[Effects of monocular visual deprivation on parameters of GLuRs in visual cortex in developing kittens].
OBJECTIVE
To explore the molecular mechanism of the development of amplyopia.


METHODS
Lid suture was performed on 5 kittens at 3 weeks of age to produce monocular visual deprivation. Six kittens were used as controls without any treatment. Three months later, the characteristics of [3,4-3H]-glutamate binding to the visual cortical membranes of the kittens were studied using radiolabelled ligand receptor binding assay.


RESULTS
The kittens with monocular deprivation had decreased GluRs binding sites in the visual cortex as compared with the controls (P < 0.001). The kittens with monocular deprivation had greater value of KD than the controls (P < 0.001), indicating a decrease in the affinify of GluRs. The Hill coefficients of all of the kittens were close to 1, indicating that [3,4-3H]1-glutamate binded to a single-site receptor, obeying mass action law. Even if there were multi binding sites in GluRs, the affinity of these sites to [3,4-3H]1-glutamate was almost identical. Neither positive nor negative interactive effects existed.


CONCLUSIONS
Monocular deprivation does affect the binding parameters (KD and Bmax) of GluRs, which may be a molecular mechanism of the development of amblyopia.
Liu
Zheng
Z
Department of Ophthalmology, West China Hospital, Sichuan University, Chengdu, China.
Hou
Chuan
C
Chen
Man-Ling
ML
Ma
Lin
L
D000550:Amblyopia / Q000209:etiology / Q000378:metabolism* / Q000503:physiopathology; D000818:Animals; D000831:Animals, Newborn; D002415:Cats; D005260:Female; D008297:Male; D017470:Receptors, Glutamate / Q000235:genetics / Q000378:metabolism*; D012683:Sensory Deprivation / Q000502:physiology*; D015349:Vision, Monocular / Q000502:physiology*; D014793:Visual Cortex / Q000378:metabolism*
D017470:Receptors, Glutamate