This Month's Highlights

[摘要] K+ secretion in the kidney and distal colon is a main determinant of K+ homeostasis and is familiar to the transport physiologist and clinician caring for patients with advanced chronic kidney disease. Sausbier and colleagues used a knockout mouse model and Ussing chambers to characterize the K+ secretory channel in the colon. The calcium-activated large conductance maxi-K (also called BK) channel appears to be the main player. Of note, this Ca2+-activated K+ secretory channel is also activated by purinergic receptor pathways and inhibited by barium. Understanding the biophysical features and regulation of expression and activity of this channel could lead to new approaches to maintaining K+ balance when kidney function is compromised. Kayexalate is not well suited for chronic ambulatory use; any suggestion of a better approach to maintaining potassium balance would be most welcome. See Sausbier et al., pages 1275–1282.

[学科分类] 泌尿医学

[关键词] Bone marrow necrosis;Sickle cell disease;Hyperhemolysis syndrome