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1.
Anna Maria Deiana Angelo Cau Susanna Salvadori Elisabetta Coluccia Rita Cannas Angela Milia James Tagliavini 《Chromosome research》2000,8(3):213-218
Major and 5S ribosomal genes have been localized in the chromosomes of Micropterus salmoides. By C-banding, Ag-staining, CMA3-staining and 45S and 5S fluorescence in-situ hybridization (FISH), we demonstrate that the 45S and 5S ribosomal genes are clustered in two different chromosome pairs
and both are located in heterochromatic GC-rich regions. PCR amplification and sequencing of the 5S intergenic non-transcribed
sequences have allowed us to identify variability essentially due to a trinucleotide tandem repeat (GCT).
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
2.
Chromosomal Localization of 5S rDNA Genes in Leporinus Fish (Anostomidae, Characiformes) 总被引:2,自引:0,他引:2
The large 45S rDNA chromosome sites have often been analyzed in fish. In contrast, little is known about the 5S genes in this animal group. In the genus Leporinus, the NOR chromosomal location has been shown to be very diverse. In the present work, chromosome mapping of 5S rDNA in three anostomids, Leporinus elongatus, L. obtusidens and L. friderici, is investigated using fluorescence in-situ hybridization (FISH) with PCR-obtained 5S probes and primed in-situ labeling (PRINS). Major 5S rDNA chromosomal sites were found to be subterminally located in a small metacentric pair, while minor ones were detected near the centromeric region of a medium-sized submetacentric pair in all studied species. The 5S rDNA genes were not associated with the NORs or sex chromosomes. A highly conserved chromosomal location of these genes appears to characterize the karyotype evolution of this fish group. 相似文献
3.
E. Vollmer J. Brust A. Roessner A. Bosse F. Burwikel B. Kaesberg B. Harrach H. Robenek W. Böcker 《Virchows Archiv : an international journal of pathology》1991,419(2):79-88
Summary Atherosclerotic vessels were analysed histochemically for distribution, quantity, and composition of apolipoprotein (Apo) types in the vascular wall. The specimens comprised all stages of atherosclerosis, from very discrete intimal changes to complicated lesions. The vessel specimens were marked with antibodies against human Apo A1, A2, and B. Apo A1 can be demonstrated in even the earliest stage of atherosclerosis, and increases with the progression of the disease. In the initial stage, Apo A1 is found first in lumen-adjacent layers of the intima, and is evident in deeper layers of the wall as the disease progresses. Arteries of muscular type show accumulation of Apo in an earlier stage (or in greater quantity at the same stage) than arteries of elastic type. At all stages, the amount of Apo A1 always exceeds that of A2 and B. In the intima, Apo B is higher than Apo A2, the media contains hardly any Apo B, and the adventitia has less B than A2. Within the intimal layer, Apo A1 and A2 are found in an intracellular (mainly in foam cells) or in an extracellular location, according to the stage of atherosclerosis. Apo B is almost exclusively extracellular; only cases of advanced atherosclerosis show some intracellular localization (mostly in foam cells), visualized as electron dense lamellar organelles, probably of lysosomal origin. In the media, Apo A1 and A2 are accumulated in intracellular deposits, whereas the extracellular storage of Apo A1 A2 and B is observed only in cases with the most severe damage. Our investigations suggest that the accumulation of apolipoproteins in the vascular wall is effected not only by insudation from the plasma, but also by neosynthesis and/or metabolism by locally derived cells or cells immigrating in the process of atherosclerosis. The presence of Apo A1 and A2 in the vessel wall is now documented, and their role at this site apparently differs from that in the plasma.Dedicated to Professor E. Grundmann on the occasion of his 70th birthday. 相似文献
4.
A biotinylated 28S rDNA probe was prepared from the genomic DNA of the Antarctic ice-fishChampsocephalus gunnari and hybridized to metaphase chromosomes of the same species by fluorescencein situ hybridization (FISH). The hybridization signal appeared over the whole heterochromatic arm of the submetacentric chromosomes bearing the nucleolar organizer regions. The results of rDNA/FISH are compared with those coming from classical cytogenetic (C, Q, Ag-NOR, chromomycin A3) banding techniques. Thein situ detection of a specific DNA sequence offers a new more precise perspective for understanding the evolving process in chromosomes of Antarctic fish and will provide an interesting contribution to comparative cytogenetics of lower vertebrates.accepted for publication by M. Schmid 相似文献
5.
