It is this cycle that causes what we think of as every day hair loss -- most people lose between 50 to 100 hairs each day. And on days when we shampoo, we tend to lose more, says Amy McMichael, M.D., a professor of dermatology at Wake Forest Baptist Health.
1 Cells where infection or other damage is occurring release substances like histamine that dilate the arterioles and thus increase blood flow in the area. [ 2  Link to discussion of inflammation. ]. 3  In most of the body, the flow of blood through a capillary is controlled by the arteriole supplying it.ontrol of the Capillary Beds. An adult human has been estimated to have some 60,000 miles (96,560 km) of capillaries with a total surface area of some 800â1000 m 2 (an area greater than three tennis courts). The total volume of this system is roughly 5 liters, the same as the total volume of blood.
They found that smooth muscle cells on precapillary arterioles clamped down on vessels in response, blocking the flow of red blood cells to downstream tissues. In many cases, the vessels remained constricted after the researchers removed the ligature and restored arterial blood flow.hey concluded that flow is exclusively controlled by smooth muscle cells surrounding the larger arterioles, which make up less than 10 percent of the brainâs blood vessels. These cells also regulated blood flow increases in response to brain activity, which form the basis for functional MRI.