Stimulation by atropine of acetylcholine release and synthesis in cortical slices from rat brain.
TL;DR: The observations made with pretreatment by botulinum type A toxin, with changes in the calcium and magnesium concentration as well as with physostigmine, all support the theory that it is primarily the release of ACh which is enhanced by atropine and that its stimulating action on the synthesis results from the increased release.
Abstract: 1. Cortical slices from rat brain were incubated in media containing the irreversible cholinesterase inhibitor soman and a high KCl concentration, and the release and synthesis of acetylcholine (ACh) were determined.2. Atropine enhanced the release and synthesis of ACh.3. Tetrodotoxin, a substance which blocks nervous conduction, did not influence the release and synthesis of ACh, in the absence or in the presence of atropine. Therefore the nerve endings are probably the site at which atropine acts when stimulating the release and synthesis of ACh.4. Pretreatment of the slices with botulinum type A toxin partially blocked the release and synthesis of ACh and reduced the extra amounts of ACh released and synthesized under the influence of atropine.5. Lowering the calcium or raising the magnesium concentration in the incubation medium reduced the release and synthesis of ACh and their enhancement by atropine.6. Physostigmine decreased the total extractable ACh content of the slices during incubation in a 25 mM KCl containing medium. This decrease was nearly prevented when the release and synthesis of ACh were inhibited by omission of the calcium ions from the medium, but was enhanced by atropine.7. The observations made with pretreatment by botulinum type A toxin, with changes in the calcium and magnesium concentration as well as with physostigmine, all support the theory that it is primarily the release of ACh which is enhanced by atropine and that its stimulating action on the synthesis results from the increased release.
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TL;DR: The feasibility of measuring acetylcholine in perfusion samples collected by means of in vivo brain dialysis in the striata of freely moving rats is demonstrated, although a considerable variation between successive samples exists.
Abstract: The present study demonstrates the feasibility of measuring acetylcholine in perfusion samples collected by means of in vivo brain dialysis in the striata of freely moving rats. The output of the dialysis device was directly connected to an automated sample valve of a HPLC-assay system that comprises a cation exchanger, a post-column enzyme reactor, and an electrochemical detector. The presence of an acetylcholinesterase inhibitor (neostigmine) in the perfusion fluid was required for the detection of acetylcholine in the perfusate. Increasing concentrations of neostigmine induced increasing amounts of acetylcholine. Continuous perfusion with a fixed concentration (2 microM) of neostigmine resulted in gradually increasing amounts of collected acetylcholine over time although a considerable variation between successive samples exists. The brain dialysis technique was further validated by studying the effect of various drugs. Systemically administered atropine increased the output of acetylcholine, whereas the addition of tetrodotoxin to the perfusion fluid resulted in a complete disappearance of the neurotransmitter.
214 citations
TL;DR: The results indicate that the nicotinic agonists nicotine and DMPP can produce a moderate enhancement of acetylcholine release by a receptor‐mediated action on cholinergic nerve terminals in the central nervous system.
Abstract: The effects of nicotine and 1,1-dimethyl-4-phenylpiperazinium (DMPP) on the release of newly synthesized [3H]acetylcholine in mouse cerebral cortical synaptosomes were examined. Nicotine and DMPP produced increases in [3H]acetylcholine release, over the level of spontaneous release, of 24% and 30%, respectively, of a maximum depolarization-induced release produced by 50 mM potassium. The maximum effect was achieved at a concentration of 1 X 10(-4) M for both agents. The time course of release indicated a slow onset of action, reaching a maximum effect at 15 min of incubation. Both nicotine and DMPP also produced a slightly greater release of total tritium, measured in the absence of cholinesterase inhibition, than of [3H]acetylcholine. The release induced by nicotine was completely antagonized by hexamethonium and was largely (58%) calcium-dependent. Nicotine also produced an increase in [3H]choline accumulation into synaptosomes. These results indicate that the nicotinic agonists nicotine and DMPP can produce a moderate enhancement of acetylcholine release by a receptor-mediated action on cholinergic nerve terminals in the central nervous system.
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References
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Book•
01 Jan 1966
TL;DR: In this article, the authors presented a case of two means regression method for the family error rate, which was used to estimate the probability of a family having a nonzero family error.
