ISSN:
1471-4159
Source:
Blackwell Publishing Journal Backfiles 1879-2005
Topics:
Medicine
Notes:
Abstract: 3,4-Dihydroxyphenylethylamine (DA, dopamine) levels in the rat prefrontal cortex were selectively decreased by 52%, leaving noradrenaline (NA) levels unaffected, 4 weeks following restricted bilateral electrolytic lesions of the ventral mesencephalic tegmentum (VMT). These lesions also induced a significant increase in DA-sensitive, but not isoproterenol-sensitive, adenylate cyclase activity in tissue homogenates (+ 38%). We had shown previously that chemical (6-hydroxydo-pamine, 6-OHDA) lesions of the VMT destroy both ascending DA and NA fibers but do not alter the D1-receptor density in the prefrontal cortex. In this study, electrolytic lesions of the VMT were combined with bilateral injections of 6-OHDA made laterally in the pedunculus cerebellaris superior to assess the role of NA fibers in the development of D1-receptor supersensitivity. This combined treatment produces a large decrease of cortical NA levels (-95%), an increase in β-adrenergic-sensitive adenylate cyclase activity (+110%), and a decrease in DA levels (- 60%), but does not alter D1-receptor density in the prefrontal cortex. These results indicate that the development of D1-receptor supersensitivity in the prefrontal cortex following electrolytic lesion of the VMT depends on the presence of an intact NA innervation.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1111/j.1471-4159.1986.tb12953.x
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