Shin-ichi Akanuma

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ATP-binding cassette transporter A1 (ABCA1) mediates apolipoprotein-dependent cholesterol release from cellular membranes. Recent studies using ABCA1 knockout mice have demonstrated that ABCA1 affects amyloid-beta peptide (A beta) levels in the brain and the production of senile plaque. Cerebral A beta(1-40) was eliminated from the brain to the circulating(More)
The aim of the present study was to investigate the expression of nuclear receptor mRNA and regulation of the expression of ATP-binding cassette (ABC) transporters by nuclear receptor agonists in rat brain capillary endothelial cells, which form the blood-brain barrier, by using rat brain capillary fraction from 8-week-old rats and a conditionally(More)
Although glycine plays a pivotal role in neurotransmission and neuromodulation in the retina and is present in high concentration in the retina, the source of retinal glycine is still unclear. The purpose of the present study was to investigate glycine transport across the inner blood-retinal barrier (inner BRB). [(14)C]Glycine transport at the inner BRB(More)
BACKGROUND Peripheral administration of lipopolysaccharide (LPS) induces inflammation and increases cerebral prostaglandin E2 (PGE2) concentration. PGE2 is eliminated from brain across the blood-brain barrier (BBB) in mice, and this process is inhibited by intracerebral or intravenous pre-administration of anti-inflammatory drugs and antibiotics such as(More)
D-Serine is a co-agonist for NMDA-type glutamate receptors. Although D-serine levels in CSF and interstitial fluid (ISF) affect CNS function, the regulatory system remains to be fully understood. Therefore, the purpose of this study was to investigate d-serine transport across the blood-brain barrier (BBB) and blood-CSF barrier (BCSFB) and in brain(More)
To clarify the transport and inhibition characteristics involved in verapamil transport across the inner blood-retinal barrier (inner BRB). The transport of [3H]verapamil across the inner BRB was investigated using retinal uptake index and integration plot analyses in rats. The detailed transport characteristics were studied using TR-iBRB2 cells, a(More)
Organic anion transporting polypeptide (Oatp) transporters at the blood–brain barrier (BBB) and the blood-retinal barrier (BRB), which consists of retinal capillary endothelial cells and retinal pigment epithelial cells, are major determinants of the control of anionic drugs into the brain and retina. Although Oatp1a4 (Slco1a4) and Oatp1c1 (Slco1c1) are(More)
In the retina, taurine works as an osmolyte to exert a neuroprotective function, and it has been proposed that Müller cells, a major type of retinal glial cells, are involved in the osmolarity regulation of retinal neural cells by controlling the taurine concentration in retinal extracellular fluid (ECF). However, the detailed mechanism of taurine transport(More)
Guanidinoacetic acid (GAA) is the biosynthetic precursor of creatine which is involved in storage and transmission of phosphate-bound energy. Hepatocytes readily convert GAA to creatine, raising the possibility that the active uptake of GAA by hepatocytes is a regulatory factor. The purpose of this study is to investigate and identify the transporter(More)
PURPOSE To elucidate the mechanism(s) of hypoxanthine production in Müller cells and the elimination of hypoxanthine across the inner blood-retinal barrier (BRB). METHODS The hypoxanthine biosynthesis and adenosine transport in Müller cells were investigated using a conditionally immortalized rat Müller cell line, TR-MUL5 cells. The elimination of(More)