The Experts below are selected from a list of 7326 Experts worldwide ranked by ideXlab platform
John Godwin - One of the best experts on this subject based on the ideXlab platform.
-
Sexual Phenotype Differences in zic2 mRNA Abundance in the Preoptic Area of a Protogynous Teleost,
2016Co-Authors: Thalassoma Bifasciatum, Mary Beth Hawkins, Katherine Mccaffrey, John GodwinAbstract:The highly conserved members of the zic family of zinc-finger transcription factors are primarily known for their roles in embryonic signaling pathways and regulation of cellular proliferation and differentiation. This study describes sexual phenotype differences in abundances of zic2 mRNA in the Preoptic Area of the hypothalamus, a region strongly implicated in sexual behavior and function, in an adult teleost, Thalassoma bifasciatum. The bluehead wrasse (Thalassoma bifasciatum) is a valuable model for studying neuroendocrine processes because it displays two discrete male phenotypes, initial phase (IP) males and territorial, terminal phase (TP) males, and undergoes socially-controlled protogynous sex change. Previously generated microarray-based comparisons suggested that zic2 was upregulated in the brains of terminal phase males relative to initial phase males. To further explore this difference, we cloned a 727 bp sequence for neural zic2 from field-collected animals. Riboprobe-based in situ hybridization was employed to localize zic2 signal in adult bluehead brains and assess the relative abundance of brain zic2 mRNA across sexual phenotypes. We found zic2 mRNA expression was extremely abundant in the granular cells of the cerebellum and widespread in other brain regions including in the thalamus, hypothalamus, habenula, torus semicircularis, torus longitudinalis, medial longitudinal fascicle and telencephalic Areas. Quantitative autoradiography and phosphorimaging showed zic2 mRNA hybridization signal in the Preoptic Area of the hypothalamus was significantly higher in terminal phase males relative to both initial phase males and females, and silve
-
sexual phenotype differences in zic2 mrna abundance in the Preoptic Area of a protogynous teleost thalassoma bifasciatum
PLOS ONE, 2011Co-Authors: Katherine A Mccaffrey, Mary Beth Hawkins, John GodwinAbstract:The highly conserved members of the zic family of zinc-finger transcription factors are primarily known for their roles in embryonic signaling pathways and regulation of cellular proliferation and differentiation. This study describes sexual phenotype differences in abundances of zic2 mRNA in the Preoptic Area of the hypothalamus, a region strongly implicated in sexual behavior and function, in an adult teleost, Thalassoma bifasciatum. The bluehead wrasse (Thalassoma bifasciatum) is a valuable model for studying neuroendocrine processes because it displays two discrete male phenotypes, initial phase (IP) males and territorial, terminal phase (TP) males, and undergoes socially-controlled protogynous sex change. Previously generated microarray-based comparisons suggested that zic2 was upregulated in the brains of terminal phase males relative to initial phase males. To further explore this difference, we cloned a 727 bp sequence for neural zic2 from field-collected animals. Riboprobe-based in situ hybridization was employed to localize zic2 signal in adult bluehead brains and assess the relative abundance of brain zic2 mRNA across sexual phenotypes. We found zic2 mRNA expression was extremely abundant in the granular cells of the cerebellum and widespread in other brain regions including in the thalamus, hypothalamus, habenula, torus semicircularis, torus longitudinalis, medial longitudinal fascicle and telencephalic Areas. Quantitative autoradiography and phosphorimaging showed zic2 mRNA hybridization signal in the Preoptic Area of the hypothalamus was significantly higher in terminal phase males relative to both initial phase males and females, and silver grain analysis confirmed this relationship between phenotypes. No significant difference in abundance was found in zic2 signal across phenotypes in the habenula, a brain region not implicated in the control of sexual behavior, or cerebellum.
Stuart A Tobet - One of the best experts on this subject based on the ideXlab platform.
