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91.
A. N. Aleksandrov V. I. Ovsyannikov 《Bulletin of experimental biology and medicine》1993,116(4):1186-1188
Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 116, N
o
10, pp. 341–343. October, 1993 相似文献
92.
I. R. Tupeev G. N. Kryzhanovskii E. V. Nikushkin M. M. Bordyukov S. M. Yuzefova 《Bulletin of experimental biology and medicine》1993,116(4):1213-1215
Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 116, N
o
10, pp. 362–364, October, 1993 相似文献
93.
Fabrizio Tagliavini Giorgio Giaccone Orso Bugiani Blas Frangione 《Acta neuropathologica》1993,85(3):267-271
Summary Here ditary cerebral hemorrhage with amyloidosis Dutch type (HCHWA-D) is characterized clinically by recurrent strokes and pathologically by deposition of amyloid (A) in cerebral vessel walls and, to a lesser extent, in the neuropil. Distinct from Alzheimer's disease, amyloid formation in HCHWA-D is not associated with neurofibrillary changes. Since a central issue in the pathophysiology of Alzheimer's disease and related conditions is the role of A in the neurodegencrative process, we investigated HCHWA-D brains for the presence of neuritic abnormalities using antibodies to ubiquitin and to phosphorylated neurofilaments. The study showed that amyloid deposits in the vessel walls and in the neuropil were surrounded by abnormal ubiquitinated neurites, suggesting that A deposition induces neuritic changes.Supported by the Italian Ministry of Health. Department of Social Services, and by N.I.H. Grants AG05891 and AG08721 (to B.F.) 相似文献
94.
Summary The effects on the substantia nigra of -dihydroergocryptine (DEK), a drug with strong dopaminomimetic activity, were tested with a severe 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) treatment in monkeys. Compared with monkeys treated with MPTP alone, the animals which received DEK plus MPTP showed reduced neuronal death in the substantia nigra. The reactive astrocytes were increased in number. Moreover, several axons which were immunopositive to phosphorylated neurofilament proteins and with features similar to those of control animals were seen in the pars compacta. The findings suggest that DEK preserves neuronal morphology and brain architecture.supported by Italian M.U.R.S.T. grants (to G.B.) and by Poli S. P. A., Rozzano, Milano 相似文献
95.
J. C. Reubi P. C. Emson T. M. Jessell L. L. Iversen 《Naunyn-Schmiedeberg's archives of pharmacology》1978,304(3):271-275
Summary The effects of GABA, substance P and dopamine on the release of newly synthesized 3H-5-HT were investigated, using slices of rat substantia nigra superfused with l-3H-tryptophan in vitro. GABA (50 M) had no inhibitory effect on the potassium-evoked-release of 3H-5-HT. Substance P (50 M) and eledoisin (50 M) stimulated the spontaneous release of 3H-5-HT. This effect seems to be indirect and is possibly mediated by dopaminergic neurones, since the dopamine antagonist drug -flupenthixol (1 M) abolished the substance P-evoked release of 5-HT. Furthermore, it was found that substance P (10 M) stimulated 3H-dopamine release from nigral slices in vitro and the dopaminergic agonist apomorphine (50 M) also stimulated 3H-5-HT release. Substance P may, therefore, activate nigral dopaminergic neurones which then release dopamine from their dendrites. The release of dopamine may in turn stimulate 5-HT release from terminals of the raphe-nigral pathway. 相似文献
96.
Treatment with d-amphetamine produced a dose-dependent increase in startle amplitude in response to a buzzer. This increase appeared to be a reflection of a sensitization effect, i.e., enhanced responsivity as a function of repeated stimulus presentations. Treatment with -methyl-p-tyrosine, which reduced whole brain concentrations of dopamine (DA) and norepinephrine (NE), or treatment with FLA-63, which reduced only NE, antagonized the effects of d-amphetamine on the startle reflex, suggesting a role of NE in this behavior. Startle amplitude was also reduced following chronic d-amphetamine treatment. The effect of d-amphetamine on startle was found to be independent of changes in drug-induced locomotor excitation. The data of the present investigation, together with earlier reports, suggests that tolerance occurs to those behaviors that involve a noradrenergic component. 相似文献
97.
