Does d-serine in the midbrain periaqueductal gray contribute to morphine tolerance in rats?
Our data indicate that the development of antinociceptive tolerance to morphine is partially mediated by ventrolateral midbrain periaqueductal gray D-serine content, and the activation of the ventrolateral midbrain periaqueductal gray P2X7 receptor is an essential prelude to D-serine release. These results suggest that a cascade involving P2X7 receptor-D-serine-N-methyl-D-aspartate receptor mediated signaling pathway in the supraspinal mechanism of morphine tolerance.
Using a novel ex vivo model, human LC are shown for the first time to be the major epidermal cell type that is involved in transmission of HIV infection to human lymphoid tissue. Importantly, this system could prove useful in further understanding LC trafficking and other early biological events involved in primary HIV infection.