Distribution of oxytocin in the brain of a eusocial rodent

• Published in: Neuroscience Vol. 155; no. 3; pp. 809 - 817
• Main Authors: Rosen, G.J, de Vries, G.J, Goldman, S.L, Goldman, B.D, Forger, N.G
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 26.08.2008; Elsevier
• Subjects: Animals; Biological and medical sciences; Brain - anatomy & histology; Brain - metabolism; Brain Mapping; Fundamental and applied biological sciences. Psychology; Heterocephalus glaber; Mole Rats - anatomy & histology; Mole Rats - metabolism; naked mole-rat; Neurology; Oxytocin - metabolism; sex differences; social hierarchy; sociality; vasopressin; Vertebrates: nervous system and sense organs; dorsal lateral septum; normal goat serum; MeA; PVN; Oxt; PVNpm; locus coeruleus; MPO; parabrachial nucleus; PVT; Tris-buffered saline; Tris-buffered saline containing 0.03% Triton; Amb; nucleus ambiguus; BST; oxytocin; TBS; nucleus of the solitary tract; vasopressin; tenia tecta, dorsal part; ir; medial preoptic area; nucleus accumbens; paraventricular nucleus of the hypothalamus; reticular nucleus; Tris-Triton; VH; bed nucleus of the stria terminalis; ventral horn; ventral tegmental area; paraventricular nucleus of the thalamus; supraoptic nucleus; paraventricular nucleus of the hypothalamus, posterior magnocellular part; VP; NGS; LSd; RN; sociality; VTA; H; LPO; habenula; NTS; nucleus of the solitary tract, medial part; SI; medial nucleus of the amygdala; sex differences; ACB; substantia nigra; lateral preoptic area; NTSm; TTd; facial nucleus; substantia innominata; PB; naked mole-rat; SON; immunoreactive; SNr; LC; PAG; VII; social hierarchy; Heterocephalus glaber; periaqueductal gray; Oxytocin; Central nervous system; Rodentia; Sex; Neuropeptide; Vasopressin; Encephalon; Vertebrata; Mammalia; Distribution
• ISSN: 0306-4522; 1873-7544
• DOI: 10.1016/j.neuroscience.2008.05.039

Abstract Naked mole-rats are highly social rodents that live in large colonies characterized by a rigid social and reproductive hierarchy. Only one female, the queen, breeds. Most colony members are non-reproductive subordinates that work cooperatively to rear the young and maintain an underground burrow system. Little is known about the neurobiological basis of the complex sociality exhibited by this species. The neuropeptide oxytocin (Oxt) modulates social bonding and other social behaviors in many vertebrates. Here we examined the distribution of Oxt immunoreactivity in the brains of male and female naked mole-rats. As in other species, the majority of Oxt-immunoreactive (Oxt-ir) cells were found in the paraventricular and supraoptic nuclei, with additional labeled cells scattered throughout the preoptic and anterior hypothalamic areas. Oxt-ir fibers were found traveling toward and through the median eminence, as well as in the tenia tecta, septum, and nucleus of the diagonal band of Broca. A moderate network of fibers covered the bed nucleus of the stria terminalis and preoptic area, and a particularly dense fiber innervation of the nucleus accumbens and substantia innominata was observed. In the brainstem, Oxt-ir fibers were found in the periaqueductal gray, locus coeruleus, parabrachial nucleus, nucleus of the solitary tract, and nucleus ambiguus. The high levels of Oxt immunoreactivity in the nucleus accumbens and preoptic area are intriguing, given the link in other rodents between Oxt signaling in these regions and maternal behavior. Although only the queen gives birth or nurses pups in a naked mole-rat colony, most individuals actively participate in pup care.