ISSN:
1471-4159
Source:
Blackwell Publishing Journal Backfiles 1879-2005
Topics:
Medicine
Notes:
Abstract: The rat ventral tegmentum (containing somata and dendrites of mesolimbic dopaminergic neurones) contained 1.3 μmnol/g wet weight of glycine. Slices of ventral tegmentum accumulated exogenous [3H]glycine by an energy-, temperature- and sodium-dependent mechanism. The uptake was mediated by two different transport systems; one system with relatively low affinity for glycine (Km∼400 μm) and the other a higher affinity for glycine (Km∼ 10 μm). Small amino acid analogues of glycine inhibited the uptake process, the most potent being taurine and β-alanine (47% and 44% inhibition, respectively, at 1 mm). Release of exogenous [3H]glycine by elevated potassium and by protoveratrine A was calcium-dependent and tetrodotoxin-sensitive. Glycine (500 μm-2 mm) potentiated the protoveratrine A-induced release of exogenous [3H]dopamine from slices of ventral tegmentum; this potentiation was blocked by strychnine (10 μm). A convulsant dose of strychnine elevated the concentration of 3,4-dihydroxyphenylacetic acid in the ventral tegmentum. Glycine is likely to be a transmitter in the ventral tegmentum and to have a role regulating the activity of somatodendritic regions of mesolimbic dopaminergic neurones.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1111/j.1471-4159.1982.tb08665.x
