Heparin-induced bullous hemorrhagic dermatosis confined to the oral mucosa.

Unfractionated heparin (UFH) is frequently used in the treatment of venous thromboembolism and acute coronary syndrome. There are many common cutaneous adverse reactions to this medication. We present a unique case of hemorrhagic bullae limited to the oral mucosa that developed within 6 hours of a patient receiving UFH.

Impaired dopamine release and uptake in R6/1 Huntington's disease model mice.

Huntington's disease (HD) is a progressive, neurodegenerative movement disorder. Here, we used fast-scan cyclic voltammetry to measure dopamine release and uptake in striatal brain slices from R6/1 HD model mice. Peak dopamine release ([DA](max)) was significantly diminished in R6/1 mice (52% of wild-type at 24 weeks of age). Similarly, dopamine released per locally applied electrical stimulus pulse ([DA](p)), which is [DA](max) corrected for uptake and electrode performance, was also diminished in R6/1 mice (43% of wild-type by 24 weeks of age). Moreover, V(max), the maximum rate of dopamine uptake, obtained by modeling the stimulated release plots, was decreased at 16 and 24 weeks of age in R6/1 mice (51 and 48% of wild-type, respectively). Thus, impairments in both dopamine release and uptake appear to progress in an age-dependent manner in R6/1 mice.

Dysregulation of intracellular dopamine stores revealed in the R6/2 mouse striatum.

Huntington's disease (HD) is a fatal, neurodegenerative movement disorder characterized by preferential and extensive striatal degeneration. Here, we used fast-scan cyclic voltammetry to study the mobilization and efflux of reserve pool dopamine (DA) in striatal brain slices from HD model R6/2 mice. When applying stimulus trains of 120 pulses, evoked DA release in wild-type (WT) slices was greater than that in R6/2 slices at the higher frequencies (50 and 60 Hz). To quantify cytosolic and reserve pool DA levels, amphetamine-induced DA efflux was measured after pre-treatment with either tetrabenazine or alpha-methyl-p-tyrosine. Slices from 12-week-old R6/2 mice released less DA than slices from WT mice, while no difference was noted in slices from 6-week old mice. The vesicular release of reserve pool DA, mobilized by treatment with cocaine, was shorter lived in R6/2 slices compared with WT slices even though peak DA release was the same. Moreover, the number of DA reserve pool vesicles in R6/2 mice was less than half of that in WT. Therefore, our data suggest that the same number of DA molecules are present in each reserve pool vesicle in WT and R6/2 mice and that these vesicles are readily mobilized in both genotypes; however, R6/2 mice have fewer DA reserve pool vesicles available for mobilization.