بمناسبة قراءة محاضرة سادسة حيوية:
ص 3
حركة الماء الكلية عبر الأوعية الشعرية (من وإلى الوعاء) تنظم بعاملين:
1- ضغط الدم الذي يدفع السائل ليعبر عبر الشعيرات
2- الضغط الجرمي الناجم عن البروتينات وهذا شرح عنها:
oncotic pressure, or colloid osmotic pressure, is a form of osmotic pressure exerted by proteins in blood plasma that usually tends to pull water into the circulatory system.
Throughout the body, dissolved compounds have an osmotic pressure. Because large plasma proteins cannot easily cross through the capillary walls, their effect on the osmotic pressure of the capillary interiors will, to some extent, balance out the tendency for fluid to leak out of the capillaries. In other words, the oncotic pressure tends to pull fluid into the capillaries. In conditions where plasma proteins are reduced, e.g. from being lost in the urine (proteinuria) or from malnutrition, there will be a reduction in oncotic pressure and an increase in filtration across the capillary, resulting in excess fluid buildup in the tissues (edema).