Neuropeptide Y-Like Immunoreactivity in Area 17 of Chimpanzee

Abstract

Summary: The distribution and morphology of neuropeptide Y-like immunoreactive (NPY+) neurons in area 17 were studied in 4 chimpanzees (15 to 56 years old) with the aid of immunocytochemical methods. The NPY+ neurons were not pyramidal, but were either multipolar, bipolar, or bitufted in shape. They occurred most frequently in layer 6 and the subjacent white matter, they were sparser in the supragranular layers, and were few in layer 4. The NPY+ somata in the supragranular layers were significantly smaller than those in the infragranular layers. The axon of NPY cells originated either from the soma or from the primary dendrite. The distribution and morphology of NPY+ neurons were not different between the youngest and the oldest chimpanzee. The oval shape of NPY+ neurons, however, changed slightly with aging to a more circular shape. The density of NPY+ fibers was laminar-dependent. A distinct plexus extended through the upper part of layer 4 and the lowest aspect of layer 3. A thin fiber band was found in the lowest part of layer 4. Some NPY+ axons vertically traversed the cortex between pia and white matter. In the superficial layers, "snarls" of fibers appeared

Neuropeptide Y‐immunoreactive Neurons in the Cerebral Cortex of Humans and Other Haplorrhine Primates

“…and ). The morphological cell types and distributions were in general accordance with previous results in macaque [Hendry et al, ; Kuljis and Rakic, ; Zaitsev et al, ], chimpanzee [Mori, ], and human [Delalle et al, ; Kowall and Beal, ; Suarez‐Sola et al, ], with bipolar and multipolar interneuron subtypes represented in all species (Fig. ).…”

“…The sections were then incubated in an avidin‐peroxidase complex (PK‐6100, Vector Laboratories, Burlingame, CA, USA) followed by a 3, 3′‐diaminobenzidine‐peroxidase substrate with nickel enhancement (SK‐4100, Vector Laboratories). The pattern of NPY‐ir neurons and axons obtained using this primary antibody that was generated from the first residue of pig C‐terminus were in concordance with that previously described in humans [Kowall and Beal, ], chimpanzee [Mori, ], and macaque monkeys [Hendry et al, ; Kuljis and Rakic, , ].…”

“…Within the cerebral cortex, NPY is involved in synaptic transmission [Bacci et al, ], regulation of cerebral blood flow [Cauli et al, ; Estrada and DeFelipe, ; Hamel et al, ], and inhibition of neuronal excitability [Colmers and Bleakman, ]. NPY cortical neurons are mostly GABAergic [Hendry et al, ] and morphologically they appear as bipolar, bitufted, and multipolar types [Hendry et al, ; Kuljis and Rakic, ; Mori, ]. These neurons are distributed throughout the layers of the neocortex, but are most numerous in layers II‐III and VI [Hendry et al, ; Kubota et al, ; Kuljis and Rakic, ].…”

Populations of subplate and interstitial neurons in fetal and adult human telencephalon

“…In the monkey, subplate and interstitial neurons also contain a variety of neuropeptides, i.e. neuropeptide Y (Huntley et al 1988;Hayashi et al 1989;Kuljis & Rakic, 1989;Mori, 1996), cholecystokinin , somatostatin (Huntley et al 1988;Yamashita et al 1989;Iritani & Satoh, 1991), substance P (Yamashita et al 1990;Mehra & Hendrickson, 1993) and vasoactive intestinal polypeptide (Benson et al 1991). Finally, at least some human subplate and interstitial neurons also contain calcium-binding proteins, such as calbindin (Yan et al 1996b;Ulfig, 2002;Suá rez-Solá et al 2009) and calretinin (Gabbott et al 1997;Ulfig, 2002;Suá rez-Solá et al 2009).…”