Vasopressin in the brain of a desert hibernator, the jerboa (Jaculus orientalis): Presence of sexual dimorphism and seasonal variation

Abstract

The distribution of vasopressin innervation in the brain of the jerboa (Jaculus orientalis) was investigated, with special attention to sex differences and seasonal variations. Vasopressin perikarya were observed in the paraventricular and supraoptic nuclei, the suprachiasmatic nucleus, the periventricular nucleus, the medial preoptic area, the bed nucleus of the stria terminalis, and the medial amygdaloid nucleus. In addition, vasopressin cell bodies were observed in the ventral retrochiasmatic area. After treatment with colchicine, vasopressin perikarya were also observed around the organum vasculosum laminae terminalis, in the medial diagonal band of Broca, and in the dorsal medial preoptic nucleus. Vasopressin fibers were also found to be more widespread in the jerboa brain than in other rodents. Fibers were observed in the medial diagonal band of Broca, the stria medullaris, the tuber cinerum, the area postrema, the medial vestibular nucleus, and the dorsal motor nucleus of the vagus. Sexual dimorphism and seasonal variation in vasopressin immunoreactivity were observed in areas that not only showed a testosterone-dependent vasopressin innervation in other rodents but also in the paratenial and mediodorsal thalamic nuclei, the tuber cinerum, the supramammillary complex, the zona incerta, the interpeduncular complex, and the dorsal and medial raphe nuclei. A denser vasopressin innervation was observed in spring/summer (sexual active period) than in autumn. Numerous brain structures contained vasopressin receptors (cerebral cortex, hypothalamus, substantia nigra, dentate gyrus, thalamic nuclei, superior colliculus, dorsal cochlear nucleus, and cerebellum); no sex- or season-related differences were observed. These data indicate a high level of vasopressin in the jerboa brain, which may reflect an adaptation to its harsh bioclimatic environment.

Distribution of vasopressin in the brain of the eusocial naked mole‐rat

“…The hypothalamo-hypophyseal VP-ir system in naked mole-rats is very similar to that reported in other rodent species (De Vries et al, 1985;Dubois-Dauphin et al, 1989;Ferris et al, 1992;Lakhdar-Ghazal et al, 1995). Magnocellular VP-ir cells were found in the PVN (Figs.…”

Seasonal Variation in Group Size Is Related to Seasonal Variation in Neuropeptide Receptor Density

“…The most striking examples of seasonal plasticity in neurochemical systems come from animals caught directly from the field [Lakhdarghazal et al, 1995;Goodson et al, 2012b]. These, along with our data, suggest that the exposure to a full range of environmental and social stimuli is necessary to reveal the natural extent of seasonal plasticity in neurochemical systems.…”

Cryptic Regulation of Vasotocin Neuronal Activity but Not Anatomy by Sex Steroids and Social Stimuli in Opportunistic Desert Finches

“…In this respect the zebra finch is very different from laboratory rats and mice [De Vries et al, 1984, 1986Miller et al, 1989;Scordalakes and Rissman, 2004] and species that exhibit seasonal patterns of breeding Voorhuis et al, 1988;Crenshaw et al, 1992;Viglietti-Panzica et al, 1992;Wang and De Vries, 1993;reviews: Boyd, 1994;Dubois-Dauphin et al, 1994;Lakhdar-Ghazal et al, 1995;Goodson and Bass, 2001;Plumari et al, 2004;De Vries and Panzica, 2006;Kabelik et al, 2008]. Despite this anatomical stability, however, the VT system of zebra finches is influenced somewhat cryptically by both social and hormonal variables, such that housing subjects in mixed-sex cages with nests increases Fos immunoreactivity within VT-ir neurons of the BSTm, whereas manipulations that block androgenic steroid circuits decrease VT-Fos colocalization.…”

“…forebrain, particularly the lateral septum (LS) Voorhuis et al, 1988;Crenshaw et al, 1992;Viglietti-Panzica et al, 1992;Wang and De Vries, 1993;reviews: De Vries and Panzica, 2006;Goodson, 2008;Boyd, 1994;Dubois-Dauphin et al, 1994;Lakhdar-Ghazal et al, 1995;Plumari et al, 2004;Kabelik et al, 2008]. Levels of VT and its mammalian homologue VP are highly dependent on circulating steroid hormone levels and thus often vary with hormonal changes across breeding season and photoperiod [e.g., Moore et al, 2000;Kabelik et al, 2008;Rasri et al, 2008;reviews: De Vries and Boyle, 1998;Goodson and Bass, 2001].…”