Cholinergic profiles in the Goettingen miniature pig (Sus scrofa domesticus) brain

Abstract

Central cholinergic structures within the brain of the even-toed hoofed Goettingen miniature domestic pig (Sus scrofa domesticus) were evaluated by immunohistochemical visualization of choline acetyltransferase (ChAT) and the low-affinity neurotrophin receptor, p75NTR. ChAT immunoreactive (-ir) perikarya were seen in the olfactory tubercle, striatum, medial septal nucleus, vertical and horizontal limbs of the diagonal band of Broca and the nucleus basalis of Meynert, medial habenular nucleus, zona incerta, neurosecretory arcuate nucleus, cranial motor nuclei III and IV, Edinger-Westphal nucleus, parabigeminal nucleus, pedunculopontine nucleus and laterodorsal tegmental nucleus. Cholinergic ChAT-ir neurons were also found within transitional cortical areas (insular, cingulate, and piriform cortices) and hippocampus proper. ChAT-ir fibers were seen throughout the dentate gyrus and hippocampus, in the mediodorsal, laterodorsal, anteroventral and parateanial thalamic nuclei, the fasciculus retroflexus of Meynert, basolateral and basomedial amygdaloid nuclei, anterior pretectal and interpeduncular nuclei, as well as select laminae of the superior colliculus. Double immunofluorescence demonstrated that virtually all ChAT-ir basal forebrain neurons were also p75NTR positive. The present findings indicate that the central cholinergic system in the miniature pig is similar to other mammalian species. Therefore, the miniature pig may be an appropriate animal model for preclinical studies of neurodegenerative diseases where the cholinergic system is compromised.

A Preliminary Description of the Sleep‐Related Neural Systems in the Brain of the Blue Wildebeest, Connochaetes taurinus

“…The current study, to the authors' knowledge, is the first to provide a detailed qualitative and partial quantitative description of the sleep–wake‐related nuclei in the brain of the blue wildebeest, C. taurinus . In the brain of the blue wildebeest, from the basal forebrain to the pons, the nuclear organization of the cholinergic, catecholaminergic, serotonergic, and orexinergic systems for the most part, showed a corresponding nuclear organization to that reported in other mammals and more specifically the Cetartiodactyla (Manger et al, ; Bhagwandin et al, ; Gravett et al, ; Bux et al, ; Dell et al, ,b,c; Mahady et al, , Davimes et al, ). Furthermore, the description and distribution of the GABAergic system, which was examined through immunostaining for the calcium binding proteins CB, CR, and PV, was also similar to that seen in other mammals (Bhagwandin et al, ; Dell et al, ,b,c; Davimes et al, ).…”

“…The cholinergic nuclei located in the basal forebrain and pons of the blue wildebeest shared a similar location and nuclear organization as that found in all other mammals studied to date (e.g., Maseko et al, ; Gravett et al, ; Bux et al, ; Dell et al, , ,b,c). In the giraffe and river hippopotamus it was noted that the somata of the cholinergic LDT neurons were larger than those of the cholinergic PPT neurons (Bux et al, ; Dell et al, ), in cetaceans no difference in somal size was noted (Dell et al, ,b), but for the Goettingen mini‐pig, Arabian oryx and blue wildebeest, the soma of the LDT neurons were smaller than those of the PPT neurons (Mahady et al, ; Davimes et al, ). Thus, while the nuclear organization and topology of the cholinergic neurons involved in the sleep–wake cycle are consistent across Cetartiodactyla, and mammals more generally, there are variances that may influence the expression of sleep and global brain states across species.…”

“…To date, only a few neuroanatomical studies have been conducted on the neural systems involved in the generation, maintenance, and modulation of sleep in the order Cetartiodactyla (Tillet and Thibault, ; Østergaard et al, ; Kitahama et al, ; Tillet, ; Leshin et al, ,b, ; Tillet and Kitahama, ; Ferreira et al, ; Iqbal et al, ; Bux et al, ; Ettrup et al, ; Dell et al, , ,b,c; Mahady et al, ; Davimes et al, ). Although these studies have revealed that the neural systems involved in sleep are, for the most part, typically mammalian, certain Cetartiodactyl specific features have been observed (Manger, ).…”

“…Although these studies have revealed that the neural systems involved in sleep are, for the most part, typically mammalian, certain Cetartiodactyl specific features have been observed (Manger, ). The neurons of the cholinergic laterodorsal tegmental (LDT) nucleus are larger than those of the pedunculopontine tegmental (PPT) nucleus in the giraffe (Bux et al, ) and the river hippopotamus (Dell et al, ), but they were similar in size in the harbor porpoise and minke whale (Dell et al, ,b), whereas the converse was true for the Göttingen minipig (Mahady et al, ) and the Arabian oryx (Davimes et al, ). The orexinergic neurons of the Cetartiodactyl hypothalamus exhibit a medially located parvocellular cluster not observed in most other mammals (except African elephant, Maseko et al, ), but that has been observed in the giraffe, harbor porpoise, minke whale, river hippopotamus, and Arabian oryx (Dell et al, , ,c; Davimes et al, ).…”

The cholinergic system in the basal forebrain of the Atlantic white‐sided dolphin (Lagenorhynchus acutus)

“…The basal forebrain (BFB) cholinergic system has been studied extensively in terrestrial mammals (Ferreira, Meurisse, Tillet, & Levy, ; Kimura, McGeer, Peng, & McGeer, ; Levey, Wainer, Mufson, & Mesulam, ; Mahady, Perez, Emerich, Wahlberg, & Mufson, ; Mesulam & Geula, ; Mesulam, Mufson, Levey, & Wainer, a; Mesulam, Mufson, Wainer, & Levey, 1984) due to its importance in behavior, attention, memory, and the sleep‐wake cycle (Anaclet et al, ; Atri et al, ; Ballinger, Ananth, Talmage, & Role, ; Baxter & Chiba, ; Brown, Basheer, McKenna, Strecker, & McCarley, ; Croxson, Kyriazis, & Baxter, ; Drachman & Leavitt, ; Everitt & Robbins, ; Mesulam, ). The number of studies describing the cholinergic BFB in cetaceans are limited (Dell et al, , ) and not available in delphinid species.…”