GABA is a major neurotransmitter in the hypothalamus. In particular, neurons in the paraventricular nucleus (PVN) of the hypothalamus receive dense GABAergic inputs from peri-PVN regions. The noradrenergic system has been reported as a modulator of GABAergic transmission to the PVN. Previous electrophysiological and morphological studies support the presence of adrenoceptors on GABAergic neurons innervating the PVN. In this study, we identified three adrenoceptors on GABAergic neurons in the peri-PVN region, focusing on the anterior hypothalamic area (AHA) and rostral zona incerta (ZIr). GABAergic neurons were identified using enhanced green fluorescent protein (eGFP), followed by single cell RT-PCR analysis of the GABA synthetic enzymes, glutamic acid decarboxylase (GAD)65 and/or GAD67. Single cell RT-PCR data revealed the expression of alpha(1A)-, alpha(1B)- and alpha(2A)-adrenoceptor mRNA on GABAergic neurons in AHA and ZIr. Additionally, immunohistochemical studies showed that the immunoreactivities of alpha(1A)-, alpha(1B)- and alpha(2A)-adrenoceptor were colocalized with eGFP-expressing neurons in AHA and ZIr. The present findings suggest the contribution of adrenoceptors to the modulation of GABAergic neurons in AHA and ZIr. 相似文献
6.
7.
Among serotonin (5-HT) receptors, the 5-HT3 receptor is the only ligand-gated ion-channel. Little is known about the interaction between the 5-HT3 receptor and other 5-HT receptors and influence of 5-HT3 chronic activation on other 5-HT receptors and the expression of key genes of 5-HT system. Chronic activation of 5-HT3 receptor with intracerebroventricularly administrated selective agonist 1-(3-chlorophenyl)biguanide hydrochloride (m-CPBG) (14 days, 40 nmol, i.c.v.) produced significant desensitization of 5-HT3 and 5-HT1A receptors. The hypothermic responses produced by acute administration of selective agonist of 5-HT3 receptor (m-CPBG, 40 nmol, i.c.v.) or selective agonist of 5-HT1A receptor (8-hydroxy-2-(di-n-propylamino)tetralin) (8-OH-DPAT, 1 mg/kg, i.p.) was significantly lower in m-CPBG treated mice compared with the mice of control groups. Chronic m-CPBG administration failed to induce any significant change in the 5-HT2A receptor functional activity and in the expression of the gene encoding 5-HT2A receptor. Chronic activation of 5-HT3 receptor produced no considerable effect on the expression on 5-HT3, 5-HT1A, and 5-HT transporter (5-HTT) and tryptophan hydroxylase-2 (TPH-2) genes – the key genes of brain 5-HT system, in the midbrain, frontal cortex and hippocampus. In conclusion, chronic activation of ionotropic 5-HT3 receptor produced significant desensitization of 5-HT3 and postsynaptic 5-HT1A receptors but caused no considerable changes in the expression of key genes of the brain 5-HT system. 相似文献
8.
9.
Edwige Dunn Jean-Marc Fritschy Donald B. Carter Kalpana M. Merchant 《Neuroscience letters》1996,210(3):213
A detailed mapping of the γ-aminobutyric acid (GABA)A receptor subunits (α1, α2, α3 and β2+3) in the infralimbic/ventral prelimbic region (IL/vPL) of the rat frontal cortex was carried out using subunit-specific antibodies. The α1 and β2+3 subunit antibodies immunostained all layers of the IL/vPL region. Layers II and III displayed immunostaining of cell bodies whereas I, V and VI showed predominantly neuropil staining. The size of the α1-positive cell bodies corresponded to that of small interneurons (range, 20–55 μm2; mean ± SEM, 37 ± 5.5 μm2) as well as pyramidal cells or large interneurons (range, 87–135 μm2; mean ± SEM, 103.4 ± 9.7 μm2). However, β2+3 antibody immunostained only small cell bodies. Immunoreactivity for α2 was restricted to layers I and II, whereas α3 and α5 subunit expression was seen only in layer VI. The antibody to the α2 subunit immunostained small cell bodies (range, 29–63 μm2; mean ± SEM, 32 ± 4.5 μm2) in layer II, resembling interneurons. Conversely, both α3 and α5 antibodies immunostained large cell bodies (range, 94–151 gmm2; mean ± SEM, 115.7 ± 13.4 μm2), consistent with pyramidal cell labelling in layer VI. 相似文献
10.
