Journal of Neuroscience, Vol 10, 734-740, Copyright © 1990 by Society for Neuroscience
Patterns of cell and fiber vulnerability in the mesostriatal system of the mutant mouse weaver. II. High affinity uptake sites for dopamine
S Roffler-Tarlov, D Pugatch and AM Graybiel
Program in Neurosciences, Tufts University School of Medicine, Boston, Massachusetts 02111.
Weaver (gene symbol wv) is an autosomal recessive mutation in the mouse
that causes the death of neurons in the cerebellum and of dopamine-
containing neurons in the mid-brain. In the accompanying paper and in
previous reports, the selective nature of the deficit produced by the gene
in the dopamine-containing systems has been described after analysis of the
patterns of the residual innervation in the striatum and the patterns of
cell death in the midbrain. In the present report, we describe deficits in
the terminals of the mesostriatal system occurring prior to a detectable
dopamine deficiency in the striatum and prior to the onset of cell death in
the mesencephalic dopamine- containing neurons during development. We have
also found deficits in the remaining terminals of the adult weaver's
striatum after the weaver pattern of innervation has been permanently
established. Axonal terminals in the caudoputamen are impaired in weaver
mice at postnatal day 7, before the onset of dopamine depletion in the
caudoputamen and cell death in the midbrain. The impairment was revealed by
a markedly deficient high-affinity uptake for 3H-dopamine by synaptosomes
prepared from the caudoputamen. Throughout the remainder of development and
in adulthood, the extent of the deficit in 3H-dopamine uptake was always
greater than that for dopamine content. No striatal region was completely
spared the effects of the gene. In the nucleus accumbens of the weavers,
where dopamine content is normal, 3H-dopamine uptake was reduced by 35% in
the synaptosomal preparations. In the olfactory tubercle, dopamine levels
were reduced by 44% but 3H-dopamine uptake was reduced by 60%.(ABSTRACT
TRUNCATED AT 250 WORDS)