Fig. 21.
A: Color
micrograph illustrating ChAT labeled cell body in
the medial septum approximated by PHA-L labeled terminal varicosities (arrows)
following a PHA-L injection in the medial hypothalamus (case M078). B:
Several PHA-L labeled terminal varicosities (arrows) from a PHA-L labeled axon
are seen in close proximity to a distal cholinergic dendrite in the substantia
innominata following a PHA-L injection in the lateral hypothalamus (case
L125). C: PHA-L labeled terminal
varicosities are seen abutting proximal dendrites (arrows) of two ChAT labeled
neurons in the substantia innominata following a tracer injection in the
lateral hypothalamus (case L123). The terminal varicosities shown are from the
same axon (arrowhead). D: PHA-L labeled terminal varicosities in
proximity to a proximal dendrite of ChAT labeled cell in the dorsal HDB from
case L123. The grid simulates the
proportions of the ocular reticle used to screen sections from high
magnification light microscopic analysis. Scale bar (A-D): 16 μm (one division of grid in D). E-G:
Composite maps illustrating putative zones of contact between afferent fibers
and cholinergic neuronal elements following PHA-L injections into the (E)
far-lateral hypothalamus (case L125), (F) mid-lateral hypothalamus (case L123),
and (G) medial hypothalamus (case
M067). These maps were composed from 8
camera lucida drawings which were aligned and superimposed to generate the
final figure. Cholinergic neurons are
represented by black dots. Zones of
putative contacts between cholinergic elements and PHA-L labeled terminals are
depicted as red squares (corresponding to 80x80 µm areas in the section).