretic hormone. It says here it's a posterior pituitary hormone. Both of these hormones here, ADH and oxytocin, are secreted from the posterior pituitary gland, but they're actually produced by the hypothalamus. So anti diuretic hormone, like the name implies, is an anti diuretic. It opens these aquapor and water channels in the kidneys, which lead to an increased reabsorption of water, so you're going to produce less urine, that is anti diuretic hormone. Oxytocin, oxytocin is needed for uterine contractions for labor and delivery, to deliver a baby, and then also for the ejection of milk. So it's the, I guess the ejection of milk and then also the ejection of a baby. That's oxytocin. Now we could talk about it being a pair bonding molecule and other things, but this is just an introduction. So oxytocin, think delivery of a baby and the let down reflects milk release, not milk production. Last one here is from the intermediate zone, which is between the anterior and posterior lobes of the pituitary gland. This is melanocyte stimulating hormone. So like its name implies, it stimulates melanocytes. We don't, there are other things that it does too. We don't completely understand this hormone, because most of the skin, the melanin production in your skin would be caused by local melanocyte stimulating hormone. But this is, that's what it does. So melanocyte stimulating hormone stimulates melanocytes to make melanin. Okay. Next we have the thyroid glands. Thyroid glands. So we have thyroid hormones, which would be thyroxine, which is T4 triiodothyrinine, which is T3. The T4 and T3 tell you how many iodines they have. So these are going to be your thyroid hormones. They're going to stimulate your metabolism. The thyroid gland also produces calcitonin. So calcitonin is needed to bring blood calcium levels down. So it's going to put calcium in your bones. It's going to take calcium out of your blood. Calcitonin is a very important hormone when you're younger and you're building bone. Calcitonin levels aren't as high and it's not as significant in adults, which is why old people like me, we lose bone, right? We don't, we don't build it. The goal is to slow bone loss for someone my age. Parathyroid gland produces your parathyroid hormones. It does the opposite. Its job is to keep blood calcium levels up and it'll do so by increasing the absorption of calcium in the gut, increasing the reabsorption of the kidneys, but it also will stimulate your osteoclast, the cells that, that actually break down bone to release blood calcium. So parathyroid hormones job is to keep your blood calcium levels up, whereas calcitonin's job was to keep them down. You'll see that parathyroid hormone is also related to, I signed on the list here, but a hormone called calcitriol, which comes from the kidneys. We'll cover that when we talk about the secondary hormones. Next we have the adrenal cortex. So you see aldosterone is here. Aldosterone is going to increase the reabsorption of sodium at the kidneys and then water is going to follow that sodium in. So aldosterone's job is to, is to keep your plasma volume level up and keep your blood pressure up. So that's what aldosterone does by, by reabsorbing sodium and water following it via osmosis. The adrenal cortex also produces your, what we're called your stress hormones. Cortisol is one we'll talk about the most, but you also have corticosteroin and cortozoam. So their job is to mobilize energy. When you're under stress, your body thinks you should be fighting or flighting, right? The fight, flight or freeze response. So cortisol's job is to bring your blood sugar up and this is why stress hormones break down body tissues. They increase your blood sugar. They do all these kind of negative things. They're not negative in the short term if you are trying to fight or flee, but they are negative long term. So it will cover stress separately too. The adrenal cortex doesn't have it listed here, but this is also, there are androgens produced by the adrenal cortex. So what we call like your, something like your male sex hormones. So, so girls and women and prepubescent boys are getting their androgens from the adrenal glands. Once a boy reaches puberty, the testicles will basically take over. But that is, that is a third, relatively minor function of the adrenal cortex. The cortex is the outside of the adrenal glands, which, which hopefully remember sit on top of the kidneys, the adrenal medulla, the center, the core of the adrenal gland, it's actually part of your sympathetic nervous system. And it's going to lead to the release of epinephrine and norepinephrine. So epinephrine is adrenaline and norepinephrine is noradrenaline. So these are going to be two, two important hormones in the fight, especially in the acute phases, the, the early phases of the fight or flight response system. All right. Next, we have the pineal gland. So the pineal gland is going to receive information from your eyes about whether, whether or not there's light. And if there is light, it will not produce melatonin or not much of it. If there isn't light, it will produce melatonin. So melatonin is important for sleep wake cycles, your circadian rhythms. Melatonin is useful for helping you fall asleep. That's the pineal gland. The pancreas produces more hormones than this, but the only two we care about are insulin and glucagon. So I, so I think about insulin, IN, insulin in your cells. So insulin's job is to bring glucose into your cells, use glucose, store glucose as glycogen. Its goal is to bring your blood sugar levels down. It's a very powerful anabolic hormone, glucagon. If your blood sugar is gone, then you need glucagon to release glycogen stores and mobilize glucose to bring your blood sugar levels back up. So insulin will lower blood sugar levels, glucagon will raise them. Then we have the gonads, testes and males and ovaries and females. The testes produce testosterone and all these different testosterone derivatives, which are needed for what are called your male secondary sexual characteristics, like fat distribution, body hair, voice changes, etc. Then the ovaries are going to produce estrogen and progesterone needed for the development of the eggs and reproduction and the female secondary sexual characteristics. Okay, I know there's a lot there. Hopefully just jot it down some notes quickly. We'll cover, we'll cover all of these in detail where they're needed. But that's a high level overview of all the key endocrine hormones you have to know. It's a long list. This is a very complicated organ system. I hope this helps. Have a wonderful day. Be blessed.