What to know about prostaglandins

 Prostaglandins are hormone-like substances. Different tissues in the body can release prostaglandins, including the skin, stomach, and lungs. Having an appropriate amount of this substance is essential to regulating many bodily functions.

There are different types of prostaglandins, and each has a specific function. For example, some prostaglandins can cause inflammation, while others suppress it. Similarly, some prostaglandins promote blood clotting, while others promote bleeding.

Although prostaglandins are essential for many bodily functions, they can also cause issues. Too much inflammation can damage tissues and organs, while excessive blood clotting can lead to severe health problems such as stroke or heart attack. Additionally, prostaglandins may contribute to debilitating pain that can interfere with a person’s daily activities.

Read on to learn more about prostaglandins, what they are, and how they can affect the body.

What are they?

Prostaglandins are hormone-like substances that the body produces in response to injury or illness. They are part of the inflammatory response, which is the body’s natural mechanism for healing.

Prostaglandins consist of fatty acids and are present in all tissues of the body, including the skin, stomach, and lungs.

There are several types of prostaglandin, including:

• prostaglandin D2
• prostaglandin E2
• prostaglandin F2
• thromboxane
• prostacyclin

• Function

  Prostaglandins have hormone-like effects in the body, but, unlike hormones, a specific gland does not release them. Rather, the body has numerous tissues that can make prostaglandins.

  Prostaglandins only perform actions in the local area where the body produces them. This is essential to help regulate and limit the effect they can have on the body.

  Prostaglandins have different functions — and possibly opposite effects — in different tissues. Generally, they may play a role in:

  • constricting or dilating blood vessels, or airways
  • forming blood clots or breaking them apart
  • contracting or relaxing the smooth muscle in the digestive tract
  • contracting the uterus during pregnancy and while not pregnant

  The type of receptor, to which the prostaglandin binds, determines whether it will inhibit or stimulate some of these processes.

  What effect do they have on the body?

  Although prostaglandins may have some significant effects, they are typically shortlived and can only affect nearby cells. For this reason, they are present throughout the body.

  Typically, prostaglandins are involved in the followingTrusted Source:

  Effects on reducing pain

  • Pain and inflammation: Prostaglandins can both cause and ease pain. There are typically high concentrations of prostaglandins in inflamed tissues, and prostaglandin E2 causes redness, swelling, and pain. Experts also know prostaglandins have inflammatory effects, including widening blood vessels, fever promotion, and allergic reactions.
  • Promoting healing: Prostaglandins may help tissues heal, particularly in the digestive tract. They decrease stomach acid production and help the gut release more protective mucus. They also affect blood clotting to prevent bleeding and dissolve blood clots once healing has occurred.
  • Relieving pressure in the eye: An optometrist may prescribe prostaglandin eyedrops to reduce intraocular pressure in people with glaucoma.

  Effects on the uterus

  • Menstrual cramps: The uterine tissue produces prostaglandins responsible for menstrual cramps. Typically, a person experiences more pain at the beginning of a period, and the pain level reduces as the uterus sheds tissue. Taking nonsteroidal anti-inflammatory drugs (NSAIDs) blocks the effects of prostaglandins in the uterus, which may help ease period pain.
  • Pregnancy: In late pregnancy, the uterine tissues have increased numbers of prostaglandins — including PGE2 and PGE2a. They are likely responsible for uterine contractions that move the fetus through the birth canal during labor. For this reason, doctors may prescribe prostaglandin medications to induce childbirth.
  • Abortion: Misoprostol is prostaglandin medication doctors useTrusted Source for first trimester abortions. It stimulates uterine contractions, which can terminate a pregnancy. They may also prescribe the medication if someone has a pregnancy loss to help clear the uterus.

  • What happens when levels get too high?

    If an individual has high prostaglandins levels, it may cause health issues. One of the main issues is excessive inflammation, which can lead to:

    • arthritis
    • heavy menstrual bleeding
    • painful menstrual cramps

    Excessive prostaglandins are also involved in allergic reactionsTrusted Source.

    What happens when levels get too low?

    Some people do not produce enough prostaglandins — and this can also cause health complications — includingTrusted Source:

    • stomach ulcers
    • glaucoma
    • congenital heart disease in newborn babies
    • erectile dysfunction
    • pulmonary hypertension

    Treating uncontrolled prostaglandins levels in the body

    Doctors may recommend anti-inflammatory medications, such as aspirin and ibuprofen, to reduce the effects of prostaglandins in the body.

    These medications block the action of an enzyme called cyclooxygenase, which is responsible for producing prostaglandins.

