Transmembrane pressure refers to the difference in pressure across a semipermeable membrane. In renal physiology, transmembrane pressure plays a crucial role in fluid movement between blood vessels and renal tubules. It is determined by the balance between hydrostatic and osmotic pressure forces. Hydrostatic pressure, caused by the fluid’s height, pushes fluid out of the blood vessels and into the renal tubules. Osmotic pressure, caused by the concentration of dissolved solutes, draws fluid into the blood vessels. The interplay between these forces determines the net direction and rate of fluid movement, influencing glomerular filtration, reabsorption, and secretion processes in the kidneys.
