Question

Nitric oxide (NO) is a gaseous molecule with lipid solu- bility similar to that of O2 and CO2. Endothelial cells lining arteries use NO to signal surrounding smooth muscle cells to relax, thereby increasing blood flow. What mechanism or mechanisms would transport NO from where it is produced in the cytoplasm of an endothelial cell into the cytoplasm of a smooth muscle cell, where it acts?

Answer 1

`NO` passively diffuses down its concentration gradient through the endothelial cell plasma membrane out of the cell and then passiveley diffuses through the plasma membrane into the cytoplasm of the smooth muscle cell, where it acts to decrease contraction.

Step-by-step explanation:

Hello,

At first, we must consider that
`O_2` and
`CO_2`,
`NO` passively diffuses through membranes. As it is produced by an enzyme and accumulates in the endothelial cell cytosol,
`NO` passively diffuses down its concentration gradient through the endothelial cell plasma membrane out of the cell and then passiveley diffuses through the plasma membrane into the cytoplasm of the smooth muscle cell, where it acts to decrease contraction.

Best regards