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At least 721 records · Page 40Linked to original sources
PubMed2000

Gestational profile of leptin messenger ribonucleic acid (mRNA) content in the placenta and adipose tissue in the rat, and regulation of the mRNA levels of the leptin receptor subtypes in the hypothalamus during pregnancy and lactation.

Serum leptin levels were significantly increased during rat gestation. Our data showed that leptin mRNA levels in both the adipose tissue and placenta were higher as pregnancy progressed, suggesting a role for both tissues in the hyperproduction of leptin. This paradoxical increase in leptin concentration during gestation suggests that a physiological state of leptin resistance may exist at the hypothalamic level that may explain the hyperphagia observed in pregnant rats. In order to study this issue further, levels of the mRNA encoding the different leptin receptor isoforms were determined in the hypothalamus of pregnant and nonpregnant rats. We found a specific reduction of the mRNA levels encoding the leptin receptor isoform Ob-Rb in the hypothalamus of pregnant rats compared to nonpregnant animals, suggesting that during pregnancy the hypothalamus shows a physiological resistance to the high levels of leptin due, at least in part, to a decrease in the expression of the long, biologically active form of the leptin receptor (Ob-Rb). During lactation, serum leptin levels returned to values observed in nonpregnant rats. In the hypothalami of these animals, Ob-Rb mRNA content was similar to that observed in nonpregnant rats, but we found an increased expression of some of the short forms of the leptin receptor (Ob-Re and Ob-Rf). This could contribute to induction of the hyperphagia present during lactation. These data provide new insights into the adaptive mechanisms that take place during pregnancy and lactation in order to meet increased metabolic requirements.

Adipose Tissue↗
PubMed1995

Heat Shock Disrupts Cap and Poly(A) Tail Function during Translation and Increases mRNA Stability of Introduced Reporter mRNA.

The effect of heat shock on translational efficiency and message stability of a reporter mRNA was examined in carrot (Daucus carota). Heat shock of short duration resulted in an increase in protein yield, whereas repression was observed following extended exposure to the stress. Regardless of the duration of the heat shock, a loss in the function of the 5[prime] cap [m7G(5[prime])ppp(5[prime])N, where N represents any nucleotide] and the 3[prime] poly(A) tail, two regulatory elements that work in concert to establish an efficient level of translation, was observed. This apparent paradox was resolved upon examination of the mRNA half-life following thermal stress, in which increases up to 10-fold were observed. Message stability increased as a function of the severity of the heat shock so that following a mild to moderate stress the increase in message stability more than compensated for the reduction in cap and poly(A) tail function. Following a severe heat shock, the increased mRNA half-life was not sufficient to overcome the virtual loss in cap and poly(A) tail function. No stimulation of protein synthesis was observed following a heat shock in Chinese hamster ovary cells, data suggesting that the heat-induced increases in mRNA stability may be unique to the heat-shock response in plants.

Journal Article↗
PubMed2004

Orexin-A regulates growth hormone-releasing hormone mRNA content in a nucleus-specific manner and somatostatin mRNA content in a growth hormone-dependent fashion in the rat hypothalamus.

The orexins or hypocretins are two neuropeptides involved in the regulation of diverse biological processes such as feeding, sleep and neuroendocrine function. Recent findings suggest a possible functional interaction between orexins, somatostatin and growth hormone-releasing hormone (GHRH) in the rat hypothalamus. In order to understand the possible functional linkage between orexins and these neuropeptides, we determined the effects of intracerebroventricular orexin-A administration on hypothalamic somatostatin and GHRH mRNA levels. Furthermore, we examined whether growth hormone (GH) mediates these interactions by using two animal models that showed GH deficiency: hypophysectomized rats and dwarf Lewis rats. Using in situ hybridization, our data showed that GHRH mRNA levels in the paraventricular nucleus of the hypothalamus are decreased after orexin-A treatment, without changes in the arcuate nucleus of the hypothalamus. On the other hand, orexin-A treatment induces a GH-dependent stimulatory effect on somatostatin mRNA content in the periventricular nucleus of the hypothalamus. Finally, we demonstrated, for the first time, that hypophysectomized rats and dwarf Lewis rats, two classical models of GH deficiency with alterations in sleep patterns, showed a marked reduction in the GHRH mRNA levels in the paraventricular nucleus of the hypothalamus. These data improve our understanding of the interactions among the different systems involved in the control and pathophysiology of food intake, sleep and GH secretion.

