A link between fertility and K+ homeostasis: role of the renal H,K-ATPase type 2

作者：Salhi Amel; Lamouroux Christine; Pestov Nikolay B; Modyanov Nikolai N; Doucet Alain; Crambert Gilles^*

来源：Pflugers Archiv-European Journal of Physiology, 2013, 465(8): 1149-1158.

DOI：10.1007/s00424-013-1252-x

• Pregnancy
• Kidney
• Renal ion transport
• Plasma K+ concentration
• Colonic and nongastric H,K-ATPase

Renal K+ retention is activated during pregnancy through a mechanism unknown to date. Here, we showed that the renal stimulation of H,K-ATPase type 2 (HKA2), whose expression was recently identified to be progesterone-dependent, is part of the mechanism favoring K+ accumulation during gestation. Moreover, investigation of the gestational phenotype of HKA2-null mice compared to their wild-type (WT) littermate revealed a decrease in fertility (gestation was successful in 33 % of HKA2-null mice vs. 83 % of WT mice) and in litter size (6.5 +/- 0.6 and 7.8 +/- 0.4 fetuses per litter, respectively). We also observed that urinary K+ excretion decreased by 20 % and plasma K+ concentration rose slightly (11 %) in WT mice during gestation (relative to basal conditions). In contrast, the renal excretion of K+ and plasma K+ levels in HKA2-null mice remained constant during gestation, whereas fecal K+ excretion increased. As a consequence, HKA2-null mice did not accumulate K+ in their extracellular compartment as efficiently as WT mice did. Finally, the link between inefficient K+ balance adaptations and gestational complications was established when we observed that these complications could be reversed with an increased K+ uptake. Altogether, these results define a novel physiological role for the HKA2 transporter and uncover a link between K+ metabolism and fertility.

• 出版日期2013-8