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71.
The role of platelet activating factor (PAF) in physiology and pathology of the central nervous system 总被引:4,自引:0,他引:4
Farbiszewski R Dudek H Skrzydlewska E Lewko J 《Neurologia i neurochirurgia polska》2002,36(4):801-808
This review describes the role of platelet activating factor (PAF) in the central nervous system injury. Cerebral ischaemia, traumatic injury of central nervous system, metabolic, toxic and degenerative neuropathy, and also the increase in Ca2+ concentration in the cell, are strong stimulators of PAF synthesis and its release from cell membranes. Neurons, glial and microglial cells, monocyte cell populations, macrophages and endothelial cells of blood vessels are the targets of platelet activating factor. The release of PAF leads to ischaemia of nervous tissue, acute traumatic or nontraumatic injuries, degenerative and metabolic nervous system disorders in adults. The use of PAF receptor antagonists prevents partially cell injury in central nervous system and leukocyte adhesion to endothelial cells. 相似文献
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73.
Samochowiec J Kucharska-Mazur J Kaminski R Smolka M Rommelschpacher H Wernicke C Tymicz A Schmidt LG 《Psychiatry research》2002,111(2-3):229-233
Abnormalities in monoamine neurotransmission have been implicated in the pathogenesis of alcoholism, mood disorders and schizophrenia. Murine norepinephrine transporter gene (NET) has been mapped to a region on chromosome 8 where a quantitative trait locus for ethanol sensitivity. Therefore we tested whether norepinephrine transporter (NET) gene variants confer susceptibility to either alcohol dependence or severe alcohol withdrawal symptoms. There is a highly polymorphic silent G1287A mutation in the NET gene. In our study 157 alcoholics and 185 healthy unrelated matched control subjects were analyzed for a silent G1287A mutation. No significant differences in allele and genotype distribution between control subjects f(A)=0.33 and alcoholics f(A)=0.29 were found. No significant results were found in more homogenous subgroups, i.e. alcoholics with severe alcohol withdrawal (seizures, delirium), early onset age<26 nor dependent patients with positive familial history of alcoholism. These results suggest that the NET gene polymorphism in exon 9 accession number: mRNA: NM_001043, genomic contig.: NT_019610, is unlikely to be involved in the susceptibility to alcoholism and severe alcohol withdrawal. 相似文献
74.
75.
Environmental enrichment has been repeatedly shown to affect multiple aspects of brain function, and is known to improve cognitive, behavioral, and histopathological outcome after brain injuries. The purpose of the present experiments was to determine the effect of an enriched environment on behavioral aberrations observed in male rats exposed to valproic acid on day 12.5 of gestation (VPA rats), and proposed on the basis of etiological, anatomical, and behavioral data as an animal model of autism. Environmental enrichment reversed almost all behavioral alterations observed in the model. VPA rats after environmental enrichment (VPA-E) compared to VPA rats reared in standard conditions have higher sensitivity to pain and lower sensitivity to nonpainful stimuli; stronger acoustic prepulse inhibition; lower locomotor, repetitive/stereotypic-like activity, and enhanced exploratory activity; decreased anxiety; increased number of social behaviors; and shorter latency to social explorations. In comparison with control animals (Con), VPA-E rats exhibited increased number of pinnings in adolescence and social explorations in adulthood, and were less anxious in the elevated plus maze. Similar differences in social behavior and anxiety were observed between control rats exposed to environmental enrichment (Con-E) and control group reared in standard conditions. These results suggest that postnatal environmental manipulations can counteract the behavioral alterations in VPA rats. We propose environmental enrichment as an important tool for the treatment of autism spectrum disorders. 相似文献
76.
Jadwiga Robak Aldona Dembińska-Kieć Ryszard Gryglewski 《Biochemical pharmacology》1975,24(22):2057-2060
Saturated fatty acids (C10, C12, C14, C16 and C18) as well as lauryl sulphate inhibit the microsomal prostaglandin synthetase of bovine seminal vesicles (BSVM). The most potent inhibitors are lauryl sulphate, lauric and myristic acids (). The last two acids are strong ligands to hydrophobic sites of albumin. Indomethacin is also strongly bound to the hydrophobic sites of albumin; however, indomethacin inhibits the generation of prostaglandins at a concentration approximately 2500 times lower than the most active fatty acid inhibitor. The inhibitory action of fatty acids and indomethacin on prostaglandin synthetase activity has been measured by estimation of either PGE2 or malondialdehyde, which are generated from arachidonic acid by BSVM. The former procedure is more reliable and reproducible than the latter. 相似文献
77.
Opioids in neuropathic pain 总被引:1,自引:0,他引:1
Opiates lack potent analgesic efficacy in neuropathic pain although it is now generally accepted that the poor effect of these drugs reflects a reduction in their potency. Reduction of morphine antinociceptive potency was postulated to be due to the fact that nerve injury altered the activity of opioid systems or opioid specific signaling. Endogenous opioid systems were found to be represented in the regions involved in the nociception and are implicated in chronic pain. Opioid peptides biosynthesis and opioid receptors density in the nociceptive pathways and their functions change under various conditions associated with neuropathic pain following damage to the spinal cord and injury of peripheral nerves. Identification of a role of opioid systems in neuropathic pain and molecular and cellular mechanisms underlying these processes are of importance to understanding of the opioid action in neuropathic pain that will hopefully facilitate development of therapeutic strategies in which effectiveness of opioids in alleviation neuropathic pain is increased. 相似文献
78.
