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91.
Modulation of electrically evoked [3H]-noradrenaline release from cultured chick sympathetic neurons
Clemens Allgaier Angelika Schobert Manuela Belledin Rolf Jackisch Georg Hertting 《Naunyn-Schmiedeberg's archives of pharmacology》1994,350(3):258-266
In the present study we attempted a comprehensive characterization of modulation of noradrenaline release from chick sympathetic neurons. To this purpose sympathetic neurons derived from chick lumbosacral paravertebral ganglia and kept in culture for 7 days were loaded with 0.05 mol/l [3H]-noradrenaline and subjected to electrical field stimulation (36 pulses/3 Hz). Since the released transmitter was partially recaptured, superfusion was usually performed in the presence of (+)-oxaprotiline, an inhibitor of noradrenaline re-uptake. [3H]-Noradrenaline was released in a manner which was dependent on extracellular Ca2+ and sensitive to tetrodotoxin (TTX). -Conotoxin (-CTX; 100 nmol/l) abolished [3H]-noradrenaline release indicating that influx through -CTX-sensitive Ca2+-channels was essential for transmitter release. 1,4-dihydro-2,6-dimethyl-5-nitro4-[2-(trifluoromethyl)-phenyl]-3-pyridine carboxylic acid methyl ester ((±)Bay K 8644) and 4-(4-benzofurazanyl)-1,4-dihydro-2,6-dimethyl-3-nitro-5-pyridinecarboxylic acid isopropyl ester ((±)-202-791), agonists at L-type voltage sensitive Ca2+-channels (VSCCs), increased noradrenaline release and induced, in addition, an overflow of tritium which was Ca2+-dependent and prevented by the presence of TTX. The L-type VSCC antagonists (–)-202-791 and (+)-4-(4-benzofurazanyl)-1,4-dihydro2,6-dimethyl-3,5-pyridinedicar boxylic acid methyl, isopropyl ester ((+)-PN 200–110) diminished [3H]-noradrenaline release. These data suggest that L-type VSCCs, probably located on the cell body of the neuron, play an additional role in modulation of release. The full 2-adrenoceptor agonists 5-bromo-6-(2-imidazolin-2-ylamino)-quinoxaline ( UK-14,304) and noradrenaline significantly inhibited noradrenaline release, whereas clonidine, a partial a2-agonist, produced only a slight inhibition even at 10 mol/l. The facilitation of noradrenaline release observed in the presence of the 2-adrenoceptor antagonist rauwolscine was very low in comparison to that obtained with brain slices and isolated smooth muscle tissues. These results corroborate the observation that noradrenaline release from chick sympathetic neurons is regulated by an 2-adrenoceptor which needs further subtype characterization. The experiments were mostly performed at 25°C, since a rise in temperature to 37°C increased the resting outflow, but not the evoked overflow of tritium, approximately 4-fold. In the presence of pargyline to block monoamine oxidase, however, the temperature-dependent enhancement was diminshed and the release showed properties comparable to those observed at 25°C (with respect to TTX-sensitivity, Ca2+ dependence and modulation via 2-adrenoceptors). In addition to the 2-adrenoceptors, we detected inhibitory -adrenoceptors, opioid and receptors, and P2 purinoceptors as well as facilitatory prostaglandin (PG) E receptors. No indication was found for a functional relevance of 5-hydroxytryptamine (5-HT), opioid , PGD, adenosine A1 or glutamate receptors. In conclusion, electrically evoked noradrenaline release from cultured chick sympathetic neurons shows the properties of action-potential-induced transmitter release and is bidirectionally regulated by various substances. Therefore, sympathetic neurons in culture offer the possibility to investigate directly the mechanisms bringing about receptor-coupled modulation of transmitter release.Abbreviations ATP