Animals↗
PubMed2005

mRNA translation is not a prerequisite for small interfering RNA-mediated mRNA cleavage.

RNA interference constitutes a major means of eliminating mRNAs, yet how the small interfering RNAs (siRNA) within the RNA-induced silencing complex (RISC) finds its homologous target in the cell remains unknown. An attractive hypothesis is that RNA interference is linked to translation which allows RISC ready access to every translated mRNA. To test whether translation could direct siRNAs to mRNAs, chemical and biological inhibitors of translation and their effects on mRNA cleavage were tested. Our results show that mRNA degradation by siRNAs is not dependent on mRNA translation.

Actins↗
PubMed1978

5'-Terminal 7-methylguanosine and mRNA function. The effect of enzymatic decapping and of cap analogs on translation of tobacco-mosaic-virus RNA and globin mRNA in vitro.

1. Decapped tobacco mosaic virus (TMV) RNA and rabbit globin mRNA were prepared by enzymic treatment of RNAs with nucleotide pyrophosphatase purified from potato. The extent of removal of 5'-terminal 7-methylguanosine 5'-monophosphate (m7GMP) from TMV RNA was at least 97% as estimated by labeling of the 5' termini in vitro with S-adenosyl[methyl-3H]methionine catalysed by vaccinia virus methyltransferases. 2. The effect of enzymic decapping was compared with the effect of cap analogs on mRNAs translation in a nuclease-treated rabbit reticulocyte lysate and in a wheat germ extract. When translation was studied at low K+ concentration, little or no dependence on 5'-terminal 7-methylguanosine was found with either cell-free system. The importance of the 5'-terminal cap for the efficient translation of TMV RNA and globin mRNA increased as the concentration of K+ in a protein-synthesis system was raised. In a reticulocyte lysate analogs and enzymic decapping had a similar effect on translation. In a wheat germ extract, mRNA decapping resulted in a more pronounced decrease of mRNA activity, presumably due to the increased susceptibility of decapped mRNAs to the nucleases present in this protein synthesis system. 3. The requirement for a 5'-terminal cap was similar for the synthesis of 130,000-Mr and 165,000-Mr polypeptides coded by TMV RNA. This indicates that both proteins may be initiated at the common site close to the 5' terminus.

Animals↗
PubMed1994

Expression of mRNA encoding neurotrophins and neurotrophin receptors in rat thymus, spleen tissue and immunocompetent cells. Regulation of neurotrophin-4 mRNA expression by mitogens and leukotriene B4.

The expression of neurotrophin and neurotrophin receptor mRNAs was examined using RNase protection assays and Northern-blot analysis in rat thymus, spleen tissue and immunocompetent mononuclear cells purified from these two organs. Nerve growth factor, brain-derived neurotrophic factor, neurotrophin-3 and neurotrophin-4 mRNAs were all expressed in thymus and spleen tissue although at different levels, while immunocompetent cells expressed neurotrophin-3 and neurotrophin-4 mRNAs. Thymus and spleen tissue expressed mRNAs encoding the low-affinity nerve-growth-factor receptor, the non-neuronal TrkA I receptor, the truncated (kinase deficient) and full-length TrkB, and the TrkC receptor. Low-affinity nerve-growth-factor receptor and non-neuronal TrkA I mRNAs were detected in both thymus and spleen immunocompetent cells. In addition, thymus cells expressed neuronal TrkA II mRNA and spleen cells expressed truncated TrkB mRNA. The expression of TrkA I and TrkA II mRNAs was enhanced in both thymus and spleen cells after cell culture. Enhanced levels of neurotrophin-4 mRNA were observed in spleen immunocompetent cells after adrenalectomy. Moreover, the expression of neurotrophin-4 mRNA was up-regulated after stimulation of immune cells with the mitogens concanavalin A or lipopolysaccharide or with the inflammatory mediator leukotriene B4. This suggests that neurotrophin-4 could be secreted by immunocompetent cells and may be involved in inflammatory processes.

Adrenalectomy↗
PubMed1997

Purification and characterisation of cathepsin B mRNA 3'-untranslated-region-binding protein (CBBP), a protein that represses cathepsin B mRNA translation.