Although there is evidence that reduced inhibition in the spinal dorsal horn contributes to neuropathic pain, the mechanisms that underlie this are poorly understood. We have previously demonstrated that there is no loss of neurons from laminae I-III in the spared nerve injury (SNI) model [Polgár E, Hughes DI, Arham AZ, Todd AJ (2005) Loss of neurons from laminas I-III of the spinal dorsal horn is not required for development of tactile allodynia in the SNI model of neuropathic pain. J Neurosci 25:6658-6666]. In this study we investigated whether there was a difference between ipsilateral and contralateral sides in the levels of GABA, the vesicular GABA transporter (VGAT), or the beta(3) subunit of the GABA(A) receptor at synapses in the medial part of the superficial dorsal horn in this model. Tissue from rats that had undergone SNI 4 weeks previously was examined with an electron microscopic immunogold method to reveal GABA, following pre-embedding detection of GABA(A) beta(3) to allow identification of GABAergic terminals. Assessment of labeling for the GABA(A) beta(3) subunit and VGAT was performed by using immunofluorescence and confocal microscopy. We found no difference in the intensity of immunolabeling for any of these markers on the two sides of the superficial dorsal horn. These results suggest that there is no significant loss of GABAergic boutons from the denervated area after SNI (which is consistent with the finding that neuronal death does not occur in this model) and that there is no depletion of GABA or GABA(A) receptors at GABAergic synapses within this region. An alternative explanation for disinhibition after nerve injury is that it results from reduced excitatory drive to GABAergic dorsal horn neurons following loss of primary afferent input to these cells. 相似文献
11.
Hongjun Ma Fulu Gao Lin Sun Chunji Jin Tetsuji Nagata 《Medical Electron Microscopy》1994,27(3-4):352-354
The syntheses of DNA, RNA and protein in the livers of aging mice was studied by electron microscopic radioautography using
radioactive precursors. Labeling with3H-thymidine was observed in the nuclei of some hepatocytes at various prenatal and postnatal ages. The percentage of labeled
cells decreased after birth, then slowly fell to the lowest value at 2 years. The silver grains with3H-uridine labeling were observed in both the nuclei and cytoplasm of hepatocytes at various ages. There was a peak in uridine
labeling at 14 days, and then it slowly decreased until old age. The number of silver grains with3H-leucine labeling in the cytoplasm of hepatocytes was small. It increased after birth, reached the maximum at 1 month, and
continued to decrease with aging. 相似文献
12.
Pawe? Burchardt Jakub ?urawski Bartosz Zuchowski Tomasz Kubacki Dawid Murawa Krzysztof Wiktorowicz Henryk Wysocki 《Archives of Medical Science》2013,9(1):151-158
An increased level of low-density lipoprotein (LDL) is a very well established risk factor of coronary artery disease (CAD). Unoxidized LDL is an inert transport vehicle of cholesterol and other lipids in the body and is thought to be atherogenic. Recently it has been appreciated that oxidized products of LDL are responsible for plaque formation properties previously attributed to the intact particle. The goal of this article is to review the recent understanding of the LDL oxidation pathway. The role of oxidized products and key enzymes (lipoprotein-associated phospholipase A2 and carboxyl ester lipase) are also extensively discussed in the context of clinical conditions. 相似文献
13.