79.
Nitrite infusions to prevent delayed cerebral vasospasm in a primate model of subarachnoid hemorrhage 总被引:16,自引:0,他引:16
Context Delayed cerebral vasospasm causes permanent neurological deficits or death in at least 15% of patients following otherwise successful treatment for ruptured intracranial aneurysm. Decreased bioavailability of nitric oxide has been associated with the development of cerebral vasospasm. Objective To determine whether infusions of nitrite will prevent delayed cerebral vasospasm. Design, Setting, and Subjects A total of 14 anesthetized cynomolgus monkeys had an autologous blood clot placed around the right middle cerebral artery. Cerebral arteriography was performed before clot placement and on days 7 and 14 to assess vasospasm. The study was conducted from August 2003 to February 2004. Interventions A 90-mg sodium nitrite intravenous solution infused over 24 hours plus a 45-mg sodium nitrite bolus daily (n = 3); a 180-mg sodium nitrite intravenous solution infused over 24 hours (n = 3); or a control saline solution infusion (n = 8). Each was infused continuously for 14 days. Main Outcome Measures Nitrite, S-nitrosothiol, and methemoglobin levels in blood and cerebrospinal fluid and degree of arteriographic vasospasm. Results In control monkeys, mean (SD) cerebrospinal fluid nitrite levels decreased from 3.1 (1.5) µmol/L to 0.4 (0.1) µmol/L at day 7 and to 0.4 (0.4) µmol/L at day 14 (P = .03). All 8 control monkeys developed significant vasospasm of the right middle cerebral artery, which was complicated by stroke and death in 1 animal. Sodium nitrite infusions increased the nitrite and methemoglobin levels (<2.1% of total hemoglobin) in the blood and cerebrospinal fluid without evoking systemic hypotension. Nitrite infusion prevented development of vasospasm (no animals developed significant vasospasm; mean [SD] reduction in right middle cerebral artery area on day 7 after subarachnoid hemorrhage of 8% [9%] in nitrite-treated monkeys vs 47% [5%] in saline-treated controls; P<.001). There was a negative correlation between the concentration of nitrite in cerebrospinal fluid and the degree of cerebral vasospasm (P<.001). Pharmacological effects of nitrite infusion were also associated with the formation of S-nitrosothiol in cerebrospinal fluid. There was no clinical or pathological evidence of nitrite toxicity. Conclusion Subacute sodium nitrite infusions prevented delayed cerebral vasospasm in a primate model of subarachnoid hemorrhage. 相似文献
80.
Bień S Kamiński B Zyłka S Mezyk R Piasta Z Markowski J Paluch J Kordylewska M Wierzbicka M Morshed K Gryczyński M Murlewska A Modrzejewski M Składzień J Jaworowska E Matyja G Burduk P Müller M Kowalska B Mikaszewski B Misiołek M Namysłowski G Bruzgielewicz A Osuch-Wójcikiewicz E Szymański L Krecicki T Karasiewicz P Mikulewicz W Pietrysiak A Jurkiewicz D Kubik P Janeczek T 《Otolaryngologia polska. The Polish otolaryngology》2005,59(2):169-181
On the base of retrospective analysis of 12,888 cases of carcinoma of larynx and hypopharynx, diagnosed in 19 ENT Departments in Poland from 1991 to 2001, the assessment of basic epidemiological data, including the localization of tumor and stage of local and clinical advancement of the disease at the time of diagnosis has been conducted. In analyzed period of 11 years the trends to change of the mentioned above parameters has been examined. The significant increase of female patients in this period was observed, with average proportion M:F = 8:1. The glottis localization of carcinoma dominated (47.6%), followed by supraglottis (40.8%) and pyriform fossa (7.8%), with significant increase of pyriform fossa tumors in the analyzed period of 11 years. In the majority of cases the carcinoma of larynx and hypopharynx was diagnosed in the advanced stage (T3 + T4) of local disease, with the highest percentage in localization within the pyriform fossa (81.0%), and the lowest percentage in glottis tumors (45.6%). The regional lymph nodes metastases has been diagnosed in 46.7% of the analyzed group, with the highest percentage in tumors localized in pyriform fossa (82.9%), and the lowest percentage in tumors of glottis localization (33.1%). In the 11 years time the significant drop down of N0 cases and tendency to increase of N2 and N3 in the supraglottis localization of tumor. The distant metastases in the analyzed group at the time of diagnosis has been registered in 2.0%, with the highest percentage in posterior pharyngeal wall (7.6%) and pyriform fossa (7.4%). The authors postulate the renewal of prospective study on epidemiology, clinical characteristics and treatment results of larynx and hypopharynx carcinoma in Poland. 相似文献