Proposed mechanism in the change of cellular composition in the outer medullary collecting duct during potassium homeostasis.
Histol Histopathol
; 27(12): 1559-77, 2012 12.
Article
en En
| MEDLINE
| ID: mdl-23059887
ABSTRACT
Potassium depletion (Kâº-D) induces hypertrophy and hyperplasia of collecting duct cells, and potassium repletion (Kâº-R) induces regression of these changes. The purpose of this study was to examine the time courses of the changes in cellular composition, the origin of intercalated cells (ICs) and the mechanism responsible for these changes. SD rats received Kâº-depleted diets for 1, 7, or 14 days. After Kâº-D for 14 days some of the rats received normal diets for 1, 3, 5, or 7 days. In the inner stripe of the outer medulla, Kâº-D increased significantly the number and proportion of Hâº-ATPase-positive ICs, but decreased the proportion of Hâº-ATPase-negative principal cells (PCs). However, proliferation was limited to Hâº-ATPase-negative PCs. During Kâº-R, the cellular composition was recovered to control level. Apoptosis increased during Kâº-R and exclusively limited in Hâº-ATPase-negative PCs. Double immunolabeling with antibodies to PC and IC markers identified both cells negative or positive for all markers during both Kâº-D and Kâº-R. Electron microscopic observation showed that ultrastructure of AE1-positive some cells were similar to AE1-negative some cells during Kâº-R. LC3 protein expression increased significantly and autophagic vacuoles appeared particularly in PCs on days 14 of Kâº-D and in ICs on days 3 of Kâº-R. These results suggest that PCs and ICs may interconvert in response to changes in dietary K+ availability and that autophagic pathways may be involved in the interconversion.
Texto completo:
1
Colección:
01-internacional
Asunto principal:
Potasio
/
Médula Renal
/
Túbulos Renales Colectores
Límite:
Animals
Idioma:
En
Revista:
Histol Histopathol
Asunto de la revista:
HISTOLOGIA
/
PATOLOGIA
Año:
2012
Tipo del documento:
Article