We reported that the 3'-untranslated region (3'-UTR) of cathepsin B mRNA of Sarcophaga peregrina (flesh fly) is necessary for the repression of its translation, and detected the 3'-UTR-binding protein in lysates of larval hemocytes in which cathepsin B mRNA translation was repressed [Yano, T., Kurata, S. & Natori, S. (1995) Eur. J. Biochem. 234, 39-43]. In this study, we purified the 3'-UTR-binding protein from an embryonic cell line of Sarcophaga. The purified protein (CBBP) was found to repress cathepsin B mRNA translation in a rabbit reticulocyte lysate. We found that the CBBP contents of the hemocytes did not change during metamorphosis, although the cathepsin B mRNA became translatable only at the pupal stage. Moreover, we found that pupal, but not larval hemocytes, contained a factor that inhibited the binding of CBBP to the 3'-UTR. A regulatory mechanism of cathepsin B expression in Sarcophaga hemocytes is discussed.

Animals↗
PubMed2003

Helicobacter pylori cag pathogenicity island is associated with reduced expression of interleukin-4 (IL-4) mRNA and modulation of the IL-4delta2 mRNA isoform in human gastric mucosa.

Interleukin-4 (IL-4) and IL-4delta2 mRNA gastric expression was evaluated in healthy subjects and patients who did not have ulcers but were infected with Helicobacter pylori with or without the cag pathogenicity island (cag PAI). IL-4 mRNA was physiologically expressed by gastric epithelium and negatively influenced by H. pylori. Also, nonepithelial cells in the lamina propria of H. pylori-infected patients expressed IL-4 mRNA, whereas IL-4delta2 mRNA was found only in cag PAI-negative patients. Thus, gastric IL-4 takes part in the local immune response to H. pylori.

Adult↗
PubMed1991

Multiple determinants of functional mRNA stability: sequence alterations at either end of the lacZ gene affect the rate of mRNA inactivation.

The Escherichia coli lacZ gene was used as a model system to identify specific sequence elements affecting mRNA stability. Various insertions and substitutions at the ribosome-binding site increased or decreased the rate of mRNA inactivation by up to fourfold. Deletion of a dyad symmetry, which may give rise to a very stable secondary structure in the mRNA immediately downstream of the gene, decreased the functional stability of the lacZ message. The magnitude of the latter effect was strongly dependent on the sequences at the ribosome-binding site, ranging from practically no effect for the most labile transcripts to a threefold decrease in stability for the most stable one. The results suggest that the wild-type lacZ message is inactivated predominantly by attacks near the ribosome-binding site, presumably in part because the putative secondary structure downstream of the gene protects against 3'-exonucleolytic attack. Taken together, the data for all of the modified variants of lacZ were shown to be quantitatively compatible with a general model of mRNA inactivation involving multiple independent target sites.

Base Sequence↗
PubMed2001

Epstein-Barr virus SM protein interacts with mRNA in vivo and mediates a gene-specific increase in cytoplasmic mRNA.

SM is an Epstein-Barr virus (EBV) gene expressed during early lytic replication of EBV. SM encodes a nuclear phosphoprotein that functions as a posttranscriptional regulator of gene expression. SM has been implicated in several aspects of gene regulation, including nuclear mRNA stabilization, posttranscriptional processing, and nuclear mRNA export. Activation by SM is promoter independent but gene specific. The mechanism by which SM selectively activates some EBV target genes or heterologous reporter genes remains to be determined. SM binds RNA in vitro, suggesting that sequence- or structure-specific mRNA interactions might mediate SM specificity. We have further analyzed RNA binding by SM and demonstrated that proteolytic cleavage of SM and consequent exposure of an arginine-rich region are necessary to allow RNA binding in vitro. However, SM mutants with deletions of this arginine-rich region localized normally in the nucleus and were fully functional in gene activation. We therefore developed an assay to study in vivo interactions of SM with target mRNAs based on immunoprecipitation of SM from cell lysates followed by RNase protection analysis. Using this assay, we demonstrated that SM forms complexes with specific mRNAs in vivo. SM binds mRNAs from both SM-responsive as well as nonresponsive intronless genes and increases the nuclear accumulation of both types of mRNAs. In addition, SM preferentially associates with newly transcribed mRNAs. These data indicate that SM forms complexes with mRNAs in the nucleus and enhances their nuclear accumulation. However, SM does not enhance cytoplasmic accumulation of all transcripts that it binds to the same degree, suggesting that additional mRNA-specific characteristics, such as nuclear retention motifs or binding sites for cellular proteins, also determine responsiveness to SM.

