N. Fujise et al., DISTRIBUTION OF THE CALCIUM-BINDING PROTEINS, CALBINDIN D-28K AND PARVALBUMIN, IN THE SUBICULAR COMPLEX OF THE ADULT-MOUSE, Neuroscience research, 22(1), 1995, pp. 89-107
The immunohistochemical localizations of two specific calcium binding
proteins, calbindin D-28K (calbindin) and parvalbumin (PV) were examin
ed in the subicular complex, that is, the subiculum, presubiculum, and
parasubiculum, of the adult mouse and were compared in detail with st
aining pattern of the acetylcholinesterase (AChE) histochemistry. The
calbindin immunoreactivity exhibited a conspicuous regional and lamina
r pattern of distribution, which somewhat resembled the AChE staining
pattern but was apparently different from the latter in various points
. The PV immunoreactivity also exhibited a characteristic regional dif
ference, although less prominent, The subiculum could be divided into
two subregions, intensely calbindin-immunoreactive (calbindin-IR) and
AChE stained proximal subiculum and only faintly calbindin-IR and AChE
stained distal subiculum. In the subiculum most of calbindin-IR neuro
ns were pyramidal cells which were clustered in the superficial half o
f the cell layer in the proximal subiculum and appeared to be segregat
ed from calbindin negative pyramidal cells located in the distal subic
ulum and in the basal part of the proximal subiculum. In the presubicu
lum calbindin-IR neurons were clustered in layer 2, most of which were
supposed to be presubicular pyramidal cells. In the parasubiculum, th
e overall immunostaining pattern of PV and calbindin were somewhat com
plementary, In the transition area calbindin-IR neurons were clustered
but few PV-IR neurons were located, and thus the distribution of immu
noreactive neuronal somata was apparently different from the adjacent
parts of the parasubiculum, indicating that the transition area might
be a separate entity. In addition to calbindin-IR presumable principal
neurons, calbindin-IR and PV-IR nonpyramidal cells were scattered thr
oughout the subicular complex, Furthermore, these two calcium binding
proteins were colocalized in some nonpyramidal cells in the subicular
complex. The present study revealed some new aspects of the areal and
laminar organization of the subicular complex, which had not been show
n by previous classical purely morphological approaches.