Endocrine System

Along with the nervous system , the endocrine system coordinates all of our body’s functions. The hypothalamus, a group of nerve cells located at the base of the brain, integrates these two systems.

Glands of the Endocrine System

Endocrine glandsare located in different parts of the body:pituitary,thyroid andparathyroid, thymus,adrenal glands,pancreasand thesex glands.

Pituitary gland

Thepituitary glandis located in the center of the head, just below the brain. It produces several hormones, including growth hormone.

It is considered themaster gland of our body,as it stimulates the functioning of other glands, such as the thyroid and sexual glands.

Excess production of this hormone causesgigantism(excessive growth) and a lack causesdwarfism.

Another hormone produced by the pituitary gland is theantidiuretic(ADH), a substance that allows the body to save water during excretion (urine formation).

Thyroid

The thyroid is located in the neck and producesthyroxine, a hormone that controls the speed of cellular metabolism, maintaining weight and body heat, growth and heart rate.

Hyperthyroidism, an overactive thyroid, speeds up the entire metabolism: the heart beats faster, the body temperature is higher than normal, and the person loses weight by using more energy.

This condition favors the onset of heart and vascular diseases, as the blood circulates with more pressure. If left untreated, it can cause the appearance ofgoiter(swelling in the neck) and alsoexophthalmos(bulging eyes).

Hypothyroidism is when the thyroid gland works less and produces less thyroxine. As a result, the metabolism slows down, some areas of the body become swollen, the heart beats more slowly, blood circulates more slowly, the person uses less energy, tends to gain weight and physical and mental responses become slower and, if left untreated, goiter can occur.

Parathyroids

The parathyroids are four small glands, located behind the thyroid, that produceparathyroid hormone, a hormone that regulates the amount of calcium and phosphorus in the blood.

The decrease in this hormone reduces the amount of calcium in the blood and causes the muscles to contract violently.

This symptom is calledtetany, as it is similar to what occurs in people with tetanus. In turn, the increased production of this hormone transfers part of the calcium to the blood, weakening the bones and making them brittle.

Timo

Thethymus gland is located between the lungs. It produces a hormone that acts to defend the newborn’s body against infections.

At this stage, it presents a marked volume, growing normally until adolescence, when it begins to atrophy. In adulthood, it decreases in size, as its functions are reduced.

Adrenals

The adrenal glands are located above the kidneys and produceadrenaline, a hormone that prepares the body for action. The effects of adrenaline on the body are:

• Tachycardia: the heart races and pumps more blood to the legs and arms, increasing the ability to run or get excited in tense situations;
• Increased respiratory rate and blood glucose levels, releasing more energy for cells;
• Contraction of the blood vessels in the skin, so that the body sends more blood to the skeletal muscles and, as a result, we become “pale with fright” and also “cold with fear”.

Pancreas

The pancreas is amixed glandbecause in addition to hormones (insulin and glucagon), it also produces pancreatic juice, which is released into the small intestine and plays an important role in digestion.

Insulin controls the entry of glucose into cells (where it will be used to release energy) and storage in theliver, in the form of glycogen.

Lack of or low production of insulin causesdiabetes, a disease characterized by excess glucose in the blood (hyperglycemia).

Glucagon works in the opposite way to insulin. When the body goesmanyhours without eating, blood sugar levels drop significantly and the person may experience hypoglycemia , which causes a feeling of weakness, dizziness, and in many cases, even fainting.

In this case, the pancreas produces glucagon, which acts on the liver, stimulating the “breakdown” of glycogen into glucose molecules. Finally, the glucose is sent to the blood, normalizing hypoglycemia.

Sex glands

The sexual glands are theovariesandtesticles, which are part of thefemale reproductive systemand the male reproductive system respectively.

The ovaries and testicles are stimulated by hormones produced by thepituitary gland. Thus, while the ovaries produceestrogenandprogesterone, the testicles produce several hormones, includingtestosterone, which is responsible for the appearance of male secondary sexual characteristics: beard, deep voice, broad shoulders, etc.