Cytoplasm↗
PubMed2000

An AU-rich sequence element (UUUN[A/U]U) downstream of the edited C in apolipoprotein B mRNA is a high-affinity binding site for Apobec-1: binding of Apobec-1 to this motif in the 3' untranslated region of c-myc increases mRNA stability.

Apobec-1, the catalytic subunit of the mammalian apolipoprotein B (apoB) mRNA-editing enzyme, is a cytidine deaminase with RNA binding activity for AU-rich sequences. This RNA binding activity is required for Apobec-1 to mediate C-to-U RNA editing. Filter binding assays, using immobilized Apobec-1, demonstrate saturable binding to a 105-nt apoB RNA with a K(d) of approximately 435 nM. A series of AU-rich templates was used to identify a high-affinity ( approximately 50 nM) binding site of consensus sequence UUUN[A/U]U, with multiple copies of this sequence constituting the high-affinity binding site. In order to determine whether this consensus site could be functionally demonstrated from within an apoB RNA, circular-permutation analysis was performed, revealing one major (UUUGAU) and one minor (UU) site located 3 and 16 nucleotides, respectively, downstream of the edited base. Secondary-structure predictions reveal a stem-loop flanking the edited base with Apobec-1 binding to the consensus site(s) at an open loop. A similar consensus (AUUUA) is present in the 3' untranslated regions of several mRNAs, including that of c-myc, that are known to undergo rapid degradation. In this context, it is presumed that the consensus motif acts as a destabilizing element. As an independent test of the ability of Apobec-1 to bind to this sequence, F442A cells were transfected with Apobec-1 and the half-life of c-myc mRNA was determined following actinomycin D treatment. These studies demonstrated an increase in the half-life of c-myc mRNA from 90 to 240 min in control versus Apobec-1-expressing cells. Apobec-1 expression mutants, in which RNA binding activity is eliminated, failed to alter c-myc mRNA turnover. Taken together, the data establish a consensus binding site for Apobec-1 embedded in proximity to the edited base in apoB RNA. Binding to this site in other target RNAs raises the possibility that Apobec-1 may be involved in other aspects of RNA metabolism, independent of its role as an apoB RNA-specific cytidine deaminase.

3' Untranslated Regions↗
PubMed2001

BSF binds specifically to the bicoid mRNA 3' untranslated region and contributes to stabilization of bicoid mRNA.

The early stages of Drosophila melanogaster development rely extensively on posttranscriptional forms of gene regulation. Deployment of the anterior body patterning morphogen, the Bicoid protein, requires both localization and translational regulation of the maternal bicoid mRNA. Here we provide evidence that the bicoid mRNA is also selectively stabilized during oogenesis. We identify and isolate a protein, BSF, that binds specifically to IV/V RNA, a minimal form of the bicoid mRNA 3' untranslated region that supports a normal program of mRNA localization during oogenesis. Mutations that disrupt the BSF binding site in IV/V RNA or substantially reduce the level of BSF protein lead to reduction in IV/V RNA levels, indicating a role for BSF in RNA stabilization. The BSF protein is novel and lacks all of the characterized RNA binding motifs. However, BSF does include multiple copies of the PPR motif, whose function is unknown but appears in other proteins with roles in RNA metabolism.

Amino Acid Sequence↗
PubMed2002

Developmental control of histone mRNA and dSLBP synthesis during Drosophila embryogenesis and the role of dSLBP in histone mRNA 3' end processing in vivo.

In metazoans, the 3' end of histone mRNA is not polyadenylated but instead ends with a stem-loop structure that is required for cell cycle-regulated expression. The sequence of the stem-loop in the Drosophila melanogaster histone H2b, H3, and H4 genes is identical to the consensus sequence of other metazoan histone mRNAs, but the sequence of the stem-loop in the D. melanogaster histone H2a and H1 genes is novel. dSLBP binds to these novel stem-loop sequences as well as the canonical stem-loop with similar affinity. Eggs derived from females containing a viable, hypomorphic mutation in dSLBP store greatly reduced amounts of all five histone mRNAs in the egg, indicating that dSLBP is required in the maternal germ line for production of each histone mRNA. Embryos deficient in zygotic dSLBP function accumulate poly(A)(+) versions of all five histone mRNAs as a result of usage of polyadenylation signals located 3' of the stem-loop in each histone gene. Since the 3' ends of adjacent histone genes are close together, these polyadenylation signals may ensure the termination of transcription in order to prevent read-through into the next gene, which could possibly disrupt transcription or produce antisense histone mRNA that might trigger RNA interference. During early wild-type embryogenesis, ubiquitous zygotic histone gene transcription is activated at the end of the syncytial nuclear cycles during S phase of cycle 14, silenced during the subsequent G(2) phase, and then reactivated near the end of that G(2) phase in the well-described mitotic domain pattern. There is little or no dSLBP protein provided maternally in wild-type embryos, and zygotic expression of dSLBP is immediately required to process newly made histone pre-mRNA.

