Primates cholinergic neurons

Nerve growth factor (NGF) (Levi-Montalcini and Angeletti, 1968), is a well established trophic factor for the cholinergic neurons of the basal forebrain (Hefti, 1986 Williams et al., 1986). Moreover, in aged rodents and primates that have been demonstrated to be deficient in cortical ACh signaling, NGF has been shown both to increase ACh synthesis and improve memory deficits (Haroutunian... 

Tuszynski, M. H. et al. (1991). Recombinant human nerve growth factor infusions prevent cholinergic neuronal degeneration in the adult primate brain. Ann. Neurol. 30(5), 625-636. 

Price DL, Whitehouse PJ, Struble RG, Price DL, Cork IC, Hedreen JC, Kitt CA (1983) Basal forebrain cholinergic neurons and neuritic plaques in primate brain. In Katzman R (ed), Biological aspects of Alzheimer s disease. Cold Spring Harbor Laboratory, Cold Spring Harbor, New York, p 65... 

In both the nonhuman primates and humans, D2 mRNA was found to be homogeneously distributed in the striosomal and matrix compartments of the caudate nucleus and putamen, with no medial to lateral gradient. At variance with D receptors, D2 receptors were also detected in large, putatively cholinergic neurons. In the ventral portion of the striatum, NAc and olfactory tubercle, D2 receptor mRNA distribution was sparser than in to the dorsal striatum, with islands of tightly packed small cells (Richfield et al., 1987 Huntley et al., 1992 Rappaport et al., 1993 Meador-Woodruff et al., 1996). 

Thus, no consensual conclusion is available about the behavioural and cognitive effects of basal forebrain cholinergic neuron lesions in nonhuman primates. However, one has to keep in mind that AD is not solely a disease of the cholinergic system. 

Tuszynski, M. H., U, H. S., Amaral, D. G., and Gage, F. H., Nerve growth factor infusion in the primate brain reduces lesion-induced cholinergic neuronal degeneration, J. Neurosci., 10, 3604, 1990. 

Implants of polymer-encapsulated human NGF-secreting cells in the nonhuman primate Rescue and sprouting of degenerating cholinergic basal forebrain neurons. Emerich, D.F., Winn, S.R., Harper, J., Hammang, J.P., Baetge, E.E., Kordower, J.H. (1994). J Comp Neurol, 349 (1) 148-164. 

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