Neuroreceptor bindings and synaptic activity in visual system of monocularly enucleated rat.

Jpn J Ophthalmol

Department of Ophthalmology and Visual Science, Tokyo Medical and Dental University, Graduate School, Tokyo, Japan.

Published: June 2001

Purpose: To study the changes in the distribution of postsynaptic benzodiazepine (BDZ) and presynaptic adenosine A(1) (AA(1)) receptors in the superior colliculus (SC) and visual cortex (VC) of rats following monocular enucleation.

Methods: The right eyes of 6-week-old Long-Evans rats were enucleated and ex vivo autoradiography was performed on the SC and VC obtained at different times up to 8 weeks after the enucleation. [14C]deoxyglucose was used to detect glucose metabolism, and [11C]flumazenil and [1-methyl-(11)C]8-dicyclopropylmethyl-1-methyl-3-propylxanthine ([11C]MPDX) were used to map BDZ and AA(1) receptors, respectively. The receptor-specific binding for 11C was determined, and 11C and 14C activities were evaluated separately in the same tissue by a double tracing method.

Results: The uptake of [14C]deoxyglucose in the SC was depressed immediately after enucleation and gradually recovered. The binding of [11C]flumazenil to BDZ receptors in the contralateral SC was increased at week 2, and then returned to the pre-enucleation levels. The uptake of [11C]MPDX by the AA(1) receptors in the contralateral SC decreased by about 67% on day 5 after enucleation and remained low thereafter. In the contralateral VC, the uptake of [14C]deoxyglucose decreased immediately after the enucleation followed by a gradual recovery, whereas the uptake of [11C]flumazenil and [11C]MPDX was not altered.

Conclusions: The axon degeneration related decrease of the AA(1) receptor density resulted in a transient up-regulation of postsynaptic BDZ receptor density in monocularly enucleated adult rats. These results suggest that these radioligands can be used to study the distribution of the postsynaptic BDZ and presynaptic AA(1) receptors in the visual system and can probably be applied to the human visual system for positron emission tomography.

Download full-text PDF

Source
http://dx.doi.org/10.1016/s0021-5155(01)00329-xDOI Listing

Publication Analysis

Top Keywords

aa1 receptors
16
visual system
12
monocularly enucleated
8
distribution postsynaptic
8
bdz presynaptic
8
uptake [14c]deoxyglucose
8
receptors contralateral
8
receptor density
8
postsynaptic bdz
8
bdz
5

Similar Publications

Article Synopsis
  • This study examines the tolerance development to opioids, focusing on fentanyl and a new μ-opioid receptor agonist, NFEPP, which is activated in acidic environments typical of inflammation.
  • Researchers conducted tests on mice with colitis to assess the analgesic effects and tolerance of both opioids over five days.
  • Results showed that while fentanyl led to tolerance and cross-tolerance, NFEPP did not, suggesting it could offer pain relief without the risk of escalating dosages and increased side effects.
View Article and Find Full Text PDF

Introduction: Oxysterol-binding protein (OSBP) is known for its crucial role in lipid transport, facilitating cholesterol exchange between the Golgi apparatus and endoplasmic reticulum membranes. Despite its established function in cellular processes, its involvement in coronavirus replication remains unclear.

Methods: In this study, we investigated the role of OSBP in coronavirus replication and explored the potential of a novel OSBP-binding compound, ZJ-1, as an antiviral agent against coronaviruses, including SARS-CoV-2.

View Article and Find Full Text PDF

Activin signaling is essential for proper embryonic, skeletal muscle, and reproductive development. Duplication of the pathway in teleost fish has enabled diversification of gene function across the pathway but how gene duplication influences the function of activin signaling in non-mammalian species is poorly understood. Full characterization of activin receptor signaling pathway expression was performed across embryonic development and during early skeletal muscle growth in rainbow trout (RBT, Oncorhynchus mykiss).

View Article and Find Full Text PDF

Purpose: Extracellular heat shock protein 90 AA1(eHSP90α) is intricately linked to tumor progression and prognosis. This study aimed to investigate the difference in the value of eHSP90α in post-treatment response assessment and prognosis prediction between exon 19 deletion(19DEL) and exon 21 Leu858Arg(L858R) mutation types in lung adenocarcinoma(LUAD).

Methods: We analyzed the relationship between the expression of eHSP90α and clinicopathological features in 89 patients with L858R mutation and 196 patients with 19DEL mutation in LUAD.

View Article and Find Full Text PDF
Article Synopsis
  • Traditional cancer treatments face issues like toxicity, resistance, and high costs, prompting interest in bioactive phytochemicals that target multiple molecular pathways with less harm.
  • A network pharmacology approach was employed to analyze the active constituents for liver cancer treatment, utilizing databases for target retrieval and gene expression analysis.
  • Key survival-related genes (HSP90AA1, ESR1, CYP3A4, CDK1, MMP9) were identified, with four potent phytochemicals potentially influencing HSP90AA1 as a therapeutic target, supported by molecular dynamics simulation results showing stable interactions.
View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!