As a result of very low arterial blood pressure, what happens to glomerular hydrostatic pressure?
Low arterial pressure will diminish glomerular hydrostatic pressure (GHP) and this may negatively affect filtration of blood at Bowman's capsule. Kidneys may fail to produce urine in such case.
A small net filtration pressure (NFP) of 10 - 15 mm Hg develops in glomerular capillaries due to which filtration of blood takes place in kidney.
NFP = GHP (glomerular hydrostatic pressure) minus (colloidal osmotic pressure of blood + capsular hydrostatic pressure of filtrate)
Thus, decreased GHP means decreased NFP.