This study was designed to examine the effect of alterations in potassium ingestion on the cellular morphology of the collecting tubular system. Particular emphasis was placed on determining the best method for quantitating collecting tubule cell types. Charles River rats were studied after 4 weeks of ingesting a diet with normal, high, or zero potassium content. The collecting tubule was divided into five zones (surface through papilla), and 200 cells in each zone from five rats in each group were identified by light (LM) and scanning electron (SEM) microscopy. After potassium depletion, no change in the percentage of dark cells was noted by LM but by SEM dark cells increased from about 7 to about 30% in all areas of the cortex and from less than 1% to about 18% in the medulla. Intermediate cells were increased when examined with both LM and SEM in the cortex and the medulla. A partial explanation for the difference in the percentage of dark cells by LM and SEM became apparent during examination by transmission electron microscopy. Many cells had apical surface characteristics of dark cells but a cytoplasm characteristic of light cells and thus would have been called intermediate cells using LM. the high potassium diet was associated with a marked decrease in dark cells throughout the cortex by both LM and SEM. We conclude that there appears to be a reciprocal relationship between the number of dark cells and dietary potassium. These findings may reflect a morphologic relationship. Quantitation of dark cells is done best by SEM, at least in potassium-deprived rats.
|Original language||English (US)|
|Number of pages||8|
|State||Published - Jan 1 1980|
ASJC Scopus subject areas
- Pathology and Forensic Medicine
- Molecular Biology
- Cell Biology