No abstract

The electrolysis rate and the separation factor for hydrogen isotopes are measured using the electrolysis cell having the hydrogen permeable cathode. As the hydrogen gas without the vapor of electrolyte is obtained by this method, decrease of the apparent separation factor by mixing with vapor can be avoided. I t is also observed in this study that enrichment and volume reduction of tritiated water using the bipolar electrode electrolysis cell is effective because it gives small loss of tritium from the cell during volume reduction. The separation factor obtained in this study indicates that attachment of two or three sub-cells is enough for volume reduction of tritiated water.

No abstract

Pain transmission in the spinal dorsal horn (SDH) is regulated by descending neuronal pathways from the brain, such as noradrenergic (NAergic) neurons from the locus coeruleus. While it is known that spinal NA produces an antinociceptive effect, we have recently shown that NA has an ability to produce pain hypersensitivity via Hes5expressing SDH astrocytes. However, the mechanism underlying the bidirectional effect of spinal NA remains unknown. In this study, we showed that while intrathecal injection of NA at a low dose (NA low ) induced pain hypersensitivity via α 1A -adrenergic receptors (α 1A -ARs) in Hes5 + astrocytes, the hypersensitivity was not observed by intrathecal high-dose NA (NA high ). The effect of NA high was also mediated by activation of inhibitory interneurons via α 1A -ARs. We found that NA high also activated β 1 -ARs in astrocytes that suppressed the astrocytic α 1A -ARs-mediated effect. However, if α 1A -ARs are expressed in inhibitory interneurons, why does NA low produce pain hypersensitivity?We further found that activation of astrocytic α 1A -ARs increased release of adenosine, a factor that suppresses inhibitory interneurons. Therefore, our findings indicate that NA bidirectionally modulates pain transmission via astrocyte-neuron interactions in a concentration-dependent manner.