The Tottering (cacna1a(tg)) mouse arose as a consequence of a spontaneous mutation in cacna1a, the gene encoding the pore-forming subunit of the pre-synaptic P/Q-type voltage-gated calcium channel (VGCC, Ca(V)2.1). The mouse phenotype includes ataxia and intermittent myoclonic seizures which have been attributed to impaired excitatory neurotransmission at cerebellar granule cell (CGC) parallel fiber-Purkinje cell (PF-PC) synapses [Zhou YD, Turner TJ, Dunlap K (2003) Enhanced G-protein-dependent modulation of excitatory synaptic transmission in the cerebellum of the Ca(2+)-channel mutant mouse, tottering. J Physiol 547:497-507]. We hypothesized that the expression of cerebellar GABA(A) receptors may be affected by the mutation. Indeed, abnormal GABA(A) receptor function and expression in the cacna1a(tg) forebrain has been reported previously [Tehrani MH, Barnes EM Jr (1995) Reduced function of gamma-aminobutyric acid A receptors in tottering mouse brain: role of cAMP-dependent protein kinase. Epilepsy Res 22:13-21; Tehrani MH, Baumgartner BJ, Liu SC, Barnes EM Jr (1997) Aberrant expression of GABA(A) receptor subunits in the tottering mouse: an animal model for absence seizures. Epilepsy Res 28:213-223]. Here we show a deficit of 40.2+/-3.6% in the total number of cerebellar GABA(A) receptors expressed (gamma2+delta subtypes) in adult cacna1a(tg) relative to controls. [(3)H]Muscimol autoradiography identified that this was partly due to a significant loss of CGC-specific alpha6 subunit-containing GABA(A) receptor subtypes. A large proportion of this loss of alpha6 receptors was attributable to a significantly reduced expression of the CGC-specific benzodiazepine-insensitive Ro15-4513 (BZ-IS) binding subtype, alpha6betagamma2 subunit-containing receptors. BZ-IS binding was reduced by 36.6+/-2.6% relative to controls in cerebellar membrane homogenates and by 37.2+/-3.7% in cerebellar sections. Quantitative immunoblotting revealed that the steady-state expression level of alpha6 and gamma2 subunits was selectively reduced relative to controls by 30.2+/-8.2% and 38.8+/-13.1%, respectively, alpha1, beta3 and delta were unaffected. Immunohistochemically probed control and cacna1a(tg) cerebellar sections verified that alpha6 and gamma2 subunit expression was reduced and that this deficit was restricted to the CGC layer. Thus, we have shown that abnormal cerebellar P/Q-type VGCC activity results in a deficit of CGC-specific subtype(s) of GABA(A) receptors which may contribute to, or may be a consequence of the impaired cerebellar network signaling that occurs in cacna1a(tg) mice. 相似文献
14.
Adenosine A(2B) and A(3) receptors (ADOR) have been reported to induce coronary vasodilation in the rat. This study investigated the effect of age on ADORA(3) mediated coronary responses using hearts from rats aged 6-8 weeks (immature), 16-18 weeks (young) and 52-54 weeks (mature) perfused in Langendorff mode. APNEA (ADORA(3)>ADORA(1) agonist) was observed to activate at least two receptor subtypes to mediate a biphasic vasodilator response in hearts from immature rats. The potency of APNEA at the high affinity site was enhanced by alloxazine (ADORA(2B) antagonist) and reduced when combined with MRS1191 (ADORA(3) antagonist). This indicates that the high affinity phase is the ADORA(3), and ADORA(2B) signalling is likely to play a negative regulatory role towards the ADORA(3) mediated response. The activity at this site was also reduced with maturation. The low affinity site was inhibited by alloxazine but not MRS1191, indicating that this response is mediated by the ADORA(2B) or another receptor subtype. The response at this site did not alter with age. Cl-IB-MECA (ADORA(3) agonist) produced monophasic responses that were inhibited by alloxazine but remained unaffected by MRS1191 in all age groups. In addition the potency of Cl-IB-MECA does not change in hearts from PTX-treated rats. However, the maximal responses increased, indicating G(i) protein independent and dependent signalling. Q-PCR analysis of rat hearts indicated the presence of an ADORA(3) splice variant (ADORA(3i)), which increased in mRNA expression with age. Cl-IB-MECA responses may be mediated by this ADORA(3i). In conclusion, APNEA mediates coronary vasodilation in the rat heart via at least two receptor sites, the ADORA(3) and ADORA(2B). ADORA(3) responses are reduced while ADORA(2B) remain unchanged with maturation. In addition, the splice variant ADORA(3i) may contribute to coronary responses in the rat heart. 相似文献
15.
