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11.
Pituitary Adenylate Cyclase-Activating Polypeptide (PACAP) Regulation of Sympathetic Neuron Neuropeptide Y and Catecholamine Expression 总被引:4,自引:1,他引:3
Abstract: Two forms of pituitary adenylate cyclase-activating polypeptide (PACAP), the 38- and 27-amino-acid forms (PACAP38 and PACAP27, respectively), which share amino acid sequence homology with vasoactive intestinal peptide (VIP), were evaluated for their abilities to regulate sympathetic neuron catecholamine and neuropeptide Y (NPY) expression. PACAP38 and PACAP27 potently and efficaciously stimulated NPY and catecholamine secretion in primary cultured superior cervical ganglion (SCG) neurons; 100- to 1,000-fold higher concentrations of VIP were required to modulate secretion, suggesting that SCG neurons express the PACAP-selective type I receptor. PACAP38 elicited a sustained seven- to ninefold increase in the rate of NPY secretion and three-fold stimulation in the rate of catecholamine release. PACAP38 and PACAP27 produced parallel neuronal NPY and catecholamine release, but cellular levels of NPY and catecholamines were differentially regulated. Sympathetic neuron NPY content was decreased, whereas cellular total catecholamine levels were elevated by the PACAP peptides; total NPY and catecholamine levels (secreted plus cellular content) were increased. In concert with the increased total peptide and transmitter production, pro-NPY and tyrosine hydroxylase mRNA levels were elevated. Furthermore, PACAP38 was more efficacious than PACAP27 in regulating pro-NPY and tyrosine hydroxylase mRNA. SCG neuronal expression of mRNA encoding the type I PACAP receptor further supported the studies demonstrating that sympathetic neuronal levels of NPY and catecholamine content and secretion and mRNA are differentially regulated by the PACAP peptides. 相似文献
12.
Cervex brush versus vaginal–cervical–endocervical (VCE) triple smear techniques in cervical sampling
K JÄRVI 《Cytopathology》1997,8(4):282-288
Cervex brush versus vaginal–cervical–endocervical (VCE) triple smear techniques in cervical sampling
Cervex brush sampling was compared with the conventional triple vaginal–cervical–endocervical (VCE) smear technique. Nine hundred and fifty‐nine Cervex brush smears and 1064 VCE smears were studied. All smears with both methods were technically satisfactory for evaluation. Endocervical cells were found in 90.7% and metaplastic cells in 73.3% of Cervex brush samples and in 92.5% and 64.1% of VCE samples, respectively. There were significantly more metaplastic cells in smears from premenopausal women. Low grade squamous intraepithelial lesion (SIL) was found in three Cervex brush samples and in two VCE samples. High‐grade SIL was found only in one Cervex brush sample. Benign cellular changes were found in 142 Cervex brush samples and in 144 VCE samples. Sampling with the Cervex brush is efficient, simple and fast and gives high quality cervical smears for cytological evaluation. 相似文献
Cervex brush sampling was compared with the conventional triple vaginal–cervical–endocervical (VCE) smear technique. Nine hundred and fifty‐nine Cervex brush smears and 1064 VCE smears were studied. All smears with both methods were technically satisfactory for evaluation. Endocervical cells were found in 90.7% and metaplastic cells in 73.3% of Cervex brush samples and in 92.5% and 64.1% of VCE samples, respectively. There were significantly more metaplastic cells in smears from premenopausal women. Low grade squamous intraepithelial lesion (SIL) was found in three Cervex brush samples and in two VCE samples. High‐grade SIL was found only in one Cervex brush sample. Benign cellular changes were found in 142 Cervex brush samples and in 144 VCE samples. Sampling with the Cervex brush is efficient, simple and fast and gives high quality cervical smears for cytological evaluation. 相似文献
13.
