Alteration of the GABAergic neuronal system of the retina and superior colliculus in streptozotocin-induced diabetic rat.
Diabetes mellitus (DM) often causes neural dysfunctions, including visual disorders. To investigate the effect of hyperglycemia on the visual system, we studied the metabolism of gamma-aminobutyric acid (GABA), a major inhibitory neurotransmitter that has an important role in visual functions. We determined the GABA content and activities of glutamate decarboxylase (GAD) and GABA transaminase (GABA-T) in the retina and superior colliculus (SC) in streptozotocin (STZ)-induced DM rats. The GABA content and activities of GAD and GABA-T were decreased in the retinas of STZ-treated rats. The GABA content and GAD activity were reduced in the SC of STZ-treated rats, whereas GABA-T activity showed no marked change. This GABA reduction in the diabetes may be correlated with visual dysfunctions.
Honda
M
M
Department of Physiology, Kobe University School of Medicine.
Inoue
M
M
Okada
Y
Y
Yamamoto
M
M
D000612:4-Aminobutyrate Transaminase / Q000378:metabolism*; D000818:Animals; D003921:Diabetes Mellitus, Experimental / Q000150:complications / Q000378:metabolism*; D003930:Diabetic Retinopathy / Q000209:etiology / Q000378:metabolism; D004195:Disease Models, Animal; D005968:Glutamate Decarboxylase / Q000378:metabolism*; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D012160:Retina / Q000378:metabolism*; D012680:Sensitivity and Specificity; D013477:Superior Colliculi / Q000378:metabolism*; D005680:gamma-Aminobutyric Acid / Q000378:metabolism*
D005680:gamma-Aminobutyric Acid; D000612:4-Aminobutyrate Transaminase; D005968:Glutamate Decarboxylase