Abstract: 1 Introduction.- 1 Case of two means.- 2 Error rates.- 2.1 Probability of a nonzero family error rate.- 2.2 Expected family error rate.- 2.3 Allocation of error.- 3 Basic techniques.- 3.1 Repeated normal statistics.- 3.2 Maximum modulus (Tukey).- 3.3 Bonferroni normal statistics.- 3.4 ?2 projections (Scheffe).- 3.5 Allocation.- 3.6 Multiple modulus tests (Duncan).- 3.7 Least significant difference test (Fisher).- 4 p-mean significance levels.- 5 Families.- 2 Normal Univariate Techniques.- 1 Studentized range (Tukey).- 1.1 Method.- 1.2 Applications.- 1.3 Comparison.- 1.4 Derivation.- 1.5 Distributions and tables.- 2 F projections (Scheffe)48.- 2.1 Method.- 2.2 Applications.- 2.3 Comparison.- 2.4 Derivation.- 2.5 Distributions and tables.- 3 Bonferroni t statistics.- 3.1 Method.- 3.2 Applications.- 3.3 Comparison.- 3.4 Derivation.- 3.5 Distributions and tables.- 4 Studentized maximum modulus.- 4.1 Method.- 4.2 Applications.- 4.3 Comparison.- 4.4 Derivation.- 4.5 Distributions and tables.- 5 Many-one t statistics76.- 5.1 Method.- 5.2 Applications.- 5.3 Comparison.- 5.4 Derivation.- 5.5 Distributions and tables.- 6 Multiple range tests (Duncan).- 6.1 Method.- 6.2 Applications.- 6.3 Comparison.- 6.4 Derivation.- 6.5 Distributions and tables.- 7 Least significant difference test (Fisher).- 7.1 Method.- 7.2 Applications.- 7.3 Comparison.- 7.4 Derivation.- 7.5 Distributions and tables.- 8 Other techniques.- 8.1 Tukey's gap-straggler-variance test.- 8.2 Shortcut methods.- 8.3 Multiple F tests.- 8.4 Two-sample confidence intervals of predetermined length.- 8.5 An improved Bonferroni inequality.- 9 Power.- 10 Robustness.- 3 Regression Techniques.- 1 Regression surface confidence bands.- 1.1 Method.- 1.2 Comparison.- 1.3 Derivation.- 2 Prediction.- 2.1 Method.- 2.2 Comparison.- 2.3 Derivation.- 3 Discrimination.- 3.1 Method.- 3.2 Comparison.- 3.3 Derivation.- 4 Other techniques.- 4.1 Linear confidence bands.- 4.2 Tolerance intervals.- 4.3 Unlimited discrimination intervals.- 4 Nonparametric Techniques.- 1 Many-one sign statistics (Steel).- 1.1 Method.- 1.2 Applications.- 1.3 Comparison.- 1.4 Derivation.- 1.5 Distributions and tables.- 2 k-sample sign statistics.- 2.1 Method.- 2.2 Applications.- 2.3 Comparison.- 2.4 Derivation.- 2.5 Distributions and tables.- 3 Many-one rank statistics (Steel).- 3.1 Method.- 3.2 Applications.- 3.3 Comparison.- 3.4 Derivation.- 3.5 Distributions and tables.- 4 k-sample rank statistics.- 4.1 Method.- 4.2 Applications.- 4.3 Comparison.- 4.4 Derivation.- 4.5 Distributions and tables.- 5 Signed-rank statistics.- 6 Kruskal-Wallis rank statistics (Nemenyi).- 6.1 Method.- 6.2 Applications.- 6.3 Comparison.- 6.4 Derivation.- 6.5 Distributions and tables.- 7 Friedman rank statistics (Nemenyi).- 7.1 Method.- 7.2 Applications.- 7.3 Comparison.- 7.4 Derivation.- 7.5 Distributions and tables.- 8 Other techniques.- 8.1 Permutation tests.- 8.2 Median tests (Nemenyi).- 8.3 Kolmogorov-Smirnov statistics.- 5 Multivariate Techniques.- 1 Single population covariance scalar unknown.- 1.1 Method.- 1.2 Applications.- 1.3 Comparison.- 1.4 Derivation.- 1.5 Distributions and tables.- 2 Single population covariance matrix unknown.- 2.1 Method.- 2.2 Applications.- 2.3 Comparison.- 2.4 Derivation.- 2.5 Distributions and tables.- 3 k populations covariance matrix unknown.- 3.1 Method.- 3.2 Applications.- 3.3 Comparison.- 3.4 Derivation.- 3.5 Distributions and tables.- 4 Other techniques.- 4.1 Variances known covariances unknown.- 4.2 Variance-covariance intervals.- 4.3 Two-sample confidence intervals of predetermined length.- 6 Miscellaneous Techniques.- 1 Outlier detection.- 2 Multinomial populations.- 2.1 Single population.- 2.2 Several populations.- 2.3 Cross-product ratios.- 2.4 Logistic response curves.- 3 Equality of variances.- 4 Periodogram analysis.- 5 Alternative approaches: selection, ranking, slippage.- A Strong Law For The Expected Error Rate.- B TABLES.- I Percentage points of the studentized range.