大鼠颈上神经节烟碱电流的整流及失敏 总被引:1,自引:0,他引:1
在培养的新生大鼠颈上神经节交感神经元标本上,用全细胞膜片钳技术研究了烟碱型乙酰胆碱受体(nAChR)通道的整流及失敏现象。烟碱激动剂引起的全细胞电流在膜电位为负值时随膜电位呈线性改变,而在膜电位达+60mV时仍不出现外向电流,表现出强烈的内向整流。nAChR通道电流存在失敏现象,即持续恒压喷射激动剂所引起的全细胞电流随时间呈指数衰减,不能保持在峰值水平,失敏随激剂浓度呈量效关系,膜电位的超极化也加 相似文献
14.
Phenylephrine increased [3H]norepinephrine efflux and accumulation of cyclic AMP in cultured rat superior cervical ganglion cells superfused with Tyrode's solution. The purpose of this study was to determine the mechanism and relationship between these two events. Electrical stimulation (1-2 Hz), potassium chloride (50 mM), and the preferential alpha 1-adrenergic receptor agonist phenylephrine (1-100 microM) increased fractional tritium efflux, whereas methoxamine, cirazoline, and amidephrine were relatively ineffective. Phenylephrine, but not methoxamine and cirazoline, also increased cyclic AMP accumulation. Phenylephrine-induced tritium efflux was not altered by alpha- and beta-adrenergic receptor antagonists or by removal of extracellular calcium. Phenylephrine-induced cyclic AMP accumulation was blocked by the beta-adrenergic receptor antagonists propranolol and atenolol. Forskolin (10 microM) and the nonhydrolyzable cyclic AMP analogue 8-(4-chlorophenylthio)cyclic AMP (100 microM) had minimal effect on tritium efflux. However, phenylephrine-evoked increase in tritium efflux was dose dependently attenuated by the neuronal uptake blocker cocaine, and phenylephrine dose-dependently inhibited the incorporation of [3H]norepinephrine into neuronal stores. We conclude that the increase in tritium efflux induced by phenylephrine is independent of cyclic AMP accumulation and appears to be mediated by uptake of phenylephrine via the neuronal carrier-mediated amine transport process, which in turn promotes efflux of the adrenergic transmitter from its storage sites. 相似文献
15.
D. V. Sinicropi A. Dombrowski C. W. Montgomery R. K. Evans F. C. Kauffman 《Journal of neurochemistry》1980,34(5):1280-1287
Abstract: Concentrations of selected intermediates of energy metabolism whole rat superior cervical ganglia maintained in vitro by an organ culture technique were compared with values measured in small slices of this maintained under essentially the same conditions. Rates of incorporation [3 H]leucine into trichloroacetic acid-precipitable material in whole ganglia mained constant for at least 48 h: however, the oxidation-reduction state tissue as indexed by (NAD):(NADH) ratios calculated from measured amounts of lactate and pyruvate decreased more than 50% within 3 h in vitro . Ganglion explants prepared by cutting the tissue into 300 -pm transverse sections played (NAD):(NADH) ratios that were about three times greater than noted in whole ganglia maintained in vitro for the same period of time. explants contained significantly higher concentrations of pyruvate and α-ketoglutarate than whole ganglia maintained in culture. Maintenance of vorable metabolic state may support the extensive growth of neurites seen explant cultures of superior cervical ganglia. Outgrowth of processes containing catecholamines could be detected readily in explant cultures of ganglia adult rats; however, this was somewhat slower and less consistent than growth observed in explants from neonatal rats. Outgrowth of neurites adult ganglia was minimal without the addition of Nerve Growth Factor. 相似文献
16.