-
estrogen modulates neuronal movements within the developing Preoptic Area anterior hypothalamus
European Journal of Neuroscience, 2007Co-Authors: John Gabriel Knoll, Cory Wolfe, Stuart A TobetAbstract:The Preoptic Area/anterior hypothalamus (POA/AH) is characterized by sexually dimorphic features in a number of vertebrates and is a key region of the forebrain for regulating physiological responses and sexual behaviors. Using live-cell, fluorescent video microscopy with organotypic brain slices the current study examined sex differences in the movement characteristics of neurons expressing yellow fluorescent protein (YFP) driven by the Thy-1 promoter. Cells in slices from embryonic day 14 (E14), but not E13 mice displayed significant sex differences in their basal neuronal movement characteristics. Exposure to 10nM estradiol-17β (E2), but not 100nM dihydrotestosterone, significantly altered cell movement characteristics within minutes of exposure in a location specific manner. E2 treatment decreased the rate of motion of cells located in the dorsal POA/AH, but increased the frequency of movement in cells located more ventrally. These effects were consistent across age and sex. To further determine whether early developing sex differences in the POA/AH depend upon gonadal steroids, we examined cell positions in mice with a disruption of the steroidogenic factor-1 gene in which gonads do not form. An early born cohort of cells was labeled with the mitotic indicator bromodeoxyuridine (BrdU) on E11. More cells were found in the POA/AH of females than males on the day of birth (P0) regardless of gonadal status. These results support the hypothesis that estrogen partially contributes to brain sexual dimorphism through its influence on cell movements during development. Estrogen's influence may be superimposed upon a pre-existing genetic bias.
-
Large Somal Size Is Associated with the Expression of Galanin but Not with Neuronal Birthdate in the Sexually Dimorphic Male Nucleus of Ferret’s Preoptic Area/Anterior Hypothalamus
Neuroendocrinology, 1998Co-Authors: Joong Jean Park, Stuart A Tobet, Jayen H. Patel, Luqman K. Dad, Michael J BaumAbstract:Using Nissl and Golgi stains, a sexually dimorphic male nucleus (MN) comprised of a cluster of large cells with large dendritic arbors has been identified in the dorsal Preoptic Area/anterior hypothal
Velayudhan Mohan Kumar - One of the best experts on this subject based on the ideXlab platform.
-
Noradrenergic afferents and receptors in the medial Preoptic Area: Neuroanatomical and neurochemical links between the regulation of sleep and body temperature
Neurochemistry international, 2007Co-Authors: Velayudhan Mohan Kumar, Ramalingam Vetrivelan, Hruda Nanda MallickAbstract:Several studies have shown the importance of the medial Preoptic Area in the regulation of sleep-wakefulness and of body temperature. The medial Preoptic Area has a rich noradrenergic innervation, coming mostly from the lateral tegmental noradrenergic system. The accumulating evidences show that the noradrenergic afferents to the medial Preoptic Area are involved in the induction of sleep. This hypnogenic mechanism operates through the postsynaptic alpha1 and alpha2-adrenergic receptors. Noradrenergic afferents are also involved in the thermoregulatory mechanisms, and the activation of these fibers brings about a fall in body temperature. Though the body temperature changes are brought about by the same receptor subtypes as those involved in hypnogenesis, observations suggest the possibility of separate sets of noradrenergic afferents in the medial Preoptic Area for sleep regulation and thermoregulation. In this review, we present the compelling evidences, which showed that the noradrenergic afferents of the medial Preoptic Area bring about a fall in body temperature and other thermoregulatory behavioral alterations associated with sleep.
-
alpha 1 adrenergic receptors in the medial Preoptic Area are involved in the induction of sleep
Neurochemical Research, 2006Co-Authors: Velayudhan Mohan Kumar, Ramalingam Vetrivelan, Hruda Nanda MallickAbstract:This paper reviews the recent studies that led to the conclusion that the noradrenergic neurons projecting to the medial Preoptic Area (mPOA) are hypnogenic and that they mediate this action through α1 adrenergic receptors. Microinjection of noradrenaline (NA) into the mPOA induced arousal. Studies using α2 adrenergic drugs showed that the arousal induced by intraPreoptic injection of NA was due to its action on presynaptic α2 adrenergic receptors. A combination of lesion and chemical stimulation techniques demonstrated that when NA acted on the postsynaptic α1 receptors in the mPOA, it induced sleep. IntraPreoptic injection of α1 agonist, methoxamine could induce sleep, when the hypothermia, which was simultaneously produced, was behaviorally compensated for by the animal. Increased arousal produced by the destruction of noradrenergic fibers in the mPOA further confirmed the hypnogenic role of these fibers.