J. J. Martin J. G. Leroy C. Ceuterick J. Libert P. Dodinval L. Martin 《Acta neuropathologica》1981,53(2):87-91
Summary Two new cases of Krabbe disease were diagnosed prenatally in a family with two previous affected children. The activity of galactosylceramide--galactosidase was virtually absent in cultured amniotic cells.The prenatal diagnosis was confirmed enzymatically in cultured fibroblasts, brain, and visceral organs.Light and electron microscopy studies in both fetuses, 20 and 23 weeks of gestational age respectively, revealed the presence of typical globoid cells in the white matter of the spinal cord. Specific inclusions were also found in the brain stem and in peripheral nerves of the second fetus.A comparison with other Krabbe disease fetuses described in the literature contributes to the consensus that abnormal morphological findings can be expected in particular in the most actively myelinating areas of the nervous system.Although most of the cells containing the specific melusions are probably non-glial in nature, some of them could represent myelination glia.This work was supported by the FGWO (grants nos. 3.0033.77 and 3.0012.77), by the FRSM (grant no. 3.4542.79), and by the Baron Charles Bracht Foundation 相似文献
98.
G. Francesconi C. Grassi O. Fenili C. Chiocchetti 《European journal of plastic surgery》1981,6(2):135-140
Summary The authors, based on their own experience in this field suggest their own therapeutical view which can be described as follows: a much more frequent use of plastic procedures using sliding flaps from the cheek, associated usually with chondromucosal free grafts from the septum, will give not only much better aesthetic results but also a better guarantee against neoplastic recurrence due to the possibility of being able to carry out a much larger ablation. 相似文献
99.
K. Racké M. Sommer F. Burns B. Hering 《Naunyn-Schmiedeberg's archives of pharmacology》1991,343(4):337-343
Summary Isolated rat pineal glands were incubated in vitro and the release of endogenous noradrenaline or 5-hydroxytryptamine (5-HT) and 5-hydroxyindoleacetic acid (5-HIAA) was determined by HPLC with electrochemical detection. In the absence of test drugs, the spontaneous outflow of noradrenaline was about 10 fmol/10 min and electrical stimulation (5 Hz, 1500 pulses) evoked the release of about 70 fmol noradrenaline. Nomifensine enhanced the spontaneous outflow of noradrenaline about threefold and the electrically evoked release of noradrenaline about sixfold. In the presence of nomifensine, the 2-adrenoceptor antagonist yohimbine markedly increased the electrically evoked release of noradrenaline, whereas the 1-adrenoceptor antagonist prazosin had no effect. Clonidine inhibited the electrically evoked release of noradrenaline by about 65%, and this was antagonized by yohimbine in a competitive manner. In the absence of drugs, the initial spontaneous outflow of 5-HT was (compared with noradrenaline) very high 64 mol/10 min. It declined by 80% within 1 h of incubation in vitro. The outflow of 5-HIAA amounted initially to 38 mol/10 min and declined by 40% within 1 h of incubation. Addition of l-tryptophan (10 mol/1) after 1 h of incubation in vitro largely enhanced the outflow of 5-HT and 5-HIAA within 30 min of incubation (about ten- and fourfold, respectively). When l-tryptophan was present from the onset of incubation the initial outflow of 5-HT and 5-HIAA was only slightly elevated, but the decline was largely attenuated. Neither omission of calcium nor addition of nomifensine, clonidine or yohimbine significantly affected the spontaneous outflow of 5-HT or 5-HIAA. Likewise, neither electrical stimulation in the absence or presence of nomifensine and yohimbine nor stimulation by high potassium (45 mmol/1) significantly affected the outflow of 5-HT or 5-HIAA.In conclusion, the release of endogenous noradrenaline from the sympathetic nerves terminating in the pin eal gland is inhibited by presynaptic 2-adrenoceptors. The outflow of 5-HT from the pineal gland originates almost exclusively from non-neuronal cells, most probably the pinealocytes, and depends largely on a continuous de novo synthesis. Catabolism of 5-HT to 5-HIAA in the pineal gland occurs mainly in an extraneuronal compartment, probably the pinealocytes and/or the interstitial cells of the pineal gland.
