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Julian G Mercer - One of the best experts on this subject based on the ideXlab platform.

  • b219 ob r 5 utr and Leptin Receptor gene related protein gene expression in mouse brain and placenta tissue specific Leptin Receptor promoter activity
    Journal of Neuroendocrinology, 2001
    Co-Authors: Julian G Mercer, Nigel Hoggard, Kimmarie Moar, A D Strosberg, Philippe Froguel, Bernard Bailleul
    Abstract:

    Leptin Receptor (OB-R) splice variants either encode proteins with different 3' cytoplasmic domains or have different 5' untranslated regions (UTR), indicative of dual promoters. The B219/OB-R promoter transcribes only OB-R transcripts, whereas the OB-R/GRP promoter initiates transcription of both OB-R and another protein of unknown function, called the Leptin Receptor gene-related protein (OB-RGRP). We compared expression of B219/OB-R 5'-UTR and OB-RGRP mRNAs by in situ hybridization. We thus assessed, by inference, the contributions of the two promoters to the Leptin Receptor transcript pool, in murine brain or in placenta, a tissue with abundant Leptin Receptor mRNA. Expression of B219/OB-R 5'-UTR mRNA (and thus by inference B219/OB-R promoter activity) in brain was similar in both distribution and relative intensity to OB-R mRNA. OB-RGRP mRNA (and thus by inference OB-R/GRP promoter activity) was widely distributed in murine brain, with elevated expression in the hypothalamic regions that express the Leptin Receptor mRNA, including the paraventricular nucleus. B219/OB-R 5'-UTR mRNA, but not OB-RGRP mRNA, was upregulated in hypothalamus of obese ob/ob mice. In placenta, B219/OB-R 5'-UTR mRNA was restricted to the maternal interface, and transcription of both long and short Leptin Receptor splice variants in the main body of the tissue thus proceeds via the OB-R/GRP promoter, strongly indicative of tissue-specific promoter usage.

  • Leptin and Leptin Receptor mrna and protein expression in the murine fetus and placenta
    Proceedings of the National Academy of Sciences of the United States of America, 1997
    Co-Authors: Nigel Hoggard, Paul Trayhurn, Lynda Williams, Leif Hunter, Jacqueline S Duncan, Julian G Mercer
    Abstract:

    Leptin is a 167-aa protein that is secreted from adipose tissue and is important in the regulation of energy balance. It also functions in hematopoiesis and reproduction. To assess whether Leptin is involved in fetal growth and development we have examined the distribution of mRNAs encoding Leptin and the Leptin Receptor (which has at least six splice variants) in the 14.5-day postcoitus mouse fetus and in the placenta using reverse transcription–PCR and in situ hybridization. High levels of gene expression for Leptin, the Leptin Receptor, and the long splice variant of the Leptin Receptor with an intracellular signaling domain were observed in the placenta, fetal cartilage/bone, and hair follicles. Receptor expression also was detected in the lung, as well as the leptomeninges and choroid plexus of the fetal brain. Western blotting and immunocytochemistry, using specific antibodies, demonstrated the presence of Leptin and Leptin Receptor protein in these tissues. These results suggest that Leptin may play a role in the growth and development of the fetus, both through placental and fetal expression of the Leptin and Leptin Receptor genes. In the fetus, Leptin may be multifunctional and have both paracrine and endocrine effects.

  • localization of Leptin Receptor mrna splice variants in murine peripheral tissues by rt pcr and in situ hybridization
    Biochemical and Biophysical Research Communications, 1997
    Co-Authors: Nigel Hoggard, Paul Trayhurn, Julian G Mercer, Kimmarie Moar, Vernon D Rayner, Lynda Williams
    Abstract:

    Expression of Leptin Receptor splice variants, including the long form variant (Ob-Rb), has been examined in murine peripheral tissues. RT-PCR indicates that the Leptin Receptor, Ob-R, and in particular the Ob-Ra splice variant are expressed in a wide range of tissues. Expression of the Ob-R Receptor was localized by in situ hybridization to specific sites in the spleen, testes, kidney, liver, lung, and adrenal. However, the long form Leptin Receptor, Ob-Rb, was only expressed at significant levels in the medulla of the adrenal and the inner zone of the medulla of the kidney. The specific sites of expression of different splice variants within peripheral tissues has important implications with regard to the function of Leptin.