    Depending on the effects of excessive prostaglandins, a doctor may also recommend other approaches. For example, oral contraceptives or birth control pills may help reduce prostaglandin production if someone has painful periods. The medications slow the growth of the tissue lining the uterus, which produces prostaglandins. These hormonal medications may reduce menstrual pain in most people who use them.

    When to contact a doctor

    If an individual experiences painful menstruation that does not improve with NSAIDs, they should consult a doctor.

    They may recommend hormonal birth control to help ease symptoms. They can also rule out other issues, such as endometriosis or uterine fibroids, that could cause painful menstruation.

    Summary

    Prostaglandins are hormone-like substances that the body produces. They play an important role in various bodily processes, including healing, pain, and inflammation. Individuals may experience health problems if their prostaglandin level is too high or too low.

    Excessive prostaglandins may lead to painful periods and heavy menstrual bleeding, whereas low levels can contribute to stomach ulcers and glaucoma.

    Nonsteroidal anti-inflammatory drugs (NSAIDs) help reduce the effect of prostaglandins in the body, and a doctor may recommend them for people with painful periods.

  • Source - Medical News Today

What to know about the sternothyroid

The sternothyroid muscle is present in the front region of the neck. It is part of the infrahyoid muscle group and aids functions such as swallowing and speech.

Certain health conditions may affect the sternothyroid muscle, or the infrahyoid muscle group, and can result in speaking, chewing, and swallowing difficulties.

This article explores the anatomy and functions of the sternothyroid and conditions that may affect the muscle.

Definition

The sternothyroid muscleTrusted Source is part of the infrahyoid muscle groupTrusted Source of the neck, along with the:

• omohyoid muscle
• sternohyoid muscle
• thyrohyoid muscle

The infrahyoid muscles are an anterior neck muscle group, which means they are present at the front of the neck. Some people may also refer to the infrahyoid muscle group as the strap musclesTrusted Source. This name refers to the muscles having a long and flat shape, similar to a belt or strap.

Anatomy

The sternothyroid muscleTrusted Source makes up a layer of the infrahyoid muscles, along with the thyrohyoid muscle. The sternohyoid and omohyoid muscles make up the superficial, or top, layer of the infrahyoid muscle group.

The sternothyroid attachesTrusted Source to the upper portion of the sternum, also known as the breastbone, and the thyroid cartilage, also known as the Adam’s apple. It overlies the superior, or upper, portion of the thyroid gland. The thyroid is a butterfly-shaped gland that sits in the front of the neck. It is responsible for regulating metabolism by producingTrusted Source substances such as thyroid hormones.

Connective tissue joins the sternothyroid and sternohyoid muscles. Doctors may refer to these two muscles as paired muscles. During some forms of surgery, a doctor may cut through this tissue. A surgeon will typically attempt to separate the left- and right-sided muscles but divide the connective tissue between them and spread them sideways.

Function

The role of the sternothyroid muscle is to depress the hyoid boneTrusted Source and the larynxTrusted Source during speech and swallowing, along with the other infrahyoid muscles. The hyoid boneTrusted Source refers to a small U-shaped bone, and the larynxTrusted Source is often known as the voice box. As such, the sternothyroid muscle plays a role in speaking, swallowing, and chewing by supporting and moving these structures.

The sternothyroid muscle, along with the other muscles of the infrahyoid muscle group, also contributes to protecting other important structures in the neck, such asTrusted Source:

• the esophagus
• blood vessels
• the thyroid gland
• the trachea

Health conditions  

• Conditions involving the sternothyroid muscle or the infrahyoid muscle group may affect various body functions, including speaking, chewing, and swallowing.

Dysphagia

• Dysphagia is the medical term to describe swallowing difficulties. A person who experiences dysphagia may have weaknessTrusted Source in the infrahyoid muscles, including the sternothyroid muscle. However, this is one of many possible causes of dysphagia, and isolated weakness of these muscles is quite rare.

Speaking difficulties

• Certain muscle conditions may result in the muscles of the neck region experiencing an imbalance in tension and causing issues with speech.

  Muscle tension dysphonia is a condition that causes the sound of a person’s voice to change and become difficult to understand. This results from excessive tension in the extrinsic muscles, such as the infrahyoid muscle group.

  This causes the larynx to have an improperTrusted Source position and creates tension in the vocal folds. Not only can this cause a change in a person’s voice, but it can also cause issues with swallowing and breathing and result in tenderness in the neck.

