The renin-angiotensin system (RAS) is a master regulator of blood pressure and fluid homeostasis. This system is a multi-enzymatic cascade in which angiotensinogen, the major substrate, is processed in a two-step reaction by renin and angiotensin-converting enzyme (ACE), resulting in…
In recent years, there has been an explosion of discovery about proteins that function to organize components of the signal transduction machinery with their effectors at specific subcellular locales. Many of these molecular scaffolds control the assembly, trafficking, subcellular location…
The successful transition from single cells to complex multicellular organisms has required the development of mechanisms for cells to communicate with each other, so as to act in concert during processes such as nutrient acquisition, motility, and defense. The most…
Intercellular junctions are relatively static regions of cell–cell contact found between epithelial, endothelial and mesothelial cells that have various functions. The morphology of the junctional complex in epithelia was defined by Farquhar and Palade in 1963, Farquhar MG, Palade GE.…
The primary or immotile cilium is a nearly ubiquitous microtubule-based structure. It was once considered a vestigial remnant; however, recent advances have revealed that the cilium functions as a critical sensory and signaling center allowing cells to respond efficiently to…
This chapter will cover discussions on principles of external balance for electrolytes, and for acids and bases. The first section will deal with discussions on principles of electrolyte balance in general, and the second section discusses the acid–base balance. This…
Exchange through microvascular walls is both the initial and the final step of transport of materials by the circulation. In most tissues, microvascular exchange is a passive process, driven by differences in hydrostatic pressure and solute concentration between the circulating…
The purposes of this chapter are to explain what an ion channel is and how it works, provide an overview of the contribution ion channel proteins make to renal transport, and suggest how changes in the structure and biophysical properties…
In this chapter we discuss electrophysiological approaches to the study of renal function. The purpose is to provide an overview of the available techniques, with particular emphasis on what can be learned using the latest methods. However, the chapter is…
The kidney uses a large amount of energy, most of which are dedicated to solute reabsorption, especially Na + , from glomerular filtrate. Reabsorption of Na + drives the cellular and paracellular transport of water and other solutes. The mechanisms…