Digestion of Mamestra brassicae DNA with DraI produced a prominent fragment of approximately 200 bp and a ladder of electrophoretic bands with molecular weights which are a multiple of 200 bp. Southern blotting revealed that this ladder is composed of DNA fragments that are multimers of the 200-bp DraI band suggesting that DraI isolated a satellite that has been called Mamestra brassicae satellite DNA 1 (MBSAT1). MBSAT1 is the first satellite DNA isolated in Lepidoptera. In-situ
DraI digestion of chromosome spreads, together with fluorescent in-situ hybridization, showed that MBSAT1 sequences are clustered in heterochromatin of the sex chromosomes, Z and W. MBSAT1 was 234 bp long with an AT content of 60.7%. The curvature–propensity plot suggested a curvature in the MBSAT1 structure. 相似文献
16.
Leymus mollis and L. racemosus (Triticeae; Poaceae) are important as genetic resources for wheat improvement, as they carry genes for salt tolerance and disease resistance. Even though these species share common Ns and Xm genomes, the genomic relationship between these two species is not yet clearly understood. In this study, we examined the genomes of the two species by FISH and GISH, using combinations of tandem-repetitive sequences and genomic DNAs. Comparative GISH showed that genomes in the genus Leymus were diverse. Nevertheless, chromosomes of these two species were able to undergo complete meiotic pairing in hybrids, suggesting that differences in the subtelomeric heterochromatin and sequences distinguishable by GISH do not affect meiotic pairing. 相似文献
17.
M. Canonaco R. Tavolaro M. C. Cerra M. Anastasio M. F. Franzoni 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1991,87(3):634-640
Summary Quantitative autoradiography was used to investigate the distribution and effects of gonadal hormones on [3H] muscimol (specific GABAA receptor ligand) binding in the male Japanese quail brain. In gonadally intact Japanese quail brains, [3H] muscimol revealed a heterogeneous distribution with high GABAA receptor levels in the cerebellum pars granularis (656 fmol/mg wet weight of tissue) and in the pars molecularis (405 fmol/mg wet weight of tissue). Low receptor levels were found in the nucleus preopticus anterior and the nucleus lateralis of the hypothalamic regions (<220 fmol/mg wet weight of tissue) as well as thalamic nuclei such as rotundus and pretectalis (220–261 fmol/ mg wet weight of tissue). Castration resulted in [3H] muscimol binding changes in both brain areas that contain steroid receptors and brain areas devoid of steroid receptors. In fact, castration led to high binding levels in the preopticus anterior nucleus and in the anterior neostriatum area, brain areas that are known to contain gonadal steroid receptors. Castration also elevated [3H] muscimol binding in the hyperstriatum ventrale and reduced binding levels in the paleostriatum augmentatum and the stratum griseum centrale area; all of these areas are known to be devoid of gonadal steroid receptors. At this point it was also important to know whether the gonadal steroid effect is due to alterations in the number of binding sites (Bmax) and/or the affinity binding state (KD). The saturation binding study, dealing with some of the areas described above in brains of male quails castrated or castrated and treated with testosterone or estradiol, demonstrated that the steroid replacement therapy was responsible for the changes of the Bmax. Diminishing Bmax values were displayed in the hypothalamic preoptic area and the hyperstriatum ventrale of the male quail treated with testosterone and estradiol while a reduced Bmax was obtained in the anterior neostriatum of the quail treated with the former steroid. Our findings suggest that these steroids might control some centrally mediated behavior activities through effects on the maximum number of GABAA binding sites in the male Japanese quail. 相似文献
18.
