Kaoru Kondo

Ruthenium catalyzed synthesis of secondary or tertiary amines from amines and alcohols

Abstract Unsymmetrical secondary and tertiary amines are prepared by the ruthenium catalyzed reaction of alcohols with amines, which provides highly efficient method for synthesis of cyclic amines.

Expression of glutamate transporters in cultured glial cells

Expression of mRNAs for glutamate transporter (GLT-1) and glutamate aspartate transporter (GLAST) was investigated in three different types of purified glial cells by the reverse transcriptase-polymerase chain reaction (RT-PCR). Cultured astrocytes, oligodendrocytes, and microglia expressed mRNAs for GLAST and GLT-1; mRNA for GLAST was expressed more prominently than that for GLT-1 in astrocytes. Oligodendrocytes and microglia expressed mRNAs for both GLT-1 and GLAST equally, but the expression in microglia was not prominent, suggesting glutamate uptake is not essential in microglia. In astrocytes cultured from different brain regions, GLAST mRNA was equally expressed. GLT-1 mRNA was also detected in these astrocytes, but the expression level was lower than that of GLAST.

Expression pattern of messenger RNAs for prostanoid receptors in glial cell cultures

Expression level of messenger RNAs (mRNAs) for prostanoid EP3, FP, and TP receptors was investigated in cultured rat astrocytes, oligodendrocytes, and microglia, as well as in meningeal fibroblasts, rat glioma C6 cells, rat pheochromocytoma PC12 cells, whole brain, and several peripheral tissues by reverse transcriptase-polymerase chain reaction. Cultured astrocytes and oligodendrocytes expressed mRNAs for 3 prostanoid receptors examined. In contrast, cultured microglia and pheochromocytoma PC12 cells expressed EP3 and TP receptor mRNAs, but not FP receptor mRNA. Glioma C6 cells expressed only TP receptor mRNA among 3 prostanoid receptors with the same expression level as that in astrocytes. Cultured meningeal fibroblasts expressed 3 receptor transcripts, and their expression levels were lower than those in astrocytes. Expression level of mRNA for each prostanoid receptor in cultured glial cells was higher than that in whole brain. These observations suggest that each prostanoid has its specific roles in each glial cell type of the brain.

Selective transformation of organoboranes to grignard reagents by using pentane-1,5-di(magnesium bromide). Syntheses of the pheromones of southern armyworm moth and Douglas fir tussock moth

Abstract The selective transformation of trialkylboranes or B-alkyl-9-borabicyclo[3.3.1]-nonanes to alkylmagnesium bromides was accomplished upon treatment with pentane-1,5-di(magnesium bromide) ( 1 ) in benzene.

Desensitization of prostaglandin F2α receptor-mediated phosphoinositide hydrolysis in cultured rat astrocytes

Desensitization of prostaglandin (PG) F2α receptor-mediated phosphoinositide (PI) hydrolysis was investigated in cultured rat astrocytes. Prolonged exposure of astrocytes differentiated by dibutyryl cyclic AMP-treatment to PGF2α caused the desensitization of subsequent PGF2α-induced PI hydrolysis. The desensitization was time- and PGF2α dose-dependent; maximal decrease in the PI hydrolysis was observed after exposure to 10 μM PGF2α for 4 h and the degree of the desensitization was 31.7±2.7% of control. Pretreatment with either PGD2 or PGE2 also induced the desensitization of subsequent PGF2α-stimulated PI hydrolysis and conversely pretreatment of PGF2α decreased the PI responses to PGD2 and PGE2. The desensitization prevented by phloretin and was reversible upon removal of the agonist. Protein synthesis inhibitors blocked the recovery of the desensitization. Treatment of the cells with phorbol 12-myristate 13-acetate had no effect on the desensitization. These results suggest that prolonged exposure of the astrocytes to PGF2α caused the desensitization of the receptors.