Animals↗
PubMed1991

Model system for optimising mRNA non-isotopic in situ hybridisation: riboprobe detection of lysozyme mRNA in archival gut biopsy specimens.

The aim of this study was to optimise conditions for mRNA detection by nonisotopic in situ hybridisation (NISH) using biotinylated and digoxigenin labelled riboprobes. Because lysozyme gene transcripts are present at high concentrations in Paneth and other alimentary cells, archival gut biopsy specimens were chosen as a model system for these experiments. Most of the variables in NISH, from unmasking of mRNA, to its ultimate detection by peroxidase or alkaline phosphatase based detection systems, were examined in detail. The most important findings were that simultaneous heating of tissue targets and riboprobes at 95 degrees C for 15 minutes before hybridisation at 50 degrees C for two hours gave the most intense signal for lysozyme mRNA in Paneth cells, Brunner's glands, and lamina propria macrophages; digoxigenin labelled riboprobes gave a higher signal to noise ratio than their biotinylated counterparts, and probes 600 base pairs long were superior to shorter probes. It is concluded that the mRNA NISH method may be generally useful for detecting gene transcription in archival clinical biopsy specimens.

Archives↗
PubMed1992

Influences of hypothyroidism on TRH concentrations and preproTRH mRNA levels in rat hypothalamus: a simple and reliable method to detect preproTRH mRNA level.

To gain further insight into the regulation of hypothalamic TRH by thyroid hormones, we measured TRH concentration in specific hypothalamic nuclei and preproTRH mRNA levels in the anterior hypothalamus. Adult male rats were decapitated 1, 7, 14 days after thyroidectomy. Micropunches by the method of Palkovitz from seven hypothalamic nuclei and median eminence were used for measurement of TRH by radioimmunoassay. As compared with normal levels, TRH concentration significantly decreased in the median eminence and five hypothalamic nuclei including paraventricular nucleus (PVN), posterior nucleus, anterior nucleus, arcuate nucleus, and ventromedial nucleus pars lateralis, by 7 days after thyroidectomy. No significant changes were observed in dorsomedial nucleus or ventromedial nucleus pars medialis until 14 days after thyroidectomy. A rapid and simple method to detect specific mRNA for preproTRH was developed using the polymerase chain reaction and a single anterior hypothalamic section. PreproTRH mRNA levels in the anterior hypothalamus increased approximately twice 7 days after thyroidectomy. These data indicate that thyroidectomy caused a marked increase in preproTRH mRNA levels of the anterior hypothalamus, while it significantly reduced TRH concentrations not only in PVN and median eminence but also in other specific hypothalamic nuclei, suggesting that these nuclei might be involved in the thyrotropin regulation in the hypothalamus.

Animals↗
PubMed1992

Short-term starvation decreases POMC mRNA but does not alter GnRH mRNA in the brain of adult male rats.

