Experimental demonstration of intrinsic synapses in cat's caudate nucleus

Quantitation of nerve terminal populations: Synaptic vesicle‐associated proteins as markers for synaptic density in the rat neostriatum

“…The results following kainic acid lesions strongly suggest that only about 35% of the nerve terminals in the neostriatum derive from intrinsic neurons. These results are in disagreement with the early suggestions (Kemp, 1968;Tennyson, 1975) that the majority of striatal nerve terminals originated inside the striatum, but support the semiquantitative estimate of almost 80% degenerating synaptic boutons which appeared following a complete deafferentation of the cat caudate nucleus (Hassler et al, 1977). Moreover, the majority of cells in the neostriatum appear to express the GABA marker GAD (Oertel and Mugnaini, 1984), either alone or in combination with different neuropeptides (Penny et al, 1986).…”

“…Previous work has indicated that the major input to the neostriatum derives from the cortex, followed by that from the thalamus, and, with very few fibers, that from the midbrain, and that all of these inputs terminate predominantly with asymmetric synapses on dendritic spines (Graybiel and Ragsdale, 1979;Heimer et al, 1985;Kemp, 1968;Nauta and Domesick, 1984). Estimates of the exact proportion of different nerve terminals belonging to distinct neuronal populations vary widely, however (Hassler et al, 1977(Hassler et al, , 1978Hattori et al, 1976Hattori et al, , 1979. Our results indicate that the corticostriatal fibers contribute 45-50% of the nerve terminals in the neostriatum, that the ascending striatopetal fibers contribute approximately 20%, and that the kainic acidsensitive neurons (presumably intrinsic cells in the neostriatum) contribute approximately 35% of the total number of nerve terminals in the striatum.…”

Ultrastructural evaluation of the damage of postsynaptic elements after kainic acid injection into the rat neostriatum

“…The observed intact axosomatic and axodendritic synapses with symmetric junctions may correspond to junctions of type V and IX from among the nine synapse types from the striatum [Hassler and Chung, 1976;Hassler et al, 1977;Chung, 19791. These synapses are probably formed by the plexus of intrinsic striatal neurons [Chung, 19791.…”

Striatal Synapses and Their Origin

“…1 h-j) [1, 2]; and inputs from axon terminals of intrinsic neurons contain synapses of type IX ( fig. Ik) [5]. Many of the type V synapses, which are probably formed by axon collaterals of the efferent neurons of the striatum, are preserved after surgical isolation of the head of the caudate nucleus f5J.…”