Biomedical subjects

E Normand

Publications and source records attributed to E Normand.

At least 19 recordsLinked to original sources

PubMed1998

Opioid receptor gene expression in the rat brain during ontogeny, with special reference to the mesostriatal system: an in situ hybridization study.

The three main types of opioid receptors micro, delta and kappa are found in the central nervous system and periphery. In situ hybridization study was undertaken to determine the expression of mu, delta, kappa-opioid receptors mRNAs in the brain during pre- and postnatal development, especially in the mesostriatal system. By G13, mu and kappa-opioid receptor mRNA were detectable in the telencephalon; mu-opioid receptor mRNA was found in the striatal neuroepithelium and cortical plate and kappa-opioid receptor mRNA in the corroidal fissure. By G15, kappa-opioid receptor mRNA was detectable in the nucleus accumbens and dorsal striatum, and in the substantia nigra and ventral tegmental area, suggesting an early expression of the corresponding receptor on dopaminergic terminal fibers. For the mu-opioid receptor mRNA in the striatum, patches appeared at G20. Delta-opioid receptor mRNA was first detected at G21, in many areas including the accumbens nucleus and the dorsal striatum. At P8, delta-opioid receptor mRNA was detected in large-sized cells of the striatum, possibly cholinergic, suggesting a possible modulation by opioids of the striatal cholinergic neurons. Our results demonstrate the early appearance of mu and kappa-opioid receptor mRNA (G13) and the relatively late development of delta-opioid receptor mRNA (G21) in the brain. We also show a distinct pattern of expression for mu, delta and kappa-opioid receptor mRNAs in the mesostriatal system during the development.

Animals↗

PubMed1995

Effect of reserpine treatment on enkephalin mRNA level in the rat striatum: an in situ hybridization study.

We investigated the molecular mechanisms responsible for the preproenkephalin A mRNA increase following catecholamine depletion by reserpine using quantitative in situ hybridization at the cellular level. Macroscopic analysis showed that short term reserpine treatment increases the preproenkephalin A mRNA level in the rat striatum to +40.2 +/- 9%. Microautoradiography analysis demonstrated different increases in the preproenkephalin A mRNA level in different parts of the striatum: +124 +/- 22% in the dorso-median striatum, +131 +/- 19% in the dorso-lateral striatum, +119 +/- 8% in the ventro-lateral striatum and +75 +/- 6% in the ventro-median striatum. We found no difference in the number of cells expressing PPA mRNA in reserpine treated rats suggesting that these increases are only due to an increase in the number of mRNA expressed by cell.

Animals↗

PubMed1995

Acute and chronic amphetamine treatments differently regulate neuropeptide messenger RNA levels and Fos immunoreactivity in rat striatal neurons.