adenosine 5-triphosphate
- Bay K 8644
1,4-dihydro-2,6-dimethyl-5-nitro-4-[2-(trifluoromethyl)-phenyl]-3-pyridine carboxylic acid methyl ester
- DAGO
(d-Ala2,N-methyl-Phe4,Gly-ol5)-enkephalin
- DPDPE
(d-Pen 2,5)-enkephalin
- 5-HT
5-hydroxytryptamine
- -CTX
-conotoxin
- KRBB
modified Krebs-Ringer bicarbonate buffer
- NMDA
N-methyl-d-aspartic acid
- PG
prostaglandin
- PN 200-110
4-(4-benzofurazanyl)-1,4-dihydro-2,6-dimethyl-3,5-pyridinedicarboxy lic acid methyl, isopropyl ester
- R-PIA
R(–)-N6-(2-phenyl-isopropyl)-adenosine
- TTX
tetrodotoxin
- U-50,488H
trans-3,4-dichloro-N-methyl-N-[2-(1-pyrrolidinyl)-cyclohexyl]-benzene acetamide
- UK-14,304
5-bromo-6-(2-imidazolin-2-ylamino)-quinoxaline
- VSCC
voltage sensitive Ca2+-channel
- 202-791
4-(4-benzofurazanyl)-1,4-dihydro-2,6-dimethyl-3-nitro-5-pyridinecarboxylic acid isopropyl ester
Correspondence to: C. Allgaier at the above address 相似文献
92.
Six mainstream and twelve sidestream infrared carbon dioxide (CO2) analysers were tested for accuracy of the CO2 display value, alarm activation and the effects of nitrous oxide (N2O), oxygen (O2) and water vapour according to the ISO Draft International Standard (DIS) #9918. Mainstream analysers (M-type): Novametrix Capnogard 1265; Hewlett Packard HP M1166A (CO2module HP M1016A); Datascope Passport; Marquette Tramscope 12; Nellcor Ultra Cap N-6000; Heilige Vicom-sm SMU 611/612 ETC. Sidestream analysers: Brüel &; Kjaer Type 1304; Datex Capnomac II; Marquette MGA-AS; Datascope Multinex; Ohmeda 4700 OxiCap (all type S1: respiratory cycles not demanded); Biochem BCI 9000; Bruker BCI 9100; Dräger Capnodig and PM 8020; Criticare Poet II; Heilige Vicom-sm SMU 611/612 A-GAS (all type S2: respiratory cycles demanded). The investigations were performed with premixed test gases (2.5, 5, 10 vol%, error ?1% rel.). Humidification (37° C) of gases were generated by a Dräger Aquapor. Respiratory cycles were simulated by manually activated valves. All monitors complied with the tolerated accuracy bias in CO2 reading (≤ 12% or 4 mmHg of actual test gas value) for wet and dry test gases at all concentrations, except that the Marquette MGA-AS exceeded this accuracy limit with wet gases at 5 and 10 vol% CO2. Water condensed in the metal airway adapter of the HP M1166A at 37° C gas temperature but not at 3(P C. The Servomex 2500 (nonclinical reference monitor), Passport (M-type), Multinex (S1-type) and Poet II (S2-type) showed the least bias for dry and wet gases. Nitrous oxide and O2 had practically no effect on the Capnodig and the errors in the others were max. 3.4 mmHg, still within the tolerated bias in the DIS (same as above). The difference between the display reading at alarm activation and the set point was in all monitors (except in the Capnodig: bias 1.75 mmHg at 5 vol% CO2) below the tolerated limit of the DIS (difference ≤ 0.2 vol%). The authors conclude that the tested monitors are safe for clinical use (except those failing the DIS limits). The accuracy of the CO2-reading (average of mean absolute bias) is better in the M-type than in the S1- or S2- type analysers although no statistical (nor clinical) significant differences could be detected. Most manufacturers work with stricter limits than those proposed by the DIS. 相似文献
93.
