Blood vessel Blood vessel The blood vessels are the part of the circulatory system, and microcirculation, that transports blood throughout the human body. These vessels are designed to transport nutrients and oxygen to the tissues of the body. They also take waste and carbon dioxide and carry them away from the tissues and back to the heart. Blood vessels are needed to sustain life as all of the body’s tissues rely on their functionality.There are three major types of blood vessels: the arteries, which carry the blood away from the heart; the capillaries, which enable the actual exchange of water and chemicals
Helicine arteries of penis in increased levels of cyclic guanosine monophosphate (cGMP). cGMP in turn triggers relaxation of the smooth muscle and results in dilation of blood vessels. This signal is terminated when cGMP is broken down by the enzyme cGMP specific phosphodiesterase type 5 (PDE5), the enzyme that is targeted by sildenafil and other drugs that treat erectile dysfunction. By preventing PDE5 from breaking down cGMP, the effects of NO are amplified and vasodilation occurs, thus resulting in increased penile erection. Helicine arteries of penis The helicine arteries of penis are arteries in the penis. They are found in the corpora cavernosa penis.