Central vasopressin and oxytocin receptor distributions in two species of singing mice

Abstract

The neuropeptides arginine vasopressin (AVP) and oxytocin (OT) are key modulators of vertebrate sociality. Although some general behavioral functions of AVP and OT are broadly conserved, the detailed consequences of peptide release seem to be regulated by species-specific patterns of receptor distribution. We used autoradiography to characterize central vasopressin 1a receptor (V1aR) and OT receptor (OTR) distributions in two species of singing mice, ecologically specialized Central American rodents with a highly developed form of vocal communication. While both species exhibited high V1aR binding in the auditory thalamus (medial geniculate), binding in structures involved in vocal production (periaqueductal gray and anterior hypothalamus) was significantly higher in the more vocal species, Scotinomys teguina. In S. xerampelinus, receptor binding was significantly higher in a suite of interconnected structures implicated in social and spatial memory, including OTR in the hippocampus and medial amygdala, and V1aR in the anterior and laterodorsal thalamus. This pattern is concordant with species differences in population density and social spacing, which should favor enhanced sociospatial memory in S. xerampelinus. We propose that V1aR and OTR distributions in singing mice support an integral role for the AVP/OT system in several aspects of sociality, including vocal communication and sociospatial memory.

Chronic methamphetamine treatment induces oxytocin receptor up-regulation in the amygdala and hypothalamus via an adenosine A2A receptor-independent mechanism

“…For instance, an upregulation of opioid receptors has been observed in preproenkephalin and preprodynorphin KO mice (Clarke et al , 2003). In the case of A 2A KO, we showed no compensatory changes in D 2 R, MOPr, DOPr, KOPr, 42 and 7 nAChR binding (Bailey et al, 2004a, Bailey et al, 2002a, Campbell et al, 2009. No change in OTR was also observed in saline-treated A 2A…”

Distribution of oxytocin and co-localization with arginine vasopressin in the brain of mice

“…The available, low-resolution maps of OT receptor binding in the brain of mice (Mus musculus) do not give enough detail on the distribution of OTR in the ventral striatum (Insel et al 1993;Hammock and Levitt 2013). However, this issue has been studied in other rodents, such as the singing mice of the species Scotinomys teguina and S. xerampelinus (Campbell et al 2009) and the rat (Veinante and Freund-Mercier 1997). Both studies coincide in showing relatively low density of OT binding in the Acb core, but higher density of OTR in the Acb shell.…”

Assembling the Puzzle: Pathways of Oxytocin Signaling in the Brain

“…It has been proposed that OT provides salience to sensory inputs by the gating of attention toward sensory stimuli linked to social clues. In songbirds, OTR are expressed in the pallium avian social behavior network and in most of the Central Oxytocin Pathways motor nuclei of the cranial nerves, suggesting a role in the efferent pathways of the vocal response (32,33). Expression in the motor nuclei of cranial nerves is also found in rodents (in particular in the X and XIII) (34) and marmosets (V and X) (35), indicating a shared capability of OT to directly and rapidly influence some motor and autonomic responses to social stimuli.…”