Histological changes In renal tubules after ischemia – reperfusion Experimental studies

number: 
1434
English
department: 
Degree: 
Imprint: 
Medicine
Author: 
Maha Muhanad AlRezaly
Supervisor: 
Dr. Anisah A. Shareef
year: 
2006

Abstract:

Ischemia – reperfusion injury is a complex phenomenon that results in cell damage through a biphasic process. Ischemia initiates the injury by a decrease or complete loss of energy supply needed to maintain homeostasis. This by itself may lead to cellular dysfunction and death. Reperfusion increases cellular damage by a variety of proposed mechanisms such as inflammatory reaction and release of oxygen free radicals.Tissue injury resulting from I-R insult can result in both pathological cell death (necrosis) and programmed cell death (apoptosis) in human and experimental models of renal ischemia and ischemia-reperfusion. This study is an attempt to investigate the effect of ischemia and ischemia-reperfusion on the histology of the renal tubule. Thirty male rats (Rattus norvegicus albinus) were divided into six groups: control group, ischemia group (40 minute clamping of renal artery) and ischemia – reperfusion group (the removal of renal clamping after 1, 3, 6, and 24 hours) .H&E and PAS stain of kidney sections were used to demonstrate the change in the general morphological feature of renal tubular cells after following ischemia and ischemia – reperfusion injury. Methylene blue stain with semithin section and AO fluorescence dye were used for the morphological assessment of apoptosis. It was found that kidney tubule injury started after 40 minutes of ischemia by loss of brush border, vacuoles of various size appeared with flattening and dilation of the tubule, with condensation of nuclear chromatin. The damage was exacerbated after one hour reperfusion and reaches its peak after three hours of reperfusion. The process of recovery in tubular cells starts after six hour of reperfusion. Many tubular cells appear normal in shape after 24 hours of reperfusion. Although some nuclei appeared with condensed chromatin and nuclear fragmentation in apoptotic tubular cells. In conclusion, ischemia and ischemia – reperfusion of rat kidney in vivo resulted in apoptotic morphological changes of tubule cells. As the degree of renal tubular damage depend on the severity of ischemia, the ischemia procedure applied in the present study is most likely of moderate severity.