Template:Aquatic layer topics. An abyssal plain is an underwater plain on the deep ocean floor, usually found at depths between 3000 and 6000 m. Lying generally between the foot of a continental rise and a mid-ocean ridge, abyssal plains cover more than 50% of the Earth âs surface.
Murad discovered in 1977 that nitroglycerin and related artery-widening compounds act by releasing nitric oxide. Furchgott later concluded that cells in the inner lining of blood vessels secrete some unknown substance that makes vessels dilate.
The vasodilatory actions of nitric oxide play a key role in renal control of extracellular fluid homeostasis and is essential for the regulation of blood flow and blood pressure. NO also plays a role in erection of the penis and clitoris.