Repeated administration of amphetamine results in the well known phenomenon of reverse tolerance or sensitization. However, little is known about cellular and molecular mechanisms underlying acute versus chronic response to amphetamine. In this paper, we investigated the effects of acute (1.5 or 5 mg/kg) and chronic (5 mg/kg/day for 14 days) amphetamine treatment on locomotor activity, stereotypy, Fos immunoreactivity and messenger RNA levels of molecules implicated in dopamine transmission in the rat striatum and substantia nigra. In agreement with other studies, acute amphetamine induced a dose dependent increase in locomotor activity and stereotypy. Also, a comparison between the behavior observed after the first injection and the last injection of amphetamine in chronically treated rats showed sensitization as demonstrated by a higher rating of stereotypy. We have found that acute and chronic amphetamine treatments differently modulate the activity of several output neurons. A double labeling procedure with Fos immunohistochemistry coupled with in situ hybridization demonstrated that acute amphetamine treatment induces Fos immunoreactivity predominantly in striatal neurons expressing substance P messenger RNA (77.07 +/- 1.42%). Only 32.6 +/- 2.07% of Fos immunoreactive neurons expressed preproenkephalin A messenger RNA. In chronic amphetamine treated rats, 56.21 +/- 1.32% of the Fos immunoreactive neurons expressed substance P messenger RNA while 52.12 +/- 1.84% expressed preproenkephalin A messenger RNA. Statistical analysis revealed that this difference is mainly due to a decrease in the density of substance P immunoreactive neurons in chronically treated rats in comparison to acute. Amphetamine treatments induced Fos immunoreactivity in the substantia nigra in non-dopamine neurons. As measured by quantitative in situ hybridization, acute amphetamine induced an increase in substance P, preproenkephalin A and dynorphin messenger RNA levels (+23 +/- 0.05%, +45 +/- 0.07% and +24 +/- 0.05%, respectively). No difference in these increases was observed in relation with the dose injected (1.5 or 5 mg/kg). Chronic amphetamine treatment enhanced only substance P and dynorphin messenger RNA levels (+23 +/- 0.04% and +42 +/- 0.04%, respectively). Neither acute nor chronic amphetamine treatment had any effects on D1 or D2 dopamine receptor messenger RNA levels. Our main conclusions are: (1) in acutely treated rats Fos is essentially expressed by substance P neurons; (2) in chronically treated rats, Fos immunoreactivity is expressed by the two efferent striatal populations (i.e. preproenkephalin A and substance P neurons) and the number of Fos immunoreactive neurons is reduced as compared with acute; (3) neuropeptide messenger RNA levels, but not dopamine receptor messenger RNAs, are affected in the response to acute or chronic treatment with amphetamine.

Amphetamine↗

PubMed1995

[Midazolam versus placebo before spinal anesthesia].

The goal of this randomized, double blind and multicentric study was to compare the effects of midazolam (M) and placebo (P) administered by titration before puncture for spinal anaesthesia on the comfort of 211 patients scheduled for elective surgery after oral premedication with hydroxyzine. The administered dose of midazolam was 3.4 +/- 1.3 mg (mean +/- SD). Anxiety was nil in 92% of the patients of the M group and in 64% of the patients of the P group (p < 0.001) and memorization of the pain of the puncture was reported in 34% of the patients of the M group and in 66% of the patients of the P group (p < 0.001). However cooperation of the patient and easiness of the puncture were similar in both groups. In conclusion titrated sedation with midazolam before puncture for spinal anaesthesia increases the comfort of the patient.

Adjuvants, Anesthesia↗

PubMed1995

Use of non-radioactive probes for mRNA detection by in situ hybridization: interests and applications in the central nervous system.

Non-radioactive probes for in situ hybridization (ISH) are now widely used to detect mRNAs in the central nervous system (CNS) using light and electron microscopy. Many different protocols for the detection of biotinylated or digoxigenin-labelled probes are now available. The advantages and inconveniences of the use of the non-radioactive probes are reviewed in the current work. These aspects are illustrated by some results from first-hand experience in the field of ISH to analyse gene expression and neuronal phenotypes in the hypothalamus and the basal ganglia. A very sensitive procedure for the simultaneous detection of two mRNAs with cRNA probes have been detailed and using in particular digoxigenin-labelled probes.

Animals↗

PubMed1994

Prenatal ontogeny of D2 dopamine receptor and dopamine transporter gene expression in the rat mesencephalon.

This work demonstrates the early prenatal expression (by gestational day 14) of dopamine D2 receptor and dopamine transporter mRNAs by immature dopaminergic cells of the rat mesencephalon using in situ hybridization. Our results indicate that mRNAs are detectable 3 days before the appearance of functional D2 presynaptic receptors and detectable dopamine release at striatal terminals.

Animals↗

PubMed1994

Completeness of prescription recording in outpatient medical records from a health maintenance organization.