Stefan Birkenhake Susanne Leykamm Peter Martus Rolf Sauer 《Strahlentherapie und Onkologie》1999,175(3):97-101
Purpose
To evaluate acute toxicity and efficacy of simultaneous radiochemotherapy for invasive urothelial cancer of the bladder.Patients and Methods
From September 1993 to July 1997,61 patients with invasive bladder cancer were treated with a transurethral resection (TURB) followed by radiochemotherapy (RCT). Twenty-five received a combination of 5-FU and cisplatin. The prescribed doses were 600 mg/m2 5-FU daily as continuous infusion over 5 days each in the 1st and 5th treatment week and 20 mg/m2 cisplatin daily at the same days as a short infusion. The pelvis was irradiated with 54 Gy, the bladder with 59.4 Gy and the paraortic nodes in 7 cases with 45 Gy, respectively. Six to 8 weeks after RCT a second TURB was performed for reasons of restaging.Results
Twenty out of 25 patients received at least 80% of the prescribed chemotherapy, in 13 cases the full dose could be given. Gastrointestinal toxicity of Grade I and II occurred in 10 cases, 1 patient developed severe diarrhea (Grade VI). After the 1st course of chemotherapy 7 patients had leucoor thrombopenia of Grade III. One patient had a leucopenia of Grade IV. After the 2nd course 4 patients developed Grade III leuko- and thrombopenia, 1 of Grade IV. Two Grade II anemia were found. All more severe toxicities and necessary dose reductions were related to radiation of the paraaortic nodes. No life threatening infections, bleedings or cardiotoxicity was found. Restaging TURBs resulted in 22 complete remissions, 1 patient had a de-novo-carcinoma (Tis) at this time, 2 were non-responders (8%). After a median follow-up of 38 months 20 patients are alive (80%).Conclusions
1. If irradiation of paraaortic nodes is necessary, 5-FU should not be applied, because the gastrointestinal toxicity is too extensive. In all other cases side effects are tolerable and can be managed by supportive care. 2. The first results are promising and should be evaluated in a prospective study. 相似文献94.
Tor Elsås Rolf Uddman Frank Sundler 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》1996,234(9):573-580
Purpose: To study the occurrence and distribution of the neuropeptide pituitary adenylate cyclase-activating peptide (PACAP) in ocular and orbital structures of the cat. Methods: Immunocytochemistry to localize PACAP and double immunostaining to detect co-localization of PACAP with other neuropeptides. Results: Numerous PACAP-immunoreactive nerve fibers were observed in the lacrimal gland, choroid and retroocular arteries. There was a sparse supply of PACAP-containing nerve fibers in the iris, ciliary body and conjunctiva. Subpopulations of PACAP-containing nerve fibers stored vasoactive intestinal peptide (VIP) or calcitonin gene-related peptide (CGRP). Around 10% of the ganglion cells in the sphenopalatine ganglion harbored PACAP immunoreactivity. In the trigeminal ganglion around 5% of the neuronal cell bodies and in the ciliary ganglion only occasional ganglion cells contained PACAP immunoreactivity. PACAP immunoreactivity co-localized with VIP in the sphenopalatine ganglion and with CGRP in the trigeminal ganglion. Conclusion: PACAP-containing nerves in the eye and associated structures demonstrate a distribution pattern resembling that of VIP. Subpopulations of nerve fibers containing PACAP immunoreactivity store VIP or CGRP immunoreactivity. Neuronal PACAP in the eye and orbit may take part in regulation of smooth muscle tone, glandular secretion and sensory processing. 相似文献
95.
Udo Kaisers Dirk Pappert Jan M. Langrehr Horst Undi Peter Neuhaus Rolf Rossaint 《Transplant international》1996,9(3):214-220
The purpose of this study was to determine the effects of vasoactive treatment with dopamine (DO), dopexamine (DX), and dobutamine (DOB) on hemodynamics, oxygen transport and hepatic venous oxygen saturation (SvhO2) after orthotopic liver transplantation (OLT). A pulmonary artery catheter was inserted into the right hepatic vein of 17 OLT patients. Timed infusion of DO, DX, and DOB was performed at the following rates: DO at 4 and 8 g/kg per minute, and DOB at 5 and 10 g/kg per minute. Hemodynamics, oxygen transport variables, and SvhO2 were assessed. Each catecholamine induced a significant increase in cardiac index, oxygen delivery, and SvhO2. Mean arterial pressure was increased during DO and DOB, but significantly reduced during DX. Each inotrope increased oxygen delivery in parallel with SvhO2, suggesting a corresponding increase in hepatic oxygen supply. Therefore, it appears that each vasoactive drug may be utilized in OLT patients to provide oxgen delivery without impairment of splanchnic oxygenation. 相似文献
96.
