Alteration of Akt, p-Akt, ERK, and p-ERK Proteins Expression in the Kidney of Hypokalemic Rat.
10.11637/kjpa.2017.30.3.87
- Author:
Choon Sang BAE
1
;
Hye Jung CHO
;
Kyu Yoon AHN
Author Information
1. Department of Anatomy, College of Medicine, Jeonnam University, Korea. kyahn@jnu.ac.kr
- Publication Type:Original Article
- Keywords:
Hypokalemia;
Metabolic alkalosis;
Akt;
p-Akt;
ERK;
p-ERK;
Immunohistochemisty
- MeSH:
Alkalosis;
Animals;
Blotting, Western;
Diet;
Extremities;
Hypokalemia;
Ion Channels;
Ion Transport;
Kidney*;
NF-E2-Related Factor 2;
Phosphorylation;
Phosphotransferases;
Rats*;
Signal Transduction;
Transcriptional Activation
- From:Korean Journal of Physical Anthropology
2017;30(3):87-98
- CountryRepublic of Korea
- Language:Korean
-
Abstract:
Hypokalemia causes metabolic alkalosis and morphological changes of the kidney. K⁺ balance is regulated not only by ion channels or pump gene, but also by various genes including NF-E2-related factor 2 (Nrf2). Previous study suggested the possibility that Akt and ERK kinase may be involved in Nrf2 transcriptional gene activation. In present study, we investigate the alterations of Akt, p-Akt, ERK, p-ERK protein in both normal kidney and K⁺-deficient diet kidney using Western blot analysis, and immunohistochemisrty. Our western blot data showed that the expression of Akt and p-Akt was increased gradually in K⁺-depleted diet (from 1W-3W) compared to normal group. The expression of ERK and p-ERK was markedly increased in K⁺-depleted diet 2W in comparison with normal group. Based on our immunostaining results, Akt protein immunoreactivity was prominently increased in outer medullary collecting duct, especially in K⁺-depleted diet 2 weeks. The localization of p-Akt proteins in K⁺-depleted groups was not different from normal group, but the immunoreactivity was significantly increased in distal convoluted tubule, macula densa and outer medullary thick ascending limb in K⁺-depleted diet 1 and 2 weeks groups. ERK protein immunoreactivity was prominently increased in outer medullary collecting duct, especially in K⁺-depleted diet 2 and 3 weeks. The localization of p-ERK proteins in K⁺-depleted groups was not different from normal group, but the immunoreactivity was prominently increased in the nucleus of outer medullary collecting duct especially in K⁺-depleted diet 2 weeks. Taken together, we suggest that the expression of p-Akt was gradually increased in K⁺-depleted groups of kidney, but the expression of p-ERK was markedly increased in K⁺-depleted diet 2 week group. Hence, the promotion of AKT and ERK phosphorylation in hypokalemic condition may be involved in the regulation of ion channels, ion transporters and subsequent intracellular signal transduction.