Since validity of drug data is often characterized by the agreement between questionnaire and medical record data, medical record completeness for drug therapy was evaluated. Outpatient medical records of 501 randomly selected Group Health Cooperative Health Maintenance Organization (HMO) participants known to have been dispensed a non-steroidal anti-inflammatory drug (NSAID) were reviewed for completeness. Documentation was also evaluated for indication, age, gender, location of visit, and number of visits. The NSAID was recorded in 89% of the charts reviewed. Charts with a vague/missing diagnosis were more likely to lack documentation [RR (95% CI): 20.0 (13.2-30.3)]. The data suggested that poorer documentation was related to older age [1.5 (0.9-2.5)] but not to gender, indication, location of visit, or number of visits. Presence of an indication was positively correlated to the completeness of drug documentation. According to this staff/group HMO, there may be a higher concordance between self-reported medication use and medical record data than found in previous literature.

Age Factors↗

PubMed1993

Tumor necrosis factor alpha in human kidney transplant rejection--analysis by in situ hybridization.

Macrophagic infiltration and necrosis of rejected kidney transplants represent two pejorative patterns. It has been assumed that the macrophagic toxicity is mediated partly by secretion of tumor necrosis factor alpha. On the other hand, TNF is also involved in many inflammatory and immunological phenomena. We thus evaluated the expression of TNF mRNA by in situ hybridization in 6 rejected kidney transplants using a radiolabeled TNF-c DNA probe. Then the synthesis of TNF alpha protein was studied by immunohistochemistry using an anti-TNF alpha antibody. In severely rejected kidney grafts, TNF mRNA is expressed in some monomorphic infiltrating cells, mostly located in the deepest part of the cortex and around the tubes. These cells do not bind other probes, such as dopa-decarboxylase DNA or preproenkephalin RNA. They are also recognized by a monoclonal antibody directed against TNF alpha. What is more, this antibody binds with some glomerular endothelial and tubular epithelial cells that do not express TNF mRNA. These cells are likely target cells for TNF. In the normal kidney, there are no cells expressing TNF-alpha mRNA.

Gene Expression↗

PubMed1992

Expression of the HBNF (heparin-binding neurite-promoting factor) gene in the brain of fetal, neonatal and adult rat: an in situ hybridization study.

HBNF (heparin-binding neurite-promoting factor) and MK (midkine) are members of a newly recognized family of proteins, the expression of which is developmentally regulated. These proteins are expressed highest during fetal development in many tissues but they seem to be rather restricted to the brain in adult animals. Gene expression for these proteins is inducible by retinoic acid in embryonal carcinoma cell lines. They induce neurite outgrowth in cultured neurons, and they are characterized by high sequence conservation between species. While the function(s) of these proteins are unknown, available evidence suggests possible roles in the development and the maintenance of neural tissues. This in situ hybridization study investigates the temporal and spatial expression pattern of the HBNF gene in the brain of developing rats. The HBNF gene is highly expressed in the neuroepithelium and the ependyma from fetal day 15 on. Although most ependymal structures express the gene strongly, a few restricted areas of the ependyma do not express HBNF (ventral part of the fourth ventricle, subcommissural organ). In the brain parenchyma, HBNF is expressed in the thalamo-hippocampal area from fetal day 15 and in the cerebral cortex from fetal day 16, with high expression occurring in the superficial layers of the cortex. The nature of the cells expressing the gene, while difficult to ascertain, is probably glial for the most part. However, certain neurons (in limited areas of the brain parenchyma) and most pial cells (in the meninges), also express the gene. HBNF gene expression decreases sharply a few days after birth. HBNF mRNA is also detectable at fetal days 15 and 16 in the face fetal mesenchyma. In the adult rat brain, the expression of the HBNF gene appears to be restricted to neurons of the hippocampus and of the olfactory bulb and to the superficial layers of the cortex. The structurally related MK gene, though not extensively studied here, shows an entirely different temporal and spatial expression pattern. MK gene is weakly expressed during ontogeny in most brain areas, and in the adult animal, MK mRNA is present only in the choroid plexus. The intense and widely distributed expression of the HBNF gene in several cell populations in the fetus, the progressive spatial and quantitative restriction of HBNF gene expression with brain differentiation, as well as the properties of the protein suggest important and diverse functions for HBNF in cellular interactions and cell differentiation in the developing brain, that must act temporally and spatially by ways distinct from its MK companion molecule.