Rolf R. Engel 《European archives of psychiatry and clinical neuroscience》1980,229(2):165-177
Zusammenfassung Das MMPI-Interpretationssystem von Lachar (1974), das gegenüber den bisher verfügbaren Systemen eine Reihe von Vorteilen aufweist, wurde in einer deutschen Version an 1190 stationären psychiatrischen Patienten auf seine Gültigkeit hin untersucht. Von den 153 Texten der Interpretationsbibliothek wurden diejenigen 114 Texte, die voneinander unabhängige Merkmale eines MMPI-Profils interpretieren, bei jedem Vorkommen im Einzelfall von dem behandelnden Psychiater hinsichtlich der interpretativen Treffsicherheit beurteilt. Im Durchschnitt wurden von jeweils 100 Texten 83 als zutreffend bezeichnet. Bei der Analyse der einzelnen Programmteile zeigte sich, daß die Treffsicherheit bei psychopathologisch auffälligen MMPI-Profilen wesentlich höher war als bei Profilen im Normbereich. Die in dieser Untersuchung gefundenen Trefferraten korrelierten hoch mit denen der amerikanischen Originaluntersuchung, was die spezifische und replizierbare Gültigkeit der einzelnen Texte bestätigt. Das vorliegende Interpretationssystem bietet damit auf der Grundlage des MMPI eine Persönlichkeitsbeschreibung, für die in verschiedenen psychiatrischen Einsatzbereichen und verschiedenen Sprachen eine gute interpretative Treffsicherheit im Einzelfall nachgewiesen ist.Eine frühere Fassung dieser Arbeit wurde auf dem 31. Kongreß der Deutschen Gesellschaft für Psychologie in Mannheim vorgetragen. Ich danke Frau Dipl. Psych. Kornelia Zangl und Frau Dr. Pola Engel-Sittenfeld für ihre Hilfe bei der Übersetzung der Interpretationstexte. Langjährige wertvolle Mitarbeit haben Frau Irmtraud Reinhold bei der Testdurchführung, Frau Gabi Kunze bei der Programmierung des Interpretationssystems und bei der Verarbeitung der Daten geleistet 相似文献
97.
C J Coté N Rolf L M Liu N G Goudsouzian J F Ryan A Zaslavsky R Gore T D Todres S Vassallo D Polaner 《Anesthesiology》1991,74(6):980-987
This single-blind study examined four levels of monitoring in 402 pediatric cases. Patients were randomly assigned to one of four groups: 1) oximeter and capnograph; 2) only oximeter; 3) only capnograph; or 4) neither oximeter nor capnograph data available to the anesthesia team. An anesthesiologist, not involved in patient care, observed all cases and continuously recorded hemoglobin oxygen saturation (Spo2), ECG, expired CO2, and the oximeter plethysmographic output. Mean age, weight, ASA physical status, airway management (mask or endotracheal tube), and anesthetic technique were similar in each group. Two-hundred sixty problems were documented in 153 patients. Fifty-nine events in 43 patients resulted in "major" desaturation (Spo2 less than or equal to 85% for greater than or equal to 30 s). Fifteen "major" capnograph events (esophageal intubation, disconnection, accidental extubation, or obstructed endotracheal tube) were observed in 11 patients; 8 of these also developed varying degrees of desaturation. One-hundred thirty "minor" desaturation events (Spo2 less than or equal to 95% for greater than 60 s) and 79 "minor" desaturation events (hypercarbaria or hypocarbia) were observed. A number of problems fulfilled criteria in multiple categories. Infants less than or equal to 6 months of age had the highest incidence of major desaturation events (18 of 65 [27%]) compared to toddlers 7-24 months of age or children greater than 24 months of age (P less than 0.001). Blinding the oximeter data increased the number of patients (12 vs. 31) experiencing major desaturation events (P = 0.003); blinding the capnograph data altered neither the frequency of desaturation events nor the incidence of major capnograph events.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
98.