T. J. Lea 《Pflügers Archiv : European journal of physiology》1986,406(3):315-322
Increases in solution pH from 6.5 to 7.0 to 7.5 at 0.1 M free Ca2+ concentration had no effect on the isometric tension of barnacle myofibrillar bundles in relaxing solutions containing 0.1–0.16 mM BAPTA. Decreases in pH in the same range were also without effect. Under the same conditions CO2-induced Ca2+ release from the SR could be readily obtained by replacing the Cl–-containing relaxing solution with one containing HCO
3
–
and 100% CO2 at the same pH. At a higher free Ca2+ of 2.5 M, there was a contraction on increasing the pH of the Cl–-containing solution from 7.0 to 7.5. This reponse could be abolished by 1 mM procaine suggesting that it was due to Ca2+ release from the SR. The protonophores monensin, gramicidin, CCCP and FCCP at concentrations of 10–100 M had no effect on resting tension at either free Ca2+ concentration and did not inhibit the response to 100% CO2. It is concluded that dissipation of a possible pH gradient across the SR membrane by protonophores does not release Ca2+ from the SR of barnacle muscle. Since both CO2 (by possibly lowering SR pH) and an increase in solution pH can release Ca2+ at 2.5 M free Ca2+, the existence of a Ca2+ release channel which is opened by a change in the trans-SR pH gradient cannot be discounted. In a separate series of experiments, the CO2-releasable Ca2+ store was first depleted by exposure of bundles to 100% CO2 in the presence of 1 mM BAPTA for 10 min and then partially reloaded by 15 s exposure to a free Ca2+ of 0.6 M buffered by 2 mM EGTA (total) in the Cl– relaxing solution. The same level of reloading was obtained when the loading solution contained HCO
3
–/100%
CO2; this result tends to discount inhibition of the Ca2+ uptake pump as a possible mechanism for CO2-induced Ca2+ release. Loading at 2.6 M free Ca2+ for 1 min resulted in almost complete recovery of the CO2 response to its value before depletion of the store. 相似文献
19.
Eun Ju Kim Min-Kyoung Kim Xing-Ji Jin Jang-Hee Oh Ji Eun Kim Jin Ho Chung 《Journal of Korean medical science》2010,25(6):980-983
We investigated the alterations of major fatty acid components in epidermis by natural aging and photoaging processes, and by acute ultraviolet (UV) irradiation in human skin. Interestingly, we found that 11,14,17-eicosatrienoic acid (ETA), which is one of the omega-3 polyunsaturated acids, was significantly increased in photoaged human epidermis in vivo and also in the acutely UV-irradiated human skin in vivo, while it was significantly decreased in intrinsically aged human epidermis. The increased ETA content in the epidermis of photoaged human skin and acute UV-irradiated human skin is associated with enhanced expression of human elongase 1 and calcium-independent phophodiesterase A2. We demonstrated that ETA inhibited matrix metalloproteinase (MMP)-1 expression after UV-irradiation, and that inhibition of ETA synthesis using EPTC and NA-TCA, which are elongase inhibitors, increased MMP-1 expression. Therefore, our results suggest that the UV increases the ETA levels, which may have a photoprotective effect in the human skin. 相似文献
20.
OBJECTIVE: In this study we investigated the effect of CGS 21680 (2-p-(2-Carboxyethyl)phenethylamino-5-N-ethylcarboxamidoadenosine hydrochloride), an adenosine A2A receptor agonist, in a model of dextran sulphate sodium (DSS)-induced colitis. METHODS: NMRI mice were fed 5 % (w/v) DSS, and were treated intraperitoneally with 0.5 mg/kg CGS 21680 or vehicle for 10 days. Changes of bodyweight, colon length, the incidence of rectal bleeding, levels of macrophage inflammatory protein (MIP)-1alpha, MIP-2, interferon gamma, interleukin (IL)-1beta, IL-12 and tumour necrosis factor-alpha from homogenates of colon biopsies, and the release of [3H]acetylcholine (ACh) from longitudinal muscle strip were determined. RESULTS: DSS significantly decreased bodyweight, colon length, and it increased the incidence of rectal bleeding and levels of MIP-1alpha, MIP-2 and IL-1beta compared to DSS-untreated animals. CGS 21680 had no effect on these changes. No change could be observed in release of ACh in DSS-induced colitis with or without CGS 21680. CONCLUSION: In summary, CGS 21680 is ineffective in ameliorating DSS-induced colitis in mice. 相似文献