The glutathione levels are reduced in Goto-Kakizaki rat retina, but are not influenced by aminoguanidine treatment.
OBJECTIVE
To examine the levels of the free radical protecting enzyme glutathione and the endothelial/pericyte ratio in retinal capillaries in the Goto-Kakizaki (GK) Wistar rat, with and without aminoguanidine treatment.


METHODS
Eight-month-old GK rats, with non-obese, spontaneous non-insulin-dependent diabetes mellitus (NIDDM), were examined after a six month period of aminoguanidine treatment. Glutathione levels were measured with high performance liquid chromatography and the endothelial/pericyte ratio was calculated in trypsin digested vessel preparations.


RESULTS
The levels of glutathione in GK rat retina were significantly lower compared to controls (p = 0.0108). There was no difference in the endothelial/pericyte ratio compared to matched control rats (1.8 +/- 0.2 vs. 1.8 +/- 0.1, respectively). Aminoguanidine treatment did not influence either the degree of hyperglycemia, the levels of glutathione or the endothelial/pericyte ratio in GK or control rat retina.


CONCLUSIONS
The results indicate that impaired glucose metabolism may influence one of the defense mechanisms for oxidative stress, but also suggest that decreased glutathione levels occur prior to morphological signs of pericyte loss and/or endothelial cell proliferation in this animal model of hereditary NIDDM.
Agardh
C D
CD
Department of Internal Medicine, University Hospital, Lund, Sweden.
Agardh
E
E
Hultberg
B
B
Qian
Y
Y
Ostenson
C G
CG
D000818:Animals; D001835:Body Weight; D002851:Chromatography, High Pressure Liquid; D003924:Diabetes Mellitus, Type 2 / Q000150:complications / Q000378:metabolism*; D003930:Diabetic Retinopathy / Q000209:etiology / Q000378:metabolism*; D004730:Endothelium, Vascular / Q000378:metabolism; D005260:Female; D005947:Glucose / Q000378:metabolism; D005951:Glucose Tolerance Test; D005978:Glutathione / Q000378:metabolism*; D017127:Glycation End Products, Advanced / Q000037:antagonists & inhibitors*; D006146:Guanidines / Q000494:pharmacology*; D051381:Rats; D011922:Rats, Mutant Strains; D017208:Rats, Wistar; D012160:Retina / Q000187:drug effects / Q000378:metabolism*; D012171:Retinal Vessels / Q000378:metabolism
D017127:Glycation End Products, Advanced; D006146:Guanidines; D005978:Glutathione; D005947:Glucose; C004479:pimagedine