颈髓损伤后线粒体系列酶活性变化与线粒体功能的关系 总被引:2,自引:0,他引:2
为了探讨颈髓损伤后颈髓线粒体系列酶活性变化与线粒体功能的关系,采用Alen法造成猫颈髓损伤,观察颈髓损伤后线粒体Ca2+,Mg2+-ATP酶、Na+,K+-ATP酶、超氧化物歧化酶(SOD)活性及线粒体呼吸功能的变化。结果显示:颈髓损伤后2h至72h,Ca2+,Mg2+-ATP酶、Na+,K+-ATP酶活性、SOD活性明显降低,而线粒体呼吸控制率(RCR)、磷氧比值(P/O)、氧化磷酸化效率(OPR)也明显下降。表明颈髓损伤后Ca2+,Mg2+-ATP酶、Na+,K+-ATP酶、SOD活性与线粒体功能密切相关,提示颈髓线粒体的病理生理改变在颈髓损伤后继发性损害过程中起重要作用。 相似文献
17.
白藜芦醇作为一种广泛存在于药食同源植物中的非黄酮类多酚化合物,其抗肿瘤效果受到广泛关注,但在抑制宫颈癌方面仍缺乏体内效应的实验依据.本研究通过体内实验发现白藜芦醇具有明显的抗肿瘤生长作用,组织水平LC3B、P62和Beclin-1表达改变,推测白藜芦醇可能通过促进癌细胞的过度自噬抑制宫颈癌的进展;进一步通过体外细胞实验... 相似文献
18.
Artesunate exerts an anti‐immunosuppressive effect on cervical cancer by inhibiting PGE2 production and Foxp3 expression 下载免费PDF全文
19.
Malyukova A. V. Loginov W. I. Hodyrev D. S. Kadyrova E. L. Pronina I. V. Ivanova T. A. Kisseljov F. L. Zabarovsky E. R. Kisseljova N. P. Braga E. A. 《Molecular Biology》2004,38(6):857-864
Methylation-sensitive restriction endonuclease analysis (MSRA) followed by polymerase chain reaction (PCR) have been used to estimate the methylation level of 13 CpG dinucleotides in the promoter region of the putative suppressor gene RASSF1A (3p21.31) in squamous cell carcinomas of the uterine cervix (SCCs) carrying human papillomavirus (HPV) types 16, 18, and related types. Methylation of 3 to 13 CpG pairs has been found in 64% (25 out of 39) tumor DNA samples, 22% (2 out of 9) DNA samples from morphologically normal tissues adjacent to the tumor (P = 0.0306), and two out of three DNA samples from peripheral blood leukocytes of carcinoma patients. These CpG pairs are not methylated in the DNA of leukocytes of healthy donors (0 out of 10). The methylation level of the RASSF1A promoter region studied in tumors of the patients with regional lymph node metastases is significantly higher than in tumors of the patient that have no metastases (P = 8.5 × 10–12). The methylation frequency of gene RASSF1A is two times higher than the frequency of hemi- and homozygous deletions in the chromosome 3 region where the gene is located. The data obtained indicate that methylation is one of the main mechanisms of the RASSF1A gene inactivation in HPV-positive human cervical tumors. The methylation of this gene may be an early event in the genesis of cervical tumors, the methylation level increasing with tumor progression. 相似文献
20.
子宫颈糜烂病毒病因的探讨 总被引:17,自引:0,他引:17
491份宫颈拭子病毒分离结果表明:糜烂宫颈单纯疱疹病毒(HSV)分离阳性率(30.8%)是正常宫颈(2.6%)的11.8倍,用人干扰素治疗一个疗程后,病毒分离率下降至疗前的1/4.36例糜烂宫颈活体组织DNA分子杂交表明,乳头瘤病毒16型(HPV-16)阳性者占52.8和,HPV-18占17.9%,HPV-6B占28.1%,HPV-11占7.7%,251例宫颈糜烂患者经人(?)D型基因工程干扰素双盲对比治疗后,总有效率达93.8%,显效率达60%,分析临床疗效与HSV分离率的变化表明,临床有效病例中有35%(49/140)在治疗后病毒阴转,有57%在疗前疗后均未分离出HSV,有5%在疗前疗后保持阳性不变,有2.9%疗前阴性,疗后阳性,上述结果表明,HSV和HPV与慢性宫颈炎有一定关系。 相似文献