2000 Fiscal Year Final Research Report Summary
Receptor density in monocularly deneruated rats
| Project/Area Number |
11671726
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (C)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 一般 |
|---|
| Research Field |
Ophthalmology
|
|---|
| Research Institution | Tokyo Medical and Dental University |
|---|
Principal Investigator |
KIYOSAWA Motohiro Tokyo Med & Dent Univ. Graduate School. Dept of Visual Science and Ophthalmology, Tokyo Medical and Dental University, Associate Professor, 大学院・医歯学総合研究科, 助教授 (20169957)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
MORI Hiroshi Tokyo Med & Dent Univ. Graduate School. Dept of Visual Science and Ophthalmology, Tokyo Medical and Dental University, Assistant (Jyosyu), 医学部・附属病院, 助手 (50302849)
|
|---|
| Project Period (FY) |
1999 – 2000
|
| Keywords | Period of Sceptibility / rat / enucleation / Visual Cortex / glucose metabolism / receptor density / autoradiogram / neural plasticity |
|---|
| Research Abstract |
PURPOSE.To study the changes in adenosine A1 and benzodiazepine receptors and glucose metabolism in the visual structures of rats following monocular deprivation by enucleation and eyelid suture at postnatal day 10.
METHODS.The right eye of rats were deprived by enucleation or eyelid suture and ex vivo autoradiography of the brain was performed at different times up to 45 days after the treatment. [1-methyl-1 1C]8-dicyclopropylmethyl-1-methyl-3-propylxanthine ([11C]MPDX) and [11C]flumazenil were used to map adenosine A1 receptors and benzodiazepine, respectively, and glucose metabolism was evaluated with [14C]2-deoxyglucose, and. The receptor-specific binding for 11C activity and the uptake of 14C activity in the superior colliculus (SC), visual cortex (VC) and dorsal lateral geniculate body (DLG) were determined.
RESULTS.The specific binding of [11C]MPDX to the adenosine A1 receptors in the contralateral SC significantly decreased immediately after enucleation and remained low thereafte
… More
r, whereas the specific binding of [11C]flumazenil to benzodiazepine receptors in the contralateral SC increased after 5 days. The uptake of [14C]2-deoxyglucose in the SC was depressed only one day after enucleation and then returned to the ipsilateral level. No significant difference between contralateral and ipsilateral sides was found in any other visual structures at any time investigated for the all three tracers. On the other hand, after the eyelid suture all three tracers showed symmetrical images without any detectable changes.
CONCLUSIONS.The axon degeneration related a decrease of the adenosine A1 receptor density resulted in an upregulation of postsynaptic benzodiazepine receptor density in monoculaely enucleated, not in eyelid sutured, rats at PN 10. Neither visual deprivation methods induced alteration in both receptors nor in glucose metabolism in any visual structures, except that the glucose metabolism was decreased only in the contralateral SC one day after the enucleation. These results suggest that the benzodiazepine receptors are susceptible to degeneration of presynaptic nerve terminals, but not to visual deprivation, and that the visual functions are not determined in rats at PN 10. Less
|
-
-
-
-
-
-
-
-
-
-
[Publications] Mishina M, Senda M, Kiyosawa M, De Volder AG, Toyama H, Ishiwata K, Oda K1, Kimura Y, Nakano H, Ohyama M, Kitamura S, Katayama Y.: "Benzodiazepine receptor distribution and cerebral blood flow in early blindness-a pet study-"Keio Journal of Medicine.. 49 Suppl 1. A114-116 (2000)
Description
「研究成果報告書概要(欧文)」より
-
[Publications] Yokota T, Uchihara T, Kumagai J, Shiojiri T, Pang JJ, Arita M, Arai H, Hayashi M, Kiyosawa M, Okeda R, Mizusawa H.: "A postmortem study of Friedreich-like ataxia with retinitis pigmentosa by mutation of alpha-tocopheroltransfer protein gene"J Neurol Neusosueg Psychiatry. 68 (4). 521-5 (2000)
Description
「研究成果報告書概要(欧文)」より
-
-
-
-
-
-
[Publications] Devolder AG, Toyama H, Kimura Y, Kiyosawa M, Nakano H, Vanlierde A, Wanet-Defalque M-C, Mishina M, Oda K, Ishiwata K, Senda M: "Auditory triggered mental imagery of shape involves visual association areas in early blind humans"Neuroimaging. (in press).
Description
「研究成果報告書概要(欧文)」より