Send offprint requests to K. Racké at the above address 相似文献
100.
L. C. Rump K. Wilde C. Bohmann P. Schollmeyer 《Naunyn-Schmiedeberg's archives of pharmacology》1992,345(3):300-308
Summary The effects of the classical dopamine DA2-receptor agonist quinpirole (LY 171555) and the recently characterized DA2-receptor agonist, carmoxirole (EMD 45609), on neurotransmission in rat isolated kidney were investigated. After preincubation with 3H-noradrenaline, the renal nerves were electrically stimulated. The stimulation induced (S-I) outflow of radioactivity was taken as an index of noradrenaline release. Quinpirole (0.3 mol/l) inhibited S-I outflow of radioactivity and pressor responses to renal nerve stimulation (RNS) at 1 Hz. Both effects of quinpirole were blocked by the DA2-receptor antagonist S(–)-sulpiride (10 mol/l). The 1, 2-adrenoceptor antagonist phentolamine (1 mol/l) did not block the inhibitory effect of quinpirole. Carmoxirole (0.003 and 0.03 mol/l) did not alter and carmoxirole (0.3 mol/l) even enhanced S-I outflow of radioactivity, however, pressor responses to RNS were markedly reduced by carmoxirole (0.003–0.3 mol/l). Pressor responses to RNS were also markedly reduced by the 1-adrenoceptor antagonist prazosin (0.1 mol/l). Carmoxirole (0.3 mol/l), prazosin (0.1 mol/l) and phentolamine (1 mol/l) totally abolished pressor responses to exogenous noradrenaline (0.05 mol/l). In contrast, quinpirole (0.3 mol/l) did not alter pressor responses to exogenous noradrenaline (0.05 mol/l). Furthermore, carmoxirole (0.003–0.3 mol/l) markedly reduced pressor responses induced by the 1-adrenoceptor agonist methoxamine (1 mol/l) but even the highest concentration of carmoxirole (0.3 mol/l) had no effect on pressor responses induced by bolus injections of either neuropeptide Y (1.5 ng) or angiotensin II (1 ng). Phentolamine (1 mol/l) by itself markedly enhanced S-1 outflow of radioactivity and pressor responses to RNS were virtually unchanged. In the presence of phentolamine carmoxirole (0.03 and 0.3 mol/l) and quinpirole inhibited S-I outflow of radioactivity and pressor responses to RNS. Phentolamine resistant pressor responses to RNS were also inhibited by the P2X-receptor desensitizing agent , -methylene adenosine triphosphate (mATP, 1 mol/l), which by itself in the presence of phentolamine did not alter S-I outflow of radioactivity. The inhibitory effects of carmoxirole (0.3 mol/l) in the presence of phentolame (1mol/l) were antagonized by S(–)-sulpiride (10 mol/l). The data suggest that activation of prejunctional DA2-receptors by quinpirole inhibits noradrenaline release and thereby reduces pressor response to RNS at 1 Hz in rat isolated kidney. Carmoxirole activates prejunctional inhibitory DA2-receptors, but this effect is masked by simultaneous blockade of inhibitory prejunctional -adrenoceptors. Pressor responses to RNS at 1 Hz in rat isolated kidney are largely due to neuronally released noradrenaline whereas phentolamine resistant pressor responses to RNS at 1 Hz are most likely due to ATP, which is co-released with noradrenaline. Carmoxirole inhibits pressor responses to RNS at 1 Hz as well as pressor responses induced by either exogenous noradrenaline or methoxamine by blocking postjunctional 1-adrenoceptors. In addition carmoxirole and quinpirole seem to block phentolamine resistant pressor responses by inhibiting ATP release through activation of prejunctional DA2-receptors.
Send offprint requests to L. C. Rump at the above address 相似文献