  • coexpression of Leptin Receptor and preproneuropeptide y mrna in arcuate nucleus of mouse hypothalamus
    Journal of Neuroendocrinology, 1996
    Co-Authors: Julian G Mercer, L T Hannah, Nigel Hoggard, Lynda Williams, C B Lawrence, Peter J Morgan, Paul Trayhurn
    Abstract:

    Leptin, the protein product of the adipose tissue-specific ob (obese) gene (1), reduces the body weight, adiposity and food intake of obese ob/ob mice on peripheral or central injection (2, 3, 4). [125I]Leptin binding has been detected in mouse choroid plexus (5), from which a Leptin Receptor gene was expression cloned (5). The gene has at least 6 splice variants (6, 7). Leptin Receptor mRNA was localized in the hypothalamus by in situ hybridization being particularly abundantly expressed in the arcuate nucleus (8). There is evidence linking the physiological effects of injected Leptin with hypothalamic neuropeptide Y (9, 10) (NPY), which has potent central effects on food intake and energy balance (11), and is also expressed in the arcuate nucleus. Here we report dual in situ hybridization studies for Leptin Receptor and NPY gene expression in the mouse arcuate nucleus, where the majority of cells examined expressed both genes. This provides the first direct evidence that Leptin acts on cells that express NPY mRNA.

  • localization of Leptin Receptor mrna and the long form splice variant ob rb in mouse hypothalamus and adjacent brain regions by in situ hybridization
    FEBS Letters, 1996
    Co-Authors: Julian G Mercer, Bruce C Lawrence, L T Hannah, Lynda M. Williams, Nigel Hoggard, Paul Trayhurn
    Abstract:

    Expression of the Leptin Receptor gene has been examined in mouse hypothalamus and other brain regions by in situ hybridization. With a probe recognizing all the known splice variants, Receptor mRNA was evident in several brain regions (cortex, hippocampus, thalamus), with strong expression in the hypothalamus (arcuate, ventromedial, paraventricular and ventral premammillary nuclei), choroid plexus and leptomeninges. A probe specific to the long splice variant of the Leptin Receptor (Ob-Rb), containing the putative intracellular signaling domain, again revealed strong expression in the hypothalamus; there was, however, minimal hybridization to choroid plexus and leptomeninges. These results indicate that the hypothalamus is a key site of Leptin action, although other brain regions are also targeted.

Paul Trayhurn - One of the best experts on this subject based on the ideXlab platform.

  • Leptin and Leptin Receptor mrna and protein expression in the murine fetus and placenta
    Proceedings of the National Academy of Sciences of the United States of America, 1997
    Co-Authors: Nigel Hoggard, Paul Trayhurn, Lynda Williams, Leif Hunter, Jacqueline S Duncan, Julian G Mercer
    Abstract:

    Leptin is a 167-aa protein that is secreted from adipose tissue and is important in the regulation of energy balance. It also functions in hematopoiesis and reproduction. To assess whether Leptin is involved in fetal growth and development we have examined the distribution of mRNAs encoding Leptin and the Leptin Receptor (which has at least six splice variants) in the 14.5-day postcoitus mouse fetus and in the placenta using reverse transcription–PCR and in situ hybridization. High levels of gene expression for Leptin, the Leptin Receptor, and the long splice variant of the Leptin Receptor with an intracellular signaling domain were observed in the placenta, fetal cartilage/bone, and hair follicles. Receptor expression also was detected in the lung, as well as the leptomeninges and choroid plexus of the fetal brain. Western blotting and immunocytochemistry, using specific antibodies, demonstrated the presence of Leptin and Leptin Receptor protein in these tissues. These results suggest that Leptin may play a role in the growth and development of the fetus, both through placental and fetal expression of the Leptin and Leptin Receptor genes. In the fetus, Leptin may be multifunctional and have both paracrine and endocrine effects.

