[Organic diseases and circulation. Pulmonary artery system in idiopathic pulmonary hypertension]

Phosphodiesterase 5 (PDE5) inhibitors are potent enzymes that function to hydrolyze cyclic nucleotides to their corresponding 5' monophosphates. Their unique biochemical properties have been applied in treating Pulmonary Arterial Hypertension (PAH).
Among the PDE5 inhibitors, sildenafil (Revatio) stands out as a competitive and selective inhibitor. It operates by elevating cellular levels of cGMP and augmenting signaling through the cGMP-PKG pathway, promoting vasodilation. Upon oral...

The pulmonary circulation is a vital system in our body that acts as a bridge between the respiratory and cardiovascular systems. It serves as a transport network for deoxygenated blood from the heart to the lungs and then returns oxygen-rich blood back to the heart.
The process begins with the right ventricle of the heart pumping deoxygenated blood into the pulmonary trunk. This large vessel extends about 5 centimeters before splitting into the left and right pulmonary arteries. These arteries...

Endothelins (ETs) are potent vasoactive peptides critical in the human body's various physiological and pathological processes. One of the most promising therapeutic strategies for treating pulmonary arterial hypertension (PAH) involves counteracting the effects of these endothelins using a class of drugs known as endothelin receptor antagonists.
ETs are synthesized through a complex sequence of enzymatic steps, primarily involving an enzyme referred to as endothelin-converting enzyme...

Prostacyclin receptor agonists are a class of therapeutic agents integral to managing pulmonary arterial hypertension (PAH). These drugs operate by mimicking the action of prostaglandin I2, or PGI2, a naturally occurring compound in the body.
These agonists bind to the IPR receptor situated on the plasma membrane of the pulmonary artery smooth muscle cells. This binding triggers a cascade of reactions known as the GS-AC-cAMP-PKA pathway. This pathway results in the relaxation of smooth muscle...

The systemic and pulmonary circuits are crucial components of the circulatory system, working together to transport blood between the heart, lungs, and the rest of the body. The process begins with pulmonary circulation, where deoxygenated blood is pumped from the right ventricle to the lungs via the pulmonary trunk and arteries. Upon reaching the lungs, the blood becomes oxygenated and returns to the heart, specifically to the left atrium, via the pulmonary veins.
The oxygenated blood is sent...

Pulmonary hypertension (PH) is a severe health condition in which the mean pulmonary arterial pressure increases to 25 mmHg or more, even when the body is at rest. This high pressure in the blood vessels that transport blood from the heart to the lungs can cause various symptoms, including shortness of breath, can lead to right heart failure, and significantly affect the overall quality of life.
There are various classifications for PH, each relating to different underlying causes and also...