[Biology Class Notes] on Pineal Gland Pdf for Exam

Pineal Gland Location

A small gland in the brain is called the pineal gland. The functions of this pinecone–shaped gland are yet to be fully understood. Researchers know that it produces and regulates some hormones, including melatonin. Melatonin is known for its role in regulating sleep patterns. The scientific name for sleep patterns is Circadian rhythms. The pineal gland is a small endocrine gland (secreting hormone directly into the blood). It is found in the back part of the third cerebral ventricle of the brain, which is a fluid-filled space in the brain. In this article, we will focus on the pineal gland function.

The other name for pineal gland is a pineal body. It is a small endocrine gland that lies in–between the two halves of the brain. It is essential to note that this gland is often larger before puberty or adolescence (teens). In adults, it is approximately 5 to 9 mm and 0.1 grams in weight. As said earlier, it is larger before puberty. The name of this gland is derived from Latin pinea for pine cone. 

Pineal Gland Function 

The pineal gland has a vital role to play in the regulation of female hormone levels. Also, it may affect the fertility and menstrual cycle in women. This reason is attributed in part to the melatonin produced and secreted by the pineal gland. Studies suggest that melatonin may also help protect against cardiovascular issues such as atherosclerosis and hypertension. More research can need to be done into more potential functions of melatonin.

The pineal gland is composed of neuroglial cells, portions of neurons, and cells known as pinealocytes. As mentioned earlier, pinealocytes create and secrete melatonin, a hormone that helps maintain the body’s internal clock. Pinealocytes are endocrine cells. Let us discuss the functions of the pineal gland concerning the following:

1 – Secretion of Hormone Melatonin  

The pineal gland secretes melatonin which is a hormone derived from tryptophan that plays a central role in the regulation of circadian rhythm of the body. This circadian rhythm is the roughly 24-hour cycle of biological activities associated with natural periods of light and darkness. Melatonin sees a large amount of production when it is dark. Light inhibits the secretion of melatonin.

2 – Cardiovascular Issues

Melatonin secretion creates a positive effect on the heart and blood pressure. It may also be in use for the treatment of cardiovascular or heart-related diseases.

3 – Reproductive, and Female Hormones

Melatonin holds back the secretion of reproductive hormones from the anterior pituitary gland that secretes hormones into the bloodstream, particularly adrenaline. Reduced amounts of melatonin may play a role leading to irregular menstrual cycles.  ( Ref Fig.1 a)

4 – Mood Stabilization

The size of the pineal gland may indicate a risk for certain mood disorders. Studies suggest that a lower pineal gland volume may increase the risk of developing schizophrenia and other mood disorders. More research on the subject can help to understand better the effect of pineal gland volume.

5 – Reduced Cancer Risk

According to research suggestions, there may be a connection between impaired pineal gland function and cancer risk. Experiments of rats found evidence that lowering of pineal gland function by overexposure to light led to cellular damage and increased the risk of colon cancer. When used with additional treatments, melatonin may improve the outlook for people that have the disease. It may be true in people with advanced tumours.  

Symptoms of Malfunctions in the Pineal Gland 

If there is any impairment in the working of the pineal gland, it can lead to hormonal imbalance. Now, this condition can affect the functioning of other body systems. For instance, a disturbance if sleep patterns. It can also show up disorders such as jet lag and insomnia. As melatonin interacts with female hormones, it can complicate the menstrual cycle and fertility.

The location of the pineal gland is in the vicinity of other vital structures. It interacts heavily with blood and other fluids. If there is a development of pineal gland tumour, it may affect many other things. Early symptoms of a tumour include:

1 – Seizures

2 – Disruptions in memory

3 – Nausea

4 – Headaches

5 – Damage in vision and other senses.

Consult with your doctor if you have any sleep disorder, or if you want to know in detail about taking melatonin supplements.