  • localization of Leptin Receptor mrna splice variants in murine peripheral tissues by rt pcr and in situ hybridization
    Biochemical and Biophysical Research Communications, 1997
    Co-Authors: Nigel Hoggard, Paul Trayhurn, Julian G Mercer, Kimmarie Moar, Vernon D Rayner, Lynda Williams
    Abstract:

    Expression of Leptin Receptor splice variants, including the long form variant (Ob-Rb), has been examined in murine peripheral tissues. RT-PCR indicates that the Leptin Receptor, Ob-R, and in particular the Ob-Ra splice variant are expressed in a wide range of tissues. Expression of the Ob-R Receptor was localized by in situ hybridization to specific sites in the spleen, testes, kidney, liver, lung, and adrenal. However, the long form Leptin Receptor, Ob-Rb, was only expressed at significant levels in the medulla of the adrenal and the inner zone of the medulla of the kidney. The specific sites of expression of different splice variants within peripheral tissues has important implications with regard to the function of Leptin.

  • coexpression of Leptin Receptor and preproneuropeptide y mrna in arcuate nucleus of mouse hypothalamus
    Journal of Neuroendocrinology, 1996
    Co-Authors: Julian G Mercer, L T Hannah, Nigel Hoggard, Lynda Williams, C B Lawrence, Peter J Morgan, Paul Trayhurn
    Abstract:

    Leptin, the protein product of the adipose tissue-specific ob (obese) gene (1), reduces the body weight, adiposity and food intake of obese ob/ob mice on peripheral or central injection (2, 3, 4). [125I]Leptin binding has been detected in mouse choroid plexus (5), from which a Leptin Receptor gene was expression cloned (5). The gene has at least 6 splice variants (6, 7). Leptin Receptor mRNA was localized in the hypothalamus by in situ hybridization being particularly abundantly expressed in the arcuate nucleus (8). There is evidence linking the physiological effects of injected Leptin with hypothalamic neuropeptide Y (9, 10) (NPY), which has potent central effects on food intake and energy balance (11), and is also expressed in the arcuate nucleus. Here we report dual in situ hybridization studies for Leptin Receptor and NPY gene expression in the mouse arcuate nucleus, where the majority of cells examined expressed both genes. This provides the first direct evidence that Leptin acts on cells that express NPY mRNA.

  • localization of Leptin Receptor mrna and the long form splice variant ob rb in mouse hypothalamus and adjacent brain regions by in situ hybridization
    FEBS Letters, 1996
    Co-Authors: Julian G Mercer, Bruce C Lawrence, L T Hannah, Lynda M. Williams, Nigel Hoggard, Paul Trayhurn
    Abstract:

    Expression of the Leptin Receptor gene has been examined in mouse hypothalamus and other brain regions by in situ hybridization. With a probe recognizing all the known splice variants, Receptor mRNA was evident in several brain regions (cortex, hippocampus, thalamus), with strong expression in the hypothalamus (arcuate, ventromedial, paraventricular and ventral premammillary nuclei), choroid plexus and leptomeninges. A probe specific to the long splice variant of the Leptin Receptor (Ob-Rb), containing the putative intracellular signaling domain, again revealed strong expression in the hypothalamus; there was, however, minimal hybridization to choroid plexus and leptomeninges. These results indicate that the hypothalamus is a key site of Leptin action, although other brain regions are also targeted.

Nigel Hoggard - One of the best experts on this subject based on the ideXlab platform.

