The Experts below are selected from a list of 39 Experts worldwide ranked by ideXlab platform
Istvan Merchenthaler - One of the best experts on this subject based on the ideXlab platform.
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Distribution of estrogen receptor β immunoreactivity in the rat central nervous system
The Journal of comparative neurology, 2001Co-Authors: Paul J. Shughrue, Istvan MerchenthalerAbstract:The discovery of estrogen receptor beta (ER beta) and subsequent localization of its mRNA in the rat central nervous system (CNS) has provided new insights about estrogen action in brain. A critical step in understanding the role of ER beta is demonstrating that the mRNA is translated into functional protein. The present study used a new ER beta-specific polyclonal antiserum (Z8P) and immunocytochemistry (ICC) to investigate the distribution of ER beta in the rat CNS. Ovariectomized female rats were perfusion fixed, and free-floating sections were incubated with Z8P. After visualization with a standard ABC method, nuclear immunoreactivity was seen in neurons throughout the brain, including the olfactory nuclei, laminae IV-VI of the cerebral cortex, medial septum, preoptic area, bed Nucleus of the stria terminalis, supraoptic Nucleus, paraventricular Nucleus, zona incerta, medial and cortical amygdaloid nuclei, Cerebellum, Nucleus of the solitary tract, ventral tegmental area, and spinal trigeminal Nucleus. Moreover, the results of a double-label ICC/ in situ hybridization study revealed that ER beta mRNA and immunoreactivity were colocalized in neurons of the brain, thus confirming the specificity of the antiserum. Through the use of Western blot analysis, Z8P was shown to recognize in vitro translated ER beta, but not ER alpha, as well as a 60-kDa protein from rat granulosa cells and ovary extracts. The results of these studies have demonstrated that (1) ER beta mRNA is translated into immunoreactive protein throughout the rat brain, and (2) ER beta resides in the cell Nucleus. Together, these data provide an anatomic foundation for future studies and advance our understanding of estrogen action in hypothalamic and extrahypothalamic brain regions.
Paul J. Shughrue - One of the best experts on this subject based on the ideXlab platform.
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Distribution of estrogen receptor β immunoreactivity in the rat central nervous system
The Journal of comparative neurology, 2001Co-Authors: Paul J. Shughrue, Istvan MerchenthalerAbstract:The discovery of estrogen receptor beta (ER beta) and subsequent localization of its mRNA in the rat central nervous system (CNS) has provided new insights about estrogen action in brain. A critical step in understanding the role of ER beta is demonstrating that the mRNA is translated into functional protein. The present study used a new ER beta-specific polyclonal antiserum (Z8P) and immunocytochemistry (ICC) to investigate the distribution of ER beta in the rat CNS. Ovariectomized female rats were perfusion fixed, and free-floating sections were incubated with Z8P. After visualization with a standard ABC method, nuclear immunoreactivity was seen in neurons throughout the brain, including the olfactory nuclei, laminae IV-VI of the cerebral cortex, medial septum, preoptic area, bed Nucleus of the stria terminalis, supraoptic Nucleus, paraventricular Nucleus, zona incerta, medial and cortical amygdaloid nuclei, Cerebellum, Nucleus of the solitary tract, ventral tegmental area, and spinal trigeminal Nucleus. Moreover, the results of a double-label ICC/ in situ hybridization study revealed that ER beta mRNA and immunoreactivity were colocalized in neurons of the brain, thus confirming the specificity of the antiserum. Through the use of Western blot analysis, Z8P was shown to recognize in vitro translated ER beta, but not ER alpha, as well as a 60-kDa protein from rat granulosa cells and ovary extracts. The results of these studies have demonstrated that (1) ER beta mRNA is translated into immunoreactive protein throughout the rat brain, and (2) ER beta resides in the cell Nucleus. Together, these data provide an anatomic foundation for future studies and advance our understanding of estrogen action in hypothalamic and extrahypothalamic brain regions.
Steven D. Douglas - One of the best experts on this subject based on the ideXlab platform.
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Detection of full-length and truncated neurokinin-1 receptor mRNA expression in human brain regions.
Journal of neuroscience methods, 2007Co-Authors: Jian-ping Lai, Avital Cnaan, Huaqing Zhao, Steven D. DouglasAbstract:We have applied a newly developed SYBR green-based real-time RT-PCR assay for quantification of full-length and truncated neurokinin-1 receptor (NK1R) mRNA expression in nine regions of human brain tissues obtained from 23 subjects who died with no evidence of neurological or neurodegenerative disease. The following brain regions were examined: cingulate cortex, Cerebellum, Nucleus accumbens, caudate Nucleus, putamen, pons, hippocampus, locus coeruleus, and basal ganglia. The SYBR green-based real-time PCR was more sensitive than TaqMan probe-based real-time PCR in amplifying both full-length and truncated NK1R mRNA. The real-time RT-PCR assay had excellent specificity and sensitivity, with a dynamic range of detection between 100 and 1,000,000 copies of the NK1R cDNA per reaction. The truncated NK1R mRNA levels were more abundant than those of the full-length NK1R in most of the regions examined and there was no significant difference in the truncated NK1R mRNA levels among the nine regions studied. There was, however, a significant difference in the expression of full-length NK1R mRNA levels among the nine regions (P=0.0024), and the putamen region expressed the highest full-length NK1R mRNA. Further studies are needed in order to examine the differences between full-length and truncated NK1R in signal transduction and functional consequences in order to delineate the significance of the co-presence of the two forms of NK1R in the human brain.
