Abstract: SA-PO547

Morphological and Morphometrical Analyses of Renal Tubules in Danio rerio Regarding Nephrogenesis

Session Information

  • Developmental Biology
    November 04, 2017 | Location: Hall H, Morial Convention Center
    Abstract Time: 10:00 AM - 10:00 AM

Category: Developmental Biology and Inherited Kidney Diseases

  • 401 Developmental Biology

Authors

  • Hochstuhl, Jasmin, Heidelberg University, Medical Faculty Mannheim, Mannheim, Germany
  • Islinger, Markus, Heidelberg University, Medical Faculty Mannheim, Mannheim, Germany
  • Elger, Marlies, Heidelberg University, Medical Faculty Mannheim, Mannheim, Germany
Background

Recent studies indentified functional markers for individual segments of the zebrafish pronephros and the definitive kidney. However, those studies largely lack direct correlations of segment markers with the substructure of the respective segment.

Methods

The pronephric kidney and the definitive kidney were studied in zebrafish, Danio rerio. We investigated larvae (72h), juveniles (26d) and adults (sexually mature fish). By using light and transmission electron microscopy as well as fluorescence labeled lectins, we established criteria for identification of nephron segments, cell types and their substructure.

Results

The pronephric kidney consists of six segments: neck segment (NS), first proximal tubule (PI), second proximal tubule (PII), early distal tubule (EDT) and late distal tubule (LDT), followed by a short collecting tubule.
The nephrons of the definitive kidney showed the same sequence of segments as found in the pronephric kidney. However, in fully developed nephrons the second proximal tubule (PII) could be subdivided into two parts (PIIa and PIIb). For every segment, distinct morphological and morphometrical criteria could be identified.
Based on segment location and cellular substructure, in most cases the major function of the segments could be assumed by comparison with physiological data of the respective segments in fish and mammals.
Measurements of segment length and epithelial height allowed to classify different developmental stages of the entire nephron and of individual nephron segments.
Nephron anlagen of different developmental stages were found exclusively apposed to the pronephric duct and the collecting duct. In all cases the prospective distal end of the anlagen invaded the pronephric duct or the collecting duct, respectively.

Conclusion

This study presents comprehensive morphological data of the tubular substructure of the pronephros and the definite kidney and may serve as a structural basis for the investigations dealing with transport mechanisms and renal disorders in this established model organism.