Masses in neck

• A leiomyomaTrusted Source, also known as a fibroid, is a type of smooth muscle tumor that presents more commonly in premenopausal females. Evidence suggests that approximately 12%Trusted Source of leiomyomas occur in the head and neck region. However, leiomyomas in the sternothyroid, or other strap muscles, are extremely rare. A person with leiomyoma in their sternothyroid muscle may feel a mass in their neck. The size of the mass may vary.

Muscle paralysis

• The ansa cervicalisTrusted Source describes a neural loop that supplies nerves to the sternothyroid, omohyoid, and sternohyoid muscles. As such, injury to the ansa cervicalis may result in infrahyoid muscle weakness or paralysis. A person with an ansa cervicalis injury may experience symptoms such asTrusted Source:

  • a hoarse voice
  • difficulty swallowing
  • tightness in the throat

  Injury may occur to the ansa cervicalis following surgery or due to trauma to the head or neck region.

Thyroid issues

• Some people may experience issues with their thyroid gland, including underactivity — hypothyroidism — or overactivity — hyperthyroidism. Muscle weakness can occur with both conditions, which may impact the sternothyroid. In some people, the thyroid gland may swell and enlarge. This is known as a goiter. Hypothyroidism and hyperthyroidism can both cause goiter.

  Goiter may affect the sternothyroid muscle as well as the other muscles of the infrahyoid muscle group. It may also compress other structures, such as the esophagus. A person with a goiter may experienceTrusted Source:

  • difficulty swallowing
  • a hoarse voice
  • a choking sensation
  • coughing
  • shortness of breath

Summary

• The sternothyroid is a muscle present at the front of the neck. It is one of the muscles that form the infrahyoid muscle group. The sternothyroid helps depress the hyoid bone and larynx, meaning it aids functions such as swallowing, speaking, and chewing. It also protects other important structures in the neck.

  Certain conditions may affect the sternothyroid, which can result in difficulty with swallowing, speaking, and chewing.

• Source - Medical News Today

The heart: All you need to know

    

The human heart is a finely-tuned instrument that serves the whole body. It is a muscular organ around the size of a closed fist, and it sits in the chest, slightly to the left of center.

The heart beats around 100,000 times a day, pumping approximately 8 pints of blood throughout the body 24/7. This delivers oxygen- and nutrient-rich blood to tissues and organs and carries away waste.

The heart sends deoxygenated blood to the lungs, where the blood loads up with oxygen and unloads carbon dioxide, a waste product of metabolism.

Together, the heart, blood, and blood vessels — arteries, capillaries, and veins — make up the circulatory system.

In this article, we explore the structure of the heart, how it pumps blood around the body, and the electrical system that controls it.

Anatomy of the heart

Below is an interactive 3D model of the heart. Explore the model using your mouse pad or touchscreen to learn more.

The heart consists of four chambers:

• The atria: These are the two upper chambers, which receive blood.
• The ventricles: These are the two lower chambers, which discharge blood.

A wall of tissue called the septum separates the left and right atria and the left and right ventricle. Valves separate the atria from the ventricles.

The heart’s walls consist of three layers of tissue:

• Myocardium: This is the muscular tissue of the heart.
• Endocardium: This tissue lines the inside of the heart and protects the valves and chambers.
• Pericardium: This is a thin protective coating that surrounds the other parts.
• Epicardium: This protective layer consists mostly of connective tissue and forms the innermost layer of the pericardium.

• How the heart works

  The rate at which the heart contracts depends on many factors, such as:

  • activity and exercise
  • emotional factors
  • some medical conditions
  • a fever
  • some medications
  • dehydration

  At rest, the heart might beat around 60 times each minute. But this can increase to 100 beats per minute (bpm) or more.
  

  Left and right sides

  The left and right sides of the heart work in unison. The atria and ventricles contract and relax in turn, producing a rhythmic heartbeat.

  Right side

  The right side of the heart receives deoxygenated blood and sends it to the lungs.

  • The right atrium receives deoxygenated blood from the body through veins called the superior and inferior vena cava. These are the largest veins in the body.
  • The right atrium contracts, and blood passes to the right ventricle.
  • Once the right ventricle is full, it contracts and pumps the blood to the lungs via the pulmonary artery. In the lungs, the blood picks up oxygen and offloads carbon dioxide.

  Left side

  The left side of the heart receives blood from the lungs and pumps it to the rest of the body.

  • Newly oxygenated blood returns to the left atrium via the pulmonary veins.
  • The left atrium contracts, pushing the blood into the left ventricle.
  • Once the left ventricle is full, it contracts and pushes the blood back out to the body via the aorta.

  Diastole, systole, and blood pressure

  Each heartbeat has two parts:

  Diastole: The ventricles relax and fill with blood as the atria contract, emptying all blood into the ventricles.