99.
Keitaro Hashimoto Otto Hauswirth Heinz D. Wehner Rolf Ziskoven 《Naunyn-Schmiedeberg's archives of pharmacology》1979,307(1):9-19
Summary The pacemaker current — i
K2 — in cardiac Purkinje fibres was analysed using the voltage clamp technique described by Deck et al. (1964). (–)-Adrenaline (5.5 · 10–6 M) causes the wellknown shift of the Hodkin-Huxley kinetics in the depolarizing direction. Procaine (7.3·10–4 M) does not cause any further shift of s
in the presence of adrenaline. Atenolol (3.8·10–5 M) causes a backshift of the kinetics in the negative direction in the presence of adrenaline and procaine. The instantaneous current-voltage relationship (
) is altered neither with adrenaline, nor with procaine or atenolol. The results exclude the possibility that the local anaesthetic side effect of many beta-adrenoceptor blocking agents may be involved in the backshift of the s-kinetics. The voltage dependence of the reciprocals of the time constants is shifted in a similar way as s
by the sympathomimetic or blocking drugs. Following the application of (–)-adrenaline (5.5·10–6 M) the (–)-isomere of penbutolol (1.7 and 3.5·10–6 M) is about equally effective in shifting the kinetics back as the (+)-isomere (3.5·10–5 M). In the presence of (–)-adrenaline, the (+)- and (–)-forms of penubutolol cause virtually no change of the instantaneous current-voltage relationship,
. Thus, (–)-adrenaline and (+)- and (–)-penbutolol are aiming for the s-kinetics whose voltage dependence is controlled by the electric field near the i
K2-channel of the membrane and do not influence the number of the i
K2-channels. These findings suggest that the sympathomimetic or blocking agents influence the s-kinetics of the pacemaker current i
K2 by altering the electric field; the fully activated current-voltage relationship which is proportional to the number of the open i
K2-channels is not subject to any appreciable modification. The results conclusively show that the kinetics of the pacemaker current can be controlled by beta-adrenoceptors. 相似文献
100.
First experience with gamma probe guided sentinel lymph node surgery in penile cancer 总被引:3,自引:0,他引:3
Wawroschek F Vogt H Bachter D Weckermann D Hamm M Harzmann R 《Urological research》2000,28(4):246-249
Because of the curative approach, the detection of lymph node metastases in squamous cell carcinoma (SCC) of the penis is
of significant clinical relevance. Sentinel lymph node (SLN) identification by means of lymphangiography has been proven to
be insufficiently safe. However, the high morbidity of inguinal lymphadenectomy and the considerable individual variability
regarding the location of lymph node metastases justify the necessity of a technique that enables the identification of SLNs.
Since 1998, SLNs have been intraoperatively identified and selectively dissected, after peritumoral injection of technetium-99m
nanocolloid and using lymphoscintigraphy, in three patients (one with malignant melanoma and two with SCC). At least one SLN
could be detected in each patient. The maximum surgical time was 30 min. There were no severe complications. Lymph node metastases
did not occur in any patient. Upon a mean follow-up of 10 months, all patients are currently free of tumor. Owing to the long-term
results of sentinel lymphadenectomy in malignant melanoma of other locations and our preliminary results with respect to penile
carcinoma, we consider the current method appropriate as the only primary operation for lymph node staging in early stages
and, in combination with modified inguinal lymphadenectomy, in locally advanced stages.
Received: 24 November 1999 / Accepted: 21 April 2000 相似文献