  • b219 ob r 5 utr and Leptin Receptor gene related protein gene expression in mouse brain and placenta tissue specific Leptin Receptor promoter activity
    Journal of Neuroendocrinology, 2001
    Co-Authors: Julian G Mercer, Nigel Hoggard, Kimmarie Moar, A D Strosberg, Philippe Froguel, Bernard Bailleul
    Abstract:

    Leptin Receptor (OB-R) splice variants either encode proteins with different 3' cytoplasmic domains or have different 5' untranslated regions (UTR), indicative of dual promoters. The B219/OB-R promoter transcribes only OB-R transcripts, whereas the OB-R/GRP promoter initiates transcription of both OB-R and another protein of unknown function, called the Leptin Receptor gene-related protein (OB-RGRP). We compared expression of B219/OB-R 5'-UTR and OB-RGRP mRNAs by in situ hybridization. We thus assessed, by inference, the contributions of the two promoters to the Leptin Receptor transcript pool, in murine brain or in placenta, a tissue with abundant Leptin Receptor mRNA. Expression of B219/OB-R 5'-UTR mRNA (and thus by inference B219/OB-R promoter activity) in brain was similar in both distribution and relative intensity to OB-R mRNA. OB-RGRP mRNA (and thus by inference OB-R/GRP promoter activity) was widely distributed in murine brain, with elevated expression in the hypothalamic regions that express the Leptin Receptor mRNA, including the paraventricular nucleus. B219/OB-R 5'-UTR mRNA, but not OB-RGRP mRNA, was upregulated in hypothalamus of obese ob/ob mice. In placenta, B219/OB-R 5'-UTR mRNA was restricted to the maternal interface, and transcription of both long and short Leptin Receptor splice variants in the main body of the tissue thus proceeds via the OB-R/GRP promoter, strongly indicative of tissue-specific promoter usage.

  • Leptin and Leptin Receptor mrna and protein expression in the murine fetus and placenta
    Proceedings of the National Academy of Sciences of the United States of America, 1997
    Co-Authors: Nigel Hoggard, Paul Trayhurn, Lynda Williams, Leif Hunter, Jacqueline S Duncan, Julian G Mercer
    Abstract:

    Leptin is a 167-aa protein that is secreted from adipose tissue and is important in the regulation of energy balance. It also functions in hematopoiesis and reproduction. To assess whether Leptin is involved in fetal growth and development we have examined the distribution of mRNAs encoding Leptin and the Leptin Receptor (which has at least six splice variants) in the 14.5-day postcoitus mouse fetus and in the placenta using reverse transcription–PCR and in situ hybridization. High levels of gene expression for Leptin, the Leptin Receptor, and the long splice variant of the Leptin Receptor with an intracellular signaling domain were observed in the placenta, fetal cartilage/bone, and hair follicles. Receptor expression also was detected in the lung, as well as the leptomeninges and choroid plexus of the fetal brain. Western blotting and immunocytochemistry, using specific antibodies, demonstrated the presence of Leptin and Leptin Receptor protein in these tissues. These results suggest that Leptin may play a role in the growth and development of the fetus, both through placental and fetal expression of the Leptin and Leptin Receptor genes. In the fetus, Leptin may be multifunctional and have both paracrine and endocrine effects.

  • localization of Leptin Receptor mrna splice variants in murine peripheral tissues by rt pcr and in situ hybridization
    Biochemical and Biophysical Research Communications, 1997
    Co-Authors: Nigel Hoggard, Paul Trayhurn, Julian G Mercer, Kimmarie Moar, Vernon D Rayner, Lynda Williams
    Abstract:

    Expression of Leptin Receptor splice variants, including the long form variant (Ob-Rb), has been examined in murine peripheral tissues. RT-PCR indicates that the Leptin Receptor, Ob-R, and in particular the Ob-Ra splice variant are expressed in a wide range of tissues. Expression of the Ob-R Receptor was localized by in situ hybridization to specific sites in the spleen, testes, kidney, liver, lung, and adrenal. However, the long form Leptin Receptor, Ob-Rb, was only expressed at significant levels in the medulla of the adrenal and the inner zone of the medulla of the kidney. The specific sites of expression of different splice variants within peripheral tissues has important implications with regard to the function of Leptin.