Amino Acid Sequence↗

PubMed1992

Growth hormone-releasing hormone-synthesizing neurons are a subpopulation of somatostatin receptor-labelled cells in the rat arcuate nucleus: a combined in situ hybridization and receptor light-microscopic radioautographic study.

Distribution of growth-hormone-releasing hormone (GHRH) cell bodies and somatostatin binding sites were compared in the mediobasal hypothalamus of the rat. GHRH-synthesizing neurons were visualized by in situ hybridization, using as 35S-labelled synthetic oligonucleotide (45 mere), and 125I-Tyr0-DTrp8-somatostatin (125I-SRIH) binding sites by light-microscopic radioautography on adjacent 20-microns-thick frozen mirror sections. GHRH mRNA hybridizing cells were detected mostly in the ventrolateral portion of the arcuate nucleus (ARC) and around the perimeter of the ventromedial nucleus (VMN). Comparison with the distribution of pericellular 125I-SRIH binding sites allowed to differentiate three types of cells: (1) GHRH perikarya not associated with pericellular 125I-SRIH binding sites around the perimeter of the VMN, (2) 125I-SRIH-labelled cells, not associated with GHRH perikarya in the periventricular zone along the dorsal part of the third ventricle, and (3) in the ventrolateral portion of the ARC, GHRH mRNA-labelled neurons had the same distribution as 125I-SRIH-labelled cells. Furthermore, on adjacent sections, the number of both labelled cells were correlated (r = 0.68; p less than 0.001). In this last population, the extent of colocalization of 125I-SRIH binding sites on GHRH mRNA-labelled neurons was further investigated in adjacent 5-microns-thick sections. The proportions of cells GHRH mRNA and 125I-SRIH allowed to differentiate three subdivisions of the arcuate: the periventricular (PV), ventrobasal (VB) and lateral portions. In the PV-ARC, 27% of GHRH-synthesizing cells were coidentified as 125I-labelled while only 6% of 125I-labelled cells contained GHRH mRNA. In the VB-ARC the proportion of double-labelled cells was equivalent (31 and 26%, respectively for GHRH mRNA and 125I-SRIH).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1992

Phenotypical characterization of the rat striatal neurons expressing muscarinic receptor genes.

Neurons expressing the m1, m2, and m4 muscarinic receptor genes in the adult rat striatum were identified and characterized by using several in situ hybridization and immunohistochemical procedures. Combined in situ hybridization for the simultaneous detection of two mRNAs in the same section or in adjacent sections as well as in situ hybridization and immunohistochemistry on adjacent sections permitted us to identify the neurons containing m1, m2, or m4 receptor mRNA. Our observations demonstrate that m1, m2, and m4 receptor genes are expressed in one or several phenotypically distinct neuronal populations. The m1 receptor gene was the most widely expressed (85% of the striatal neurons). Most cholinergic neurons (80% or more) contain m1, m2, and m4 receptor mRNAs. Almost all the substance P neurons contain m1 and m4 receptor mRNA. All enkephalinergic neurons contained m1 receptor mRNA, but only 39% contained m4 receptor mRNA. Most somatostatin and neurotensin neurons expressed the m1 receptor gene, but only a few (15% and 9%, respectively) contained m4 receptor mRNA. The present study offers anatomical evidence that ACh may act directly in complex ways on the main neuronal populations of the striatum through muscarinic receptors. The m1, m2, and m4 receptors may act as autoreceptors to control ACh release and possibly other parameters of ACh neurons. On the other hand, the m1 and m4 receptors may act as heteroreceptors in cholinoceptive efferent neurons (enkephalin and substance P neurons) and other neurons (somatostatin/neuropeptide Y and neurotensin neurons). The presence of m4 receptor mRNA in only parts of the enkephalin, somatostatin, and neurotensin neuronal populations indicates that muscarinic receptor gene expression contributes to the functional and anatomical heterogeneity of the striatum that may relate to higher order of organization, including patch-matrix compartmentalization. The wide expression of m1 and m4 receptor genes in the striatum suggests that ACh may directly influence neurotransmitter release and synthesis in striatal efferent and intrinsic neurons. Our results imply that the specific pattern of expression of the muscarinic receptor genes mediates direct effects of ACh on activities and functions of chemically and topologically defined striatal neuronal populations. Since the expression of muscarinic receptors occurred in the three main neuronal populations of the striatum, namely ACh, enkephalins, and substance P neurons that also express dopamine receptors, it is highly probable that ACh and dopamine may act together at the single-cell level to influence striatal functions.

