Actin cytoskeletal and functional studies of the proximal convoluted tubules after preservation.
BACKGROUND
Proximal tubule cells have specialized apical membranes with microvilli that provide an extensive surface area for unidirectional transport of solute from lumen to blood. The major structural solute component is F-actin, which interacts with transmembrane proteins, including ion transport molecules related to normal absorptive and secretory functions. Our study was to evaluate F-actin and fluid absorption (Jv) in proximal tubules after exposure to preservation solutions.


METHODS
In vitro microperfusion technique and immunohistochemistry analysis.


RESULTS
1. Absorptions were similar in 1- and 24-hour-preserved tubules, as well as in fresh tubules. The exception was tubules for 24 hours in Euro-Collins solution, which did not show absorption, suggesting that it was affected. 2. Fluorescence intensity of actin tubules preserved for 1 hour in both solutions showed similar values to each other and to the control group; tubules preserved for 24 hours in both solutions were similar to each other, although statistically different than the control group and those preserved for 1 hour in Belzer (UW) solution.


CONCLUSIONS
There were differences among groups in the distribution of F-actin; Jv values were different for 24-hour preservation in each solution, whereas fluorescence intensity was similar in both 24-hour solutions. Thus, actin cytoskeleton was not responsible for it, because 24-hour preservation in UW showed Jv results comparable to the control group.
Figueiredo
J F
JF
Organ Preservation Laboratories, Faculty of Medical Sciences, State University of Campimas, Unicamp, Brazil.
Bertels
I M V
IM
Gontijo
J A R
JA
D000042:Absorption; D008841:Actin Cytoskeleton / Q000187:drug effects / Q000648:ultrastructure; D000199:Actins / Q000502:physiology* / Q000648:ultrastructure; D000241:Adenosine / Q000494:pharmacology; D000493:Allopurinol / Q000494:pharmacology; D000818:Animals; D003599:Cytoskeleton / Q000187:drug effects / Q000502:physiology* / Q000648:ultrastructure; D005978:Glutathione / Q000494:pharmacology; D007328:Insulin / Q000494:pharmacology; D007685:Kidney Tubules, Collecting / Q000187:drug effects / Q000502:physiology / Q000648:ultrastructure; D007687:Kidney Tubules, Proximal / Q000187:drug effects / Q000502:physiology* / Q000648:ultrastructure; D008297:Male; D018613:Microscopy, Confocal / Q000379:methods; D008871:Microvilli / Q000187:drug effects / Q000648:ultrastructure; D023421:Models, Animal; D009926:Organ Preservation / Q000379:methods*; D019188:Organ Preservation Solutions / Q000493:pharmacokinetics / Q000494:pharmacology*; D010477:Perfusion / Q000379:methods; D011817:Rabbits; D011887:Raffinose / Q000494:pharmacology
D000199:Actins; D007328:Insulin; D019188:Organ Preservation Solutions; C055206:University of Wisconsin-lactobionate solution; D000493:Allopurinol; D005978:Glutathione; D000241:Adenosine; D011887:Raffinose