  • coexpression of Leptin Receptor and preproneuropeptide y mrna in arcuate nucleus of mouse hypothalamus
    Journal of Neuroendocrinology, 1996
    Co-Authors: Julian G Mercer, L T Hannah, Nigel Hoggard, Lynda Williams, C B Lawrence, Peter J Morgan, Paul Trayhurn
    Abstract:

    Leptin, the protein product of the adipose tissue-specific ob (obese) gene (1), reduces the body weight, adiposity and food intake of obese ob/ob mice on peripheral or central injection (2, 3, 4). [125I]Leptin binding has been detected in mouse choroid plexus (5), from which a Leptin Receptor gene was expression cloned (5). The gene has at least 6 splice variants (6, 7). Leptin Receptor mRNA was localized in the hypothalamus by in situ hybridization being particularly abundantly expressed in the arcuate nucleus (8). There is evidence linking the physiological effects of injected Leptin with hypothalamic neuropeptide Y (9, 10) (NPY), which has potent central effects on food intake and energy balance (11), and is also expressed in the arcuate nucleus. Here we report dual in situ hybridization studies for Leptin Receptor and NPY gene expression in the mouse arcuate nucleus, where the majority of cells examined expressed both genes. This provides the first direct evidence that Leptin acts on cells that express NPY mRNA.

  • localization of Leptin Receptor mrna and the long form splice variant ob rb in mouse hypothalamus and adjacent brain regions by in situ hybridization
    FEBS Letters, 1996
    Co-Authors: Julian G Mercer, Bruce C Lawrence, L T Hannah, Lynda M. Williams, Nigel Hoggard, Paul Trayhurn
    Abstract:

    Expression of the Leptin Receptor gene has been examined in mouse hypothalamus and other brain regions by in situ hybridization. With a probe recognizing all the known splice variants, Receptor mRNA was evident in several brain regions (cortex, hippocampus, thalamus), with strong expression in the hypothalamus (arcuate, ventromedial, paraventricular and ventral premammillary nuclei), choroid plexus and leptomeninges. A probe specific to the long splice variant of the Leptin Receptor (Ob-Rb), containing the putative intracellular signaling domain, again revealed strong expression in the hypothalamus; there was, however, minimal hybridization to choroid plexus and leptomeninges. These results indicate that the hypothalamus is a key site of Leptin action, although other brain regions are also targeted.

Lynda Williams - One of the best experts on this subject based on the ideXlab platform.

  • Leptin and Leptin Receptor mrna and protein expression in the murine fetus and placenta
    Proceedings of the National Academy of Sciences of the United States of America, 1997
    Co-Authors: Nigel Hoggard, Paul Trayhurn, Lynda Williams, Leif Hunter, Jacqueline S Duncan, Julian G Mercer
    Abstract:

    Leptin is a 167-aa protein that is secreted from adipose tissue and is important in the regulation of energy balance. It also functions in hematopoiesis and reproduction. To assess whether Leptin is involved in fetal growth and development we have examined the distribution of mRNAs encoding Leptin and the Leptin Receptor (which has at least six splice variants) in the 14.5-day postcoitus mouse fetus and in the placenta using reverse transcription–PCR and in situ hybridization. High levels of gene expression for Leptin, the Leptin Receptor, and the long splice variant of the Leptin Receptor with an intracellular signaling domain were observed in the placenta, fetal cartilage/bone, and hair follicles. Receptor expression also was detected in the lung, as well as the leptomeninges and choroid plexus of the fetal brain. Western blotting and immunocytochemistry, using specific antibodies, demonstrated the presence of Leptin and Leptin Receptor protein in these tissues. These results suggest that Leptin may play a role in the growth and development of the fetus, both through placental and fetal expression of the Leptin and Leptin Receptor genes. In the fetus, Leptin may be multifunctional and have both paracrine and endocrine effects.