Dietary restriction reduces circulating gonadotropin and testosterone levels in male rats, an effect thought to be mediated through reduced gonadotropin-releasing hormone (GnRH) secretion; however, the cellular mechanisms subserving this response are still unknown. We reasoned that if dietary restriction reduces GnRH secretion, this would be reflected by a decrease in GnRH synthesis and likewise cellular GnRH mRNA levels. We tested this hypothesis by comparing cellular levels of GnRH mRNA between ad libitum fed (n = 4) and starved (n = 4) adult male rats. Five days of starvation resulted in a 21% decrease in body weight and an 85% decline in serum testosterone levels (fed: 13.9 +/- 2.00 vs. starved: 2.1 +/- 0.70 nmol/l; p < 0.01). In situ hybridization and image analysis demonstrated that short-term starvation influenced neither GnRH cell number (fed: 148 +/- 16 vs. starved: 157 +/- 13 cells) nor cellular GnRH mRNA signal level (fed: 177 +/- 5 vs. starved: 160 +/- 7 grains/cell) in any region of the basal forebrain. Endogenous opioid peptides are known to exert an inhibitory effect on GnRH secretion and have been implicated in having a role in the starvation-induced effects on the reproductive system. We therefore also tested the hypothesis that alterations in proopiomelanocortin (POMC) gene expression are involved in the neuroendocrine response to starvation, by comparing cellular POMC mRNA levels in individual neurons (approximately 160 neurons/animal) of the arcuate and periarcuate nuclei between fed control (n = 4) and starved (n = 4) adult male rats.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1996

Localization of basic fibroblast growth factor mRNA (FGF-2 mRNA) in the uterus of mated and unmated gilts.

In mated sows, the level of placental vascularization has a direct effect on fetal growth and litter birth weight. Vascularization of the endometrium and uterus under the control of various polypeptide growth factors is an important early stage in this process. Basic fibroblast growth factor (FGF-2), a polypeptide distributed throughout the mesodermal and neuroectodermal tissues of many species, is a vascular endothelial cell mitogen in vitro and has been implicated in neovascularization and wound healing in vivo. As part of our studies of the distribution of FGF-2 in uterine tissue and its role in placental development and embryo implantation, the localization and changes in the abundance of porcine FGF-2 mRNA in the uterus of mated and unmated gilts were investigated by in situ hybridization procedures. These procedures were based on the use of [alpha35S]-dATP-labeled oligonucleotide probes and a novel set of digoxigenin-labeled oligonucleotide probes generated by reverse transcriptase-polymerase chain reaction (RT-PCR) methods and anti-sense labeling strategies from the corresponding mRNA templates. With these in situ hybridization procedures, porcine FGF-2 mRNA was localized during the first 30 days of pregnancy to specific tissue areas in the porcine uterus comprising glandular and luminal epithelial cells and stromal cells of both the stratum functionalis and stratum basalis regions of the endometrium, and within the smooth muscle of myometrium and the associated blood vessels. However, no significant increase in the level of FGF-2 mRNA within these tissues was detected during these early stages of pregnancy or during the estrous cycle of unmated gilts. These distribution and abundance patterns are only partially compatible with other recent observations suggesting a possible role for changing levels of the mature polypeptide form of FGF-2 in the reproductive tract of sows during the early stages of pregnancy.

Animals↗
PubMed1992

Hypotensive hemorrhage elevates corticotropin-releasing hormone messenger ribonucleic acid (mRNA) but not vasopressin mRNA in the rat hypothalamus.

We examined the effect of acute hypotensive hemorrhage on corticotropin-releasing hormone (CRH) and arginine vasopressin (AVP) messenger RNAs (mRNAs) in neurons of the rat hypothalamus. Sprague-Dawley male rats were cannulated (femoral artery and vein) and received a 15 ml/kg.3 min hemorrhage on the morning of the fourth day. Time controls received no hemorrhage. After light halothane anesthesia, the rats were decapitated at 1 or 4 h (six to nine rats per group). The hypothalami were removed, frozen, and sectioned at 12 microns. In situ hybridization was performed using two 48-base oligodeoxynucleotide probes for CRH and AVP message, respectively. Hemorrhage led to a fall in arterial blood pressure and heart rate that recovered by 1 h. Plasma ACTH, corticosterone, and AVP were elevated 20, 60, and 90 min after hemorrhage, but returned to near control levels by 4 h. CRH mRNA was significantly elevated 1 and 4 h after hemorrhage, as compared to time controls, in parvocellular neurons of the paraventricular nuclei. However, AVP mRNA was not different from controls at 1 or 4 h after hemorrhage in the magnocellular or parvocellular paraventricular nuclei, or in the supraoptic or accessory nuclei of the hypothalamus. AVP mRNA was also found in neurons of the suprachiasmatic nuclei, but there was no difference in the amount of mRNA between the 1-h hemorrhage and control groups. These data suggest that neural signals, originating for cardiovascular receptors activated by hemorrhage, up-regulate message for CRH but not for AVP in the paraventricular nuclei of the rat hypothalamus.

Adrenocorticotropic Hormone↗