The Journal of Neuroscience, December 1, 2002, 22(23):10078-10082
BRIEF COMMUNICATION
Defining the Caudal Ventral Striatum in Primates: Cellular and
Histochemical Features
Julie L.
Fudge1, 2 and
Suzanne N.
Haber2
Departments of 1 Psychiatry, 2 Neurobiology
and Anatomy, and 3 Neurology, University of Rochester
Medical Center, Rochester, New York 14642
Afferents from the amygdala help to define the ventral striatum and
mediate goal-directed behaviors. In addition to well known inputs to
the classic ventral striatum, the amygdala also projects to the
caudoventral striatum and amygdalostriatal area. We examined whether
the primate caudoventral striatum and amygdalostriatal area can be
considered part of the "ventral" striatum based on cellular and
histochemical features found in the classic rostral ventral striatum.
We used several histochemical stains, including calbindin-D28k, a
marker of the shell compartment, acetylcholinesterase, substance P,
tyrosine hydroxylase, and Bcl-2, a marker of immature neurons, to
examine this question. Our results indicate that the lateral
amygdalostriatal area and caudoventral striatum are "striatal like"
based on intermediate to high acetylcholinesterase and tyrosine hydroxylase levels. The lateral amygdalostriatal area is chemically similar to the shell, whereas the caudoventral striatum more closely resembles the striatum outside the shell. In contrast, the medial amygdalostriatal area is more related to the central amygdaloid nucleus
than to the striatum. Bcl-2 immunoreactivity is associated with
granular islands and medium-sized cells in the vicinity of the ventral
striatum both rostrally and caudally. Together, the caudal
ventral striatum has a histochemical and cellular organization similar to that of the rostral ventral striatum, consistent with their
common innervation by the amygdala and other ventral structures. In
addition, Bcl-2 is expressed in and near both poles of the ventral
striatum, suggesting that these areas maintain a heightened capacity
for growth and plasticity compared with other striatal sectors.
Key words:
amygdala; amygdalostriatal area; Bcl-2; islands of
Calleja; stria terminalis; ventral striatum
Copyright © 2002 Society for Neuroscience 0270-6474/02/222310078-05$05.00/0