  • localization of Leptin Receptor mrna splice variants in murine peripheral tissues by rt pcr and in situ hybridization
    Biochemical and Biophysical Research Communications, 1997
    Co-Authors: Nigel Hoggard, Paul Trayhurn, Julian G Mercer, Kimmarie Moar, Vernon D Rayner, Lynda Williams
    Abstract:

    Expression of Leptin Receptor splice variants, including the long form variant (Ob-Rb), has been examined in murine peripheral tissues. RT-PCR indicates that the Leptin Receptor, Ob-R, and in particular the Ob-Ra splice variant are expressed in a wide range of tissues. Expression of the Ob-R Receptor was localized by in situ hybridization to specific sites in the spleen, testes, kidney, liver, lung, and adrenal. However, the long form Leptin Receptor, Ob-Rb, was only expressed at significant levels in the medulla of the adrenal and the inner zone of the medulla of the kidney. The specific sites of expression of different splice variants within peripheral tissues has important implications with regard to the function of Leptin.

  • coexpression of Leptin Receptor and preproneuropeptide y mrna in arcuate nucleus of mouse hypothalamus
    Journal of Neuroendocrinology, 1996
    Co-Authors: Julian G Mercer, L T Hannah, Nigel Hoggard, Lynda Williams, C B Lawrence, Peter J Morgan, Paul Trayhurn
    Abstract:

    Leptin, the protein product of the adipose tissue-specific ob (obese) gene (1), reduces the body weight, adiposity and food intake of obese ob/ob mice on peripheral or central injection (2, 3, 4). [125I]Leptin binding has been detected in mouse choroid plexus (5), from which a Leptin Receptor gene was expression cloned (5). The gene has at least 6 splice variants (6, 7). Leptin Receptor mRNA was localized in the hypothalamus by in situ hybridization being particularly abundantly expressed in the arcuate nucleus (8). There is evidence linking the physiological effects of injected Leptin with hypothalamic neuropeptide Y (9, 10) (NPY), which has potent central effects on food intake and energy balance (11), and is also expressed in the arcuate nucleus. Here we report dual in situ hybridization studies for Leptin Receptor and NPY gene expression in the mouse arcuate nucleus, where the majority of cells examined expressed both genes. This provides the first direct evidence that Leptin acts on cells that express NPY mRNA.

Bjorn Meister - One of the best experts on this subject based on the ideXlab platform.

  • Leptin Receptor and stat3 immunoreactivities in hypocretin orexin neurones of the lateral hypothalamus
    Journal of Neuroendocrinology, 2001
    Co-Authors: Marielouise Hakansson, Luis De Lecea, J G Sutcliffe, Bjorn Meister
    Abstract:

    Hypocretins/orexins are recently characterized peptides that are synthesized in neurones of the lateral hypohalamus and stimulate food intake in rats. To clarify whether Leptin may interact with hypocretin/orexin to reduce ingestive behaviour, the presence of Leptin Receptor-immunoreactivity in hypocretin/orexin-containing neurones was examined. Many Leptin Receptor-and hypocretin/orexin-immunoreactive neurones were demonstrated in the lateral hypothalamic area and perifornical region. Both direct double-labelling and elution-restaining methods showed that Leptin Receptor-immunoreactivity was present in the vast majority of hypocretin/orexin-containing neurones. Immunoreactivity for STAT3, a transcription factor activated by Leptin, was also demonstrated in hypocretin/orexin-containing neurones. Isolated hypocretin/orexin cell bodies in the dorsal part of the lateral hypothalamic area and the ventral perifornical region were shown to contain immunoreactivity for galanin, another peptide known to affect feeding. Galanin neurones were also seen to contain Leptin Receptor-and STAT3-immunoreactivity. Melanin-concentrating hormone (MCH)-containing neurones constituted a cell population within the lateral hypothalamus distinct from the one containing hypocretin/orexin-immunoreactivity, as shown by elution-restaining methodology. The presence of Leptin Receptor-and STAT3-immunoreactivities in hypocretin/orexin-containing neurones of the lateral hypothalamus suggests that Leptin may directly regulate these hypothalamic neurones, most likely via an inhibitory action on hypocretin/orexin expression and/or secretion resulting in reduced food intake.