Animals↗

PubMed1991

[Tumor necrosis factor in graft rejection. In situ hybridization study].

The development of necrosis and macrophage infiltration increases the risk of renal graft rejection. But the macrophages secrete the alpha form of the tumour necrosing factor (TNF) which is also involved in several immunologic and inflammatory phenomena. We therefore studied the expression of the gene TNF alpha by in situ hybridization during advanced stage rejection after renal transplantation: the grafts were infiltrated with macrophage-like cells expressing the mRNA of the TNF alpha gene, particularly deep in the cortex and in the medulla. These cells then secrete the TNF alpha molecule since they are recognized by anti-TNF alpha antibodies. These antibodies also recognize certain other glomerular endothelial and tubular epithelial cells which do not express the TNF alpha gene: these cells are undoubtedly the TNF target cells. These findings confirm the synthesis of TNF alpha in advanced stage renal graft rejection.

Colorectal Neoplasms↗

PubMed1991

Aromatic L-amino-acid decarboxylase (DOPA decarboxylase) gene expression in dopaminergic and serotoninergic cells of the rat brainstem.

In situ hybridization was performed in the rat brain to detect aromatic L-amino acid decarboxylase (AADC) mRNA using 35S-labeled oligonucleotide probes derived from rat kidney AADC cDNA. Results demonstrated AADC mRNA in areas containing dopaminergic and serotoninergic cell bodies. Combined immunohistochemistry for tyrosine- or tryptophan hydroxylase and in situ hybridization for AADC mRNA demonstrated the dopaminergic or serotoninergic nature of cells containing AADC mRNA. Tyrosine hydroxylase-positive mesencephalic neurons containing a very low or no AADC mRNA signal were also observed.

5-Hydroxytryptophan↗

PubMed1991

Phenotypical characterization of the rat striatal neurons expressing the D1 dopamine receptor gene.

In situ hybridization experiments were performed in rat brain sections from normal and 6-hydroxydopamine-treated rats in order to map and identify the neurons expressing the D1 receptor gene in the striatum and the substantia nigra. Procedures of combined in situ hybridization, allowing the simultaneous detection of two mRNAs in the same section or in adjacent sections, were used to characterize the phenotypes of the neurons expressing the D1 receptor gene. D1 receptor mRNA was found in neurons all over the caudate-putamen, the accumbens nucleus, and the olfactory tubercle but not in the substantia nigra. In the caudate-putamen and accumbens nucleus, most of the neurons containing D1 receptor mRNA were characterized as medium-sized substance P neurons and distinct from those containing D2 receptor mRNA. Nevertheless, 15-20% of the substance P neurons did not contain D1 receptor mRNA. The neurons containing preproenkephalin A mRNA did not contain D1 receptor mRNA but contained D2 receptor mRNA. A small number of cholinergic and somatostatinergic neurons exhibited a weak reaction for D1 receptor mRNA. These results demonstrate that dopamine acts on efferent striatal neurons through expression of distinct receptors--namely, D1 and D2 in separate cell populations (substance P and preproenkephalin A neurons, respectively)--and can also act on nonprojecting neurons through D1 receptor expression.

