What Are Tropic Hormones?

Are you wondering what tropic hormones are? This article will provide a nice overview of what tropic hormones are, what they do, and the different types. 

In short, tropic hormones are hormones that target different glands that secrete hormones. In this way, they play an important role in hormone regulation and are vital for different bodily functions. 

If you want to learn more about tropic hormones, keep on reading. This article explains all the basic information about tropic hormones and their function and gives an overview of  the glands that secrete hormones in the first place. 

Understanding tropic hormones

To understand what tropic hormones are, it is important to define hormones in general. Hormones are chemical messengers in our body that get transported via the bloodstream. They are involved in many bodily functions, such as digestion and sleep. Hormones can also regulate psychological states, such as moods. Hormones are released by glands in our body, referred to as endocrine glands. These glands are in different areas of our body. These areas include:^1,2 

The brain: There are different glands in the brain that secrete hormones. These include: 

• Hypothalamus
• Pineal Gland 
• Pituitary gland

Thyroid gland and Parathyroid gland: Both glands are located in our throat and secrete thyroid hormones, such as T3 and T4. These are involved in the temperature regulation of the body. 

Adrenal gland and Pancreas: These are located in our tummy and secrete steroid hormones such as adrenaline. Those hormones are involved in all kinds of bodily functions, such as blood pressure.

Ovaries and Testes: In men, the testes are located in the crotch, whereas in women, the ovaries are inside the lower tummy. Both glands secrete sex hormones, such as testosterone and oestrogen. 

While there are many glands that are vital for hormonal secretion and balance, hormones can also be secreted by other tissues in the body. These tissues include: 

Fat Tissue: which gives the body information about the amount of fat the body has. Fat tissue also secretes  other hormones, such as oestrogen. 

Liver: The liver is involved in glucose metabolism by secreting insulin. 

Kidneys: are related to urination and the related hormones. 

Placenta: The placenta secretes hormones, among other times, during pregnancy. The secreted hormones include: human placental lactogen and oestrogen. 

Gastrointestinal  tract: The GI-Tract also releases different hormones , mainly linked to digestion and eating behaviour . The stomach secretes ghrelin, which signals that the stomach is empty. So, when ghrelin is secreted by the stomach, you start feeling hungry. 

Thus, hormones have different effects on our body and are secreted by different glands and tissues in the body. Tropic hormones target the glands that secrete hormones. In this way, they control the secretion of certain hormones of these glands by either inhibiting or stimulating the gland. 

Tropic hormones types and functions

As mentioned, tropic hormones are involved in the regulation of glands that secrete hormones, and in this way, are essential  for the hormonal regulation in the body. 

The different tropic hormones and their function are listed below:²  

Corticotropin-releasing  Hormone (ACTH) is also referred to as Adrenocorticotropic hormone. ACTH stimulates the adrenal gland to release cortisol. Cortisol is released by the adrenal gland. It is relevant for many bodily functions, such as the regulation of the immune system.³ 

Gonadotropin Releasing  Hormone (GnRH) is involved in reproduction by upregulating the secretion of two other tropic hormones:⁴ 

• Follicle stimulating hormone (FSH): In women, FSH is involved in the regulation of the menstrual cycle. In men, FSH is involved in the regulation of sperm production. FSH stimulates the production of oestrogen from the ovaries⁵  
• Luteinising Hormone (LH): In women, LH is involved in the menstrual cycle. In men, LH stimulates the release of testosterone⁶ 

Growth Hormone-releasing Hormone (GHRH): As the name says, GHRH stimulates the release of the growth hormone which is involved in growth and cell reproduction.⁷ 

Thyrotropin-releasing Hormone (TRH): This hormone stimulates the release of the thyroid-releasing  hormone and prolactin.⁷  

• Thyroid-stimulating Hormone (TSH): TSH stimulates the release of thyroid hormones
• Prolactin (PRL): Prolactin stimulates milk production in female breasts after pregnancy. It is stimulated by TRH and Prolactin-releasing Factor (PRF). 

Melanocyte stimulating hormone (MSH): MSH stimulates the secretion of 

There are many different tropic hormones, which can seem overwhelming. To make it less overwhelming, it can help to look at the meaning of the name. Oftentimes, what the tropic hormones do is already in the name. For instance, the thyroid stimulating hormone stimulates thyroid hormones. 

Summary

Tropic hormones are vital for hormonal regulation in the body and are secreted by different glands. Tropic hormones stimulate and act on different glands that secrete hormones, such as the adrenal gland, and in this way regulate the release of different hormones in our bodies. Tropic hormones include: Corticotropin-releasing  Hormone (ACTH), Gonadotropin-releasing  Hormone (GnRH), Follicle stimulating hormone (FSH), Luteinising Hormone (LH), Growth Hormone-releasing Hormone (GHRH), Thyrotropin-releasing Hormone (TRH), Thyroid-stimulating Hormone (TSH).