Change of melanocortin receptor expression in rat kidney ischemia-reperfusion injury.
OBJECTIVE
alpha-Melanocyte stimulating hormone (alpha-MSH) may ameliorate renal ischemia-reperfusion (I/R) injury. Recent data suggest that melanocortin receptors may be related to the anti-inflammatory and immunomodulating action for alpha-MSH. We designed this experiment to determine the renal distribution of alpha-MSH receptors; melanocortin-1 receptor (MC-1R) and melanocortin-3 receptor (MC-3R).


METHODS
Sprague-Dawley male rats (n = 24) were randomly divided into 2 groups: the sham (n = 2) and the operation groups with warm ischemia (n = 12). Animals in the operation group were subjected to 40 minutes of warm renal ischemia. Western blotting analyses and immunohistochemistry were employed to determine expression of MC-1R and MC-3R.


RESULTS
Expression of MC-1R and MC-3R was decreased on 1 day after reperfusion. Immunohistochemical study confirmed the findings of Western blot analysis.


CONCLUSIONS
The present study demonstrated novel renal expression of MC-1R and MC-3R, especially in the outer medulla, representative of the renal I/R injury. Our current study suggested that the mechanisms of action of alpha-MSH may significantly attenuate the renal I/R injury by specific kidney-targeted effects via MC-Receptors as well as by systemic cytokine effects.
Lee
Y S
YS
Division of Nephrology, the Eulji University Hospital, Seoul, South Korea. visionjcys@eulji.ac.kr
Park
J J
JJ
Chung
K Y
KY
D000818:Animals; D007150:Immunohistochemistry; D008297:Male; D053486:Melanocortins / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D044102:Receptor, Melanocortin, Type 1 / Q000235:genetics* / Q000378:metabolism; D044104:Receptor, Melanocortin, Type 3 / Q000235:genetics* / Q000378:metabolism; D012079:Renal Circulation / Q000502:physiology; D015427:Reperfusion Injury / Q000235:genetics* / Q000378:metabolism
D053486:Melanocortins; D044102:Receptor, Melanocortin, Type 1; D044104:Receptor, Melanocortin, Type 3