  Systole: The ventricles contract and pump blood out of the heart as the atria relax, filling with blood again.

  When a person takes their blood pressure, the machine will give a high and a low numberTrusted Source. The high number is the systolic blood pressure, and the lower number is the diastolic blood pressure.

  Systolic pressure: This shows how much pressure the blood creates against the artery walls during systole.

  Diastolic pressure: This shows how much pressure is in the arteries during diastole.

  Gas exchange

  When blood travels through the pulmonary artery to the lungs, it passes through tiny capillaries that connect on the surface of the lung’s air sacs, called the alveoli.

  The body’s cells need oxygen to function, and they produce carbon dioxide as a waste product. The heart enables the body to eliminate the unwanted carbon dioxide.

  Oxygen enters the blood and carbon dioxide leaves it through the capillaries of the alveoli.

  The coronary arteries on the surface of the heart supply oxygenated blood to the heart muscle.

  Pulse

  A person can feel their pulse at points where arteries pass close to the skin’s surface, such as on the wrist or neck. The pulse is the same as the heart rate. When you feel your pulse, you feel the rush of blood as the heart pumps it through the body.

  A healthy pulse is usually 60–100 bpmTrusted Source, and what is normal can vary from person to person.
  
  A very active person may have a pulse as low as 40 bpm. People with a larger body size tend to have a faster pulse, but it is not usually over 100 bpm.

• Valves

• The heart has four valvesTrusted Source to ensure that blood only flows in one direction:

  • Aortic valve: This is between the left ventricle and the aorta.
  • Mitral valve: This is between the left atrium and the left ventricle.
  • Pulmonary valve: This is between the right ventricle and the pulmonary artery.
  • Tricuspid valve: This is between the right atrium and right ventricle.

  Most people are familiar with the sound of the heart. In fact, the heart makes many types of soundTrusted Source, and doctors can distinguish these to monitor the health of the heart.
  
  The opening and closing of the valves are key contributors to the sound of the heartbeat. If there is leaking or a blockage of the heart valves, it can create sounds called “murmurs.”

• The heart’s electrical system

  To pump blood throughout the body, the muscles of the heart must work together to squeeze the blood in the right direction, at the right time, and with the right force. Electrical impulses coordinate this activity.

  The electrical signal begins at the sino-atrial node, sometimes called the sinus, or SA, node. This is the heart’s pacemaker, and it sits at the top of the right atrium. The signal causes the atria to contract, pushing blood down into the ventricles.

  The electrical impulse then travels to an area of cells at the bottom of the right atrium, between the atria and ventricles, called the atrioventricular, or AV, node.
  
  These cells act as a gatekeeper. They coordinate the signal so that the atria and ventricles do not contract at the same time. There needs to be a slight delay.

  From here, the signal travels along fibers, called Purkinje fibers, within the ventricle walls. The fibers pass the impulse to the heart muscle, causing the ventricles to contract.

  Blood vessels

  There are three types of blood vessels:

  Arteries: These carry oxygenated blood from the heart to the rest of the body. The arteries are strong, muscular, and stretchy, which helps push blood through the circulatory system, and they also help regulate blood pressure. The arteries branch into smaller vessels called arterioles.

  Veins: These carry deoxygenated blood back to the heart, and they increase in size as they get closer to the heart. Veins have thinner walls than arteries.

  Capillaries: These connect the smallest arteries to the smallest veins. They have very thin walls, which allow them to exchange compounds such as carbon dioxide, water, oxygen, waste, and nutrients with surrounding tissues.

  The heart, blood, and blood vessels make up the circulatory, or cardiovascular, system.
  

  Cardiac arrest: When the heart stops

  The heart is essential to life — if it stops beating, blood will not reach the brain and other organs, and the person can die within minutesTrusted Source. This is called cardiac arrest.

  If a person experiences cardiac arrest, they will be unable to speak or breathe, and they will have no heartbeat.

  Anyone nearby should call 911 immediately and start cardiopulmonary resuscitation (CPR), pressing hard and fast with locked hands on the center of the person’s chest.

  According to the Centers for Disease Control and Prevention (CDC), CPR can double or triple a person’s chance of survival after their heart stops.

  Conclusion

  The heart is an essential, powerful organ that constantly pumps oxygen and nutrients around the body.

  If a person is born with congenital heart disease, or if damage occurs due to illness or other factors, the heart’s function may diminish, and this can lead to life threatening complications, such as heart failure.

  Here, learn about preventing and treating different types of heart disease.

  If the heart stops, a person cannot survive for long. Staying active and maintaining a healthful diet are two ways to protect the heart.

• Source - Medical News Today