Anita Sidhu - One of the best experts on this subject based on the ideXlab platform.
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Comparative analyses of α-synuclein expression levels in rat brain tissues and transfected cells
Neuroscience letters, 2004Co-Authors: Christophe Wersinger, Melanie Banta, Anita SidhuAbstract:alpha-Synuclein may have a role in the genesis of Parkinson's disease (PD) and other neurodegenerative diseases, and overexpression of alpha-synuclein in endogenously expressing systems and transfected cell lines has been linked to its cytotoxicity. Because there is no definition of what constitutes normal or high expression levels of alpha-synuclein, the current studies were undertaken. Protein levels of alpha-synuclein, and its binding partner, the dopamine transporter (DAT), were examined and semi-quantified in different rat brain regions and compared to the amounts of alpha-synuclein expressed in Ltk(-) cells after transfection with known amounts of DNA. Of the regions tested, alpha-synuclein expression was lowest in dopamine-producing brain areas, substantia nigra and ventral tegmental area; conversely, the expression of DAT was the highest in these tissues. Areas that do not normally degenerate in PD, such as Cerebellum, Nucleus accumbens and thalamus, expressed the highest levels of alpha-synuclein and very low DAT. Expression of DAT and alpha-synuclein to levels similar to those observed in rat substantia nigra were obtained after transfection of Ltk(-) cells with 1-2 microg each of alpha-synuclein and DAT DNAs, indicating that such transfection conditions produce normal expression levels of these proteins.
Urvi Bhavsar - One of the best experts on this subject based on the ideXlab platform.
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Glycine receptors contribute to hypnosis induced by ethanol.
Alcoholism clinical and experimental research, 2009Co-Authors: Kimberly A. Sokol, Urvi BhavsarAbstract:Glycine is one of the major neurotransmitters that mediate inhibitory synaptic transmission in the central nervous system (CNS) (Betz, 1992). When bound to glycine receptors (GlyRs), glycine increases the permeability of neuronal membranes to chloride ions, thus hyperpolarizing adult mammalian neurons and producing inhibitory effects (Ye, 2008). GlyRs are highly concentrated in the lower brain stem and spinal cord (Legendre, 2001). Much evidence has been presented demonstrating the role of spinal GlyRs in the mediation of motor and sensory responses. They have been shown to control motor rhythm generation (Baldissera et al., 1981; Grillner, 1981; Grillner et al., 1998), and mediate reciprocal inhibition in stretch reflex circuits (Fyffe, 1991; Kandel et al., 2000; Lodge et al., 1977). Glycine released by the spinal Renshaw interneurons regulates motoneuron excitability and firing (Curtis et al., 1976; Fyffe, 1991; Kandel et al., 2000). GlyRs are major mediators of sensory inputs, including pain (Huang and Simpson, 2000). They are also major targets of general anesthetics, such as propofol and isoflurane (Dong and Xu, 2002; Downie et al., 1996). Current evidence clearly implicates spinal GlyRs mediate part of the immobilization produced by inhaled anesthetics (Sonner et al., 2003; Zhang et al., 2003). Accumulating evidence strongly indicates that GlyRs exist throughout the CNS (Rampon et al., 1996; Ye, 2008), including many areas of the brain, such as the prefrontal cortex, hippocampus, amygdala, hypothalamus, Cerebellum, Nucleus accumbens, ventral tegmental area, and substantia nigra (Chattipakorn and McMahon, 2002; Flint et al., 1998; Gaiarsa et al., 2002; Laube et al., 2002; Mangin et al., 2003; McCool and Botting, 2000; McCool and Farroni, 2001; Mori et al., 2002; Tapia et al., 2000; Ye et al., 1998, 1999; Zhou, 2001). In vitro studies have demonstrated that ethanol potentiates the function of GlyRs, including the GlyRs in the spinal cord and in the cerebral cortex (Aguayo and Pancetti, 1994; van Zundert et al., 2000), as well as in the midbrain (Jiang and Ye, 2003; Ye et al., 2001; Zhu and Ye, 2005). Furthermore, a structural–function relationship study has shown a binding site in GlyRs for ethanol (Mihic et al., 1997). However, the behavioral roles of brain GlyRs are not well explored. A previous in vivo study in rats has indicted the hypothalamic GABAA receptor as a contributor to the hypnosis, or loss of consciousness, induced by propofol and several other general anesthetics (Nelson et al., 2002). The GABAA receptor is the receptor for the other major inhibitory neurotransmitter in the brain. The hypothalamus is a crucial brain area in the sleep pathways. We reasoned that the GlyRs in the brain may also contribute to the hypnotic effects of CNS depressants. In support of this possibility, recent studies in our laboratory have demonstrated that the specific GlyR antagonist strychnine decreased the number of rats exhibiting loss of righting reflex (LORR) induced by propofol. Furthermore, the glycine current of hypothalamic neurons was potentiated by propofol (Nguyen et al., 2009). The object of the current study was to investigate the role of brain GlyRs in the hypnotic response to ethanol. This is accomplished via behavioral analyses on rats.