-
the role of alpha 2 receptors in the medial Preoptic Area in the regulation of sleep wakefulness and body temperature
Neuroscience, 1998Co-Authors: V Ramesh, Velayudhan Mohan KumarAbstract:The study was conducted on 48 free-moving male rats to find out the role of the medial Preoptic alpha2 receptors in the regulation of sleep and body temperature. Recording electrodes for assessment of sleep-wakefulness, and injector cannulae for injection of drugs in the medial Preoptic Area were chronically fixed on the skulls of the animals. The noradrenergic fibres projecting to the medial Preoptic Area were destroyed in 24 rats by administration of 6-hydroxydopamine at the ventral noradrenergic bundle. Though arousal was produced in normal rats by the injection of the alpha2 adrenergic agonist, clonidine, at the medial Preoptic Area, it induced sedation in rats with noradrenergic fibre lesion. Clonidine did not alter the rectal temperature in normal rats but it induced hypothermia in lesioned rats. Injection of alpha2 antagonist, yohimbine, at the medial Preoptic Area induced sleep in rats with intact noradrenergic fibres. However, the sleep inducing effect of this drug was very much attenuated in the lesioned animals. There was no significant change in body temperature, in both these groups of animals, after yohimbine administration. The study indicates the role of presynaptic alpha2 adrenergic receptors in arousal response and indirectly supports the contention that the alpha1 postsynaptic receptors at the medial Preoptic Area are involved in hypnogenesis. It also suggests that the thermal changes induced by adrenergic system are mediated through alpha1 postsynaptic receptors. But the thermal changes do not contribute towards the induced alterations in sleep-wakefulness. It is proposed that there should be separate sets of noradrenergic terminals for regulation of sleep and body temperature.
Hengerer Bastian - One of the best experts on this subject based on the ideXlab platform.
-
Activation of the medial Preoptic Area (MPOA) ameliorates loss of maternal behavior in a Shank2 mouse model for autism
'EMBO', 2021Co-Authors: Grabrucker Stefanie, Pagano Jessica, Schweizer Johanna, Urrutia-ruiz Carolina, Schon Michael, Thome Kevin, Ehret Gunter, Grabrucker, Andreas M., Zhang Rong, Hengerer BastianAbstract:peer-reviewedImpairments in social relationships and awareness are features observed in autism spectrum disorders (ASDs). However, the under lying mechanisms remain poorly understood. Shank2 is a high-confi dence ASD candidate gene and localizes primarily to postsynaptic densities (PSDs) of excitatory synapses in the central nervous system (CNS). We show here that loss of Shank2 in mice leads to a lack of social attachment and bonding behavior towards pubs independent of hormonal, cognitive, or sensitive deficits. Shank2 / mice display functional changes in nuclei of the social attachment circuit that were most prominent in the medial Preoptic Area (MPOA) of the hypothalamus. Selective enhancement of MPOA activity by DREADD technology re-established social bonding behavior in Shank2 / mice, providing evidence that the identified circuit might be crucial for explaining how social deficits in ASD can arise
Bastian Hengerer - One of the best experts on this subject based on the ideXlab platform.
-
Activation of the medial Preoptic Area (MPOA) ameliorates loss of maternal behavior in a Shank2 mouse model for autism
The EMBO journal, 2021Co-Authors: Stefanie Grabrucker, Jessica Pagano, Johanna Schweizer, Carolina Urrutia-ruiz, Michael Schön, Kevin Thome, Günter Ehret, Andreas M. Grabrucker, Rong Zhang, Bastian HengererAbstract:Impairments in social relationships and awareness are features observed in autism spectrum disorders (ASDs). However, the underlying mechanisms remain poorly understood. Shank2 is a high-confidence ASD candidate gene and localizes primarily to postsynaptic densities (PSDs) of excitatory synapses in the central nervous system (CNS). We show here that loss of Shank2 in mice leads to a lack of social attachment and bonding behavior towards pubs independent of hormonal, cognitive, or sensitive deficits. Shank2-/- mice display functional changes in nuclei of the social attachment circuit that were most prominent in the medial Preoptic Area (MPOA) of the hypothalamus. Selective enhancement of MPOA activity by DREADD technology re-established social bonding behavior in Shank2-/- mice, providing evidence that the identified circuit might be crucial for explaining how social deficits in ASD can arise.
