Cellular localization of vasopressin V1a receptor messenger ribonucleic acid in adult male rat brain, pineal, and brain vasculature.

Abstract

Vasopressin V1a receptor (V1aR) transcripts were localized in brain, pineal, and superficial brain vascular tissues of adult male rats using hybridization histochemistry and an [35S]riboprobe complementary to the messenger ribonucleic acid (mRNA) encoding the fifth to the midseventh transmembrane regions of the receptor. V1aR mRNA was extensively distributed throughout brain and was expressed in 1) superficial cells of the granule cell layers of the main olfactory bulb, hippocampal dentate gyrus, and cerebellum; 2) numerous anatomically distinct brain nuclei; 3) isolated cells dispersed throughout the central nervous system; 4) cells of the choroid plexus, occasional blood vessels in the olfactory bulb and interpeduncular nucleus, and extraparenchymal intracranial vasculature; and 5) some white matter structures. Numerous cells expressing V1aR transcripts were found in forebrain structures, including primary olfactory (piriform) cortex, the anterior and posterior olfactory nuclei; dorsal, intermediate, and ventral lateral septal nuclei; the septo-fimbrial nucleus and accumbens nucleus; and numerous hypothalamic regions with the most intense hypothalamic labeling in the arcuate, stigmoid, suprachiasmatic, and periventricular nuclei and the lateral hypothalamic area. Cells expressing V1aR transcripts were ubiquitous throughout the midbrain, pontine, and medullary regions. A lower intensity signal was found in cells of the parvocellular paraventricular and anteroventral nucleus of the thalamus, circumventricular organs including the pineal, and the subfornical organ. V1aR transcripts were not generally detected in parenchymal vasculature, but could be found over large blood vessels in the interpeduncular nucleus and medial olfactory bulb; transcripts were commonly detected in perivascular brain cells. V1aR mRNA was abundantly expressed by choroid plexus, endothelial cells of midline blood vessels between the main olfactory bulbs, and superficial vascular tissue on all brain surfaces. These data confirm the presence of the vascular/hepatic-type V1aR gene in brain tissue and document an extensive expression. The distribution of V1aR mRNA suggests that there are at least two types of vasopressin-responsive cells in brain: one type exemplified by lateral septal ara neurons innervated by classical axodendritic/somatic synaptic vasopressinergic terminals and a second, perivascular/vascular type that would facilitate humoral vasopressinergic signaling in the brain.

Hyponatremia in cirrhosis: From pathogenesis to treatment†

“…It is, however, not known whether V 1a brain receptors respond to VP released within the brain itself or whether the receptors also respond to VP from the peripheral circulation. 67 V 1b (or V 3 ) receptors are not only expressed in the anterior pituitary 61 and kidney 62 as originally reported, but in a number of tissues, such as brain, uterus, thymus, heart, breast, and lung. 63 The physiological role of these extrapituitary V 1b receptors remains unknown, but some functions of VP attributed in the past to V 1a receptors or oxytocin receptors may be caused by the activation of V 1b receptors.…”

“…66 VP V 1a receptor mRNA was found to be extensively distributed throughout the brain, in which VP may act as a neurotransmitter or neuromodulator in addition to its classical role on vascular tone. 67 Specifically, brain VP receptors have been proposed to mediate the effect of VP on memory and learning, antipyresis, brain development, selective aggression, and partner preference in rodents, cardiovascular responsivity, blood flow to the choroid plexus and cerebrospinal fluid production, regulation of smooth muscle tone in superficial brain vasculature, and analgesia. It is, however, not known whether V 1a brain receptors respond to VP released within the brain itself or whether the receptors also respond to VP from the peripheral circulation.…”

Vasopressin V1b receptor knockout reduces aggressive behavior in male mice

“…[37][38][39][40][41] Chemosensory cues are transmitted from the main olfactory epithelium and volmeronasal epithelium to neurons in these brain regions where they are processed so that the appropriate behavioral response can be determined. [37][38][39][40][41] The MA and BNST both contain VP immunoreactivity [42][43][44] and V1aR binding and transcripts, [45][46][47] and V1bR immunoreactivity. 33 Aggressive behavior is correlated with VP immunoreactivity in fibers in the lateral septum (whose VP cell bodies are located in the BNST).…”

Distribution of AVP and Ca2+-dependent PKC-isozymes in the suprachiasmatic nucleus of the mouse and rabbit

“…AVP-induced responses of SCN cells in slices of the hamster hypothalamus and mediated by Vla receptors [20]. Vla receptors and transcripts have been demonstrated in the SCN by receptor autoradiography and in situ hybridization, respectively [18,32,33,46,53]. Stimulation of Via receptors results in phosphoinositol turnover and the subsequent activation of protein kinase C (PKC) [38,43].…”