Animals↗

PubMed1991

Simultaneous detection of two messenger RNAs in the central nervous system: a simple two-step in situ hybridization procedure using a combination of radioactive and non-radioactive probes.

We present here a method enabling the simultaneous detection of two messenger RNAs in tissue sections by use of a two-step in situ hybridization procedure. Tissue sections were hybridized with a radioactive probe and coated with emulsion. The emulsion was processed for development, fixed, and a second hybridization was performed through the emulsion with a biotinylated probe subsequently revealed with streptavidin-alkaline phosphatase. This procedure allows the detection of two mRNAs without loss of signal, removal of the emulsion, or spurious reaction. The simultaneous detection of oxytocin and vasopressin mRNAs in the hypothalamus, and of dopamine receptor and neuropeptide mRNAs in the striatum, demonstrated the efficiency of the procedure. Such a two-step procedure provides a simple and flexible way to make possible comparative analysis of the localization of two mRNAs within the same tissue section.

Animals↗

PubMed1990

Presence of neuropeptide messenger RNAs in neuronal processes.

The messenger RNAs coding for vasopressin, oxytocin, luteinizing hormone releasing-hormone and somatostatin have been detected in tissue sections of the rat brain, especially in the hypothalamus with radioactive and biotinylated oligonucleotide probes. The results demonstrate that neuropeptide mRNAs are present in the cytoplasm of cell bodies, in processes and in punctate structures in the vicinity of the cell bodies. These results demonstrate that neuropeptide mRNAs can be transported outside the cell body most probably in proximal dendrites but also in some of their branching, and possibly at synaptic contacts. These data suggest that neuropeptide mRNA could undergo a specific compartmentation that could contribute to the targetting of the corresponding peptide inside neurons.

Animals↗

PubMed1990

Dopamine receptor gene expression by enkephalin neurons in rat forebrain.

In situ hybridization experiments were performed with brain sections from normal, control and haloperidol-treated rats to identify and map the cells expressing the D2 dopamine receptor gene. D2 receptor mRNA was detected with radioactive or biotinylated oligonucleotide probes. D2 receptor mRNA was present in glandular cells of the pituitary intermediate lobe and in neurons of the substantia nigra, ventral tegmental area, and forebrain, especially in caudate putamen, nucleus accumbens, olfactory tubercle, and piriform cortex. Hybridization with D2 and preproenkephalin A probes in adjacent sections, as well as combined hybridization with the two probes in the same sections, demonstrated that all detectable enkephalin neurons in the striatum contained the D2 receptor mRNA. Large neurons in caudate putamen, which were unlabeled with the preproenkephalin A probe and which may have been cholinergic, also expressed the D2 receptor gene. Haloperidol treatment (14 or 21 days) provoked an increase in mRNA content for D2 receptor and preproenkephalin A in the striatum. This suggests that the increase in D2 receptor number observed after haloperidol treatment is due to increased activity of the D2 gene. These results indicate that in the striatum, the enkephalin neurons are direct targets for dopamine liberated from mesostriatal neurons.

Animals↗

PubMed1989

Distribution of CCK mRNA in particular regions (hippocampus, periaqueductal grey and thalamus) of the rat by in situ hybridization.

Cholecystokinin (CCK) mRNA was detected by in situ hybridization at high magnification in some rat brain regions where CCK octapeptide (CCK-8) is thought to produce its pharmacological effects. The labeling of the dentate gyrus and the sparse but intensively stained cells found in the CA1 layer, stratum radiatum and hilus could correspond to interneurons involved in hippocampal neural activity, in agreement with excitatory responses induced by local injection of CCK-8. The intense labeling of the Edinger-Westphal nucleus and more generally the presence of CCK mRNA in the periaqueductal gray and thalamus ventrobasal nuclei could account for the various effects of CCK in pain transmission.

Animals↗