  • expression and regulation of Leptin Receptor proteins in afferent and efferent neurons of the vagus nerve
    European Journal of Neuroscience, 2001
    Co-Authors: Marion Buyse, Gabriel Péranzi, Bjorn Meister, L Moizo, Sandra Guilmeau, Marielouise Ovesjo, Helene Goiot, Francine Walker, Miguel J M Lewin, Andre Bado
    Abstract:

    : Leptin, the product of the ob gene, plays a key role in the regulation of food intake via a cross-talk between hypothalamic Leptin Receptors and neuropeptides that affect feeding behaviour. Recent studies have shown a synergistic interaction between Leptin and cholecystokinin (CCK) leading to suppression of food intake, which involves CCK-1 Receptors and capsaicin-sensitive vagal fibres. In this study, we have investigated the presence of Leptin Receptors in afferent and efferent neurons of the vagus nerve. By using reverse transcription-polymerase chain reaction, mRNAs encoding long (Ob-Rb) and short (Ob-Ra) Leptin Receptor isoforms were detected in the rat nodose ganglion, which contains the cell bodies of the vagal afferent neurons. Western blot analysis confirmed the presence of Leptin Receptor-immunoreactive proteins in extracts from the vagal trunk. Immunohistochemistry showed the presence of Leptin Receptors and the Leptin-induced transcription factor STAT3 in the cytoplasm of nodose ganglion cells. In cervical vagal segments, levels of Leptin Receptor protein displayed physiological regulation, with decreased amounts after feeding and increased levels after food restriction. In addition, Leptin Receptor and STAT3 immunoreactivities were detected in neurons of the nucleus of tractus solitarius (NTS) and the dorsal motor nucleus of the vagus nerve (DMNX) by immunofluorescence histochemistry. Furthermore, direct double-labelling demonstrated colocalization of Ob-Rb and STAT3 immunoreactivities in cholinergic vagal efferent cell bodies of the DMNX. It is speculated that vagal Leptin Receptors, apart from being activated by adipocyte-derived Leptin, may also be influenced by Leptin produced by the stomach. This may explain the synergistic action of Leptin and CCK on neuronal activity in the NTS and on food intake.

  • expression of Leptin Receptor mrna in the hypothalamic arcuate nucleus relationship with npy neurones
    Neuroreport, 1996
    Co-Authors: Marielouise Hakansson, Annalena Hulting, Bjorn Meister
    Abstract:

    THE obese phentotype of ob/ob mice is linked to a mutation in the ob gene that results in expression of a truncated inactive protein. The ob gene product, Leptin, is synthesized in adipose tissue and is a circulating factor that regulates body weight. Leptin Receptors were recently cloned and a mutation in the Leptin Receptor gene in obese db/db mice was identified. Leptin Receptor mRNA has been detected in brain, including hypothalamus, but the cellular localization has so far not been clarified. Here we report on the cellular localization of Leptin Receptor mRNA in the mouse brain using in situ hybridization. Strong hybridization was observed in the choroid plexus and hypothalamic arcuate nucleus. Weaker hybridization was detected in the hippocampal formation and in the cerebral cortex. Within the arcuate nucleus, cell bodies expressing Leptin Receptor mRNA were distributed in its ventromedial subdivision. Hybridization of semiadjacent sections with a probe to neuropeptide Y (NPY) showed a co-distribution of labelled cell bodies, suggesting the presence of Leptin Receptors on NPY-containing neurones.