- II Percentage points of the Bonferroni t statistic.- III Percentage points of the studentized maximum modulus.- IV Percentage points of the many-one t statistics.- V Percentage points of the Duncan multiple range test.- VI Percentage points of the many-one sign statistics.- VIII Percentage points of the many-one rank statistics.- IX Percentage points of the k-sample rank statistics.- Developments in Multiple Comparisons 1966-).- 3.5 Allocation.- 3.6 Multiple modulus tests (Duncan).- 3.7 Least significant difference test (Fisher).- 4 p-mean significance levels.- 5 Families.- 2 Normal Univariate Techniques.- 1 Studentized range (Tukey).- 1.1 Method.- 1.2 Applications.- 1.3 Comparison.- 1.4 Derivation.- 1.5 Distributions and tables.- 2 F projections (Scheffe)48.- 2.1 Method.- 2.2 Applications.- 2.3 Comparison.- 2.4 Derivation.- 2.5 Distributions and tables.- 3 Bonferroni t statistics.- 3.1 Method.- 3.2 Applications.- 3.3 Comparison.- 3.4 Derivation.- 3.5 Distributions and tables.- 4 Studentized maximum modulus.- 4.1 Method.- 4.2 Applications.- 4.3 Comparison.- 4.4 Derivation.- 4.5 Distributions and tables.- 5 Many-one t statistics76.- 5.1 Method.- 5.2 Applications.- 5.3 Comparison.- 5.4 Derivation.- 5.5 Distributions and tables.- 6 Multiple range tests (Duncan).- 6.1 Method.- 6.2 Applications.- 6.3 Comparison.- 6.4 Derivation.- 6.5 Distributions and tables.- 7 Least significant difference test (Fisher).- 7.1 Method.- 7.2 Applications.- 7.3 Comparison.- 7.4 Derivation.- 7.5 Distributions and tables.- 8 Other techniques.- 8.1 Tukey's gap-straggler-variance test.- 8.2 Shortcut methods.- 8.3 Multiple F tests.- 8.4 Two-sample confidence intervals of predetermined length.- 8.5 An improved Bonferroni inequality.- 9 Power.- 10 Robustness.- 3 Regression Techniques.- 1 Regression surface confidence bands.- 1.1 Method.- 1.2 Comparison.- 1.3 Derivation.- 2 Prediction.- 2.1 Method.- 2.2 Comparison.- 2.3 Derivation.- 3 Discrimination.- 3.1 Method.- 3.2 Comparison.- 3.3 Derivation.- 4 Other techniques.- 4.1 Linear confidence bands.- 4.2 Tolerance intervals.- 4.3 Unlimited discrimination intervals.- 4 Nonparametric Techniques.- 1 Many-one sign statistics (Steel).- 1.1 Method.- 1.2 Applications.- 1.3 Comparison.- 1.4 Derivation.- 1.5 Distributions and tables.- 2 k-sample sign statistics.- 2.1 Method.- 2.2 Applications.- 2.3 Comparison.- 2.4 Derivation.- 2.5 Distributions and tables.- 3 Many-one rank statistics (Steel).- 3.1 Method.- 3.2 Applications.- 3.3 Comparison.- 3.4 Derivation.- 3.5 Distributions and tables.- 4 k-sample rank statistics.- 4.1 Method.- 4.2 Applications.- 4.3 Comparison.- 4.4 Derivation.- 4.5 Distributions and tables.- 5 Signed-rank statistics.- 6 Kruskal-Wallis rank statistics (Nemenyi).- 6.1 Method.- 6.2 Applications.- 6.3 Comparison.- 6.4 Derivation.- 6.5 Distributions and tables.- 7 Friedman rank statistics (Nemenyi).- 7.1 Method.- 7.2 Applications.- 7.3 Comparison.- 7.4 Derivation.- 7.5 Distributions and tables.- 8 Other techniques.- 8.1 Permutation tests.- 8.2 Median tests (Nemenyi).- 8.3 Kolmogorov-Smirnov statistics.- 5 Multivariate Techniques.- 1 Single population covariance scalar unknown.- 1.1 Method.- 1.2 Applications.- 1.3 Comparison.- 1.4 Derivation.- 1.5 Distributions and tables.- 2 Single population covariance matrix unknown.- 2.1 Method.- 2.2 Applications.- 2.3 Comparison.- 2.4 Derivation.- 2.5 Distributions and tables.- 3 k populations covariance matrix unknown.- 3.1 Method.- 3.2 Applications.- 3.3 Comparison.- 3.4 Derivation.- 3.5 Distributions and tables.- 4 Other techniques.- 4.1 Variances known covariances unknown.- 4.2 Variance-covariance intervals.- 4.3 Two-sample confidence intervals of predetermined length.- 6 Miscellaneous Techniques.- 1 Outlier detection.- 2 Multinomial populations.- 2.1 Single population.- 2.2 Several populations.- 2.3 Cross-product ratios.- 2.4 Logistic response curves.- 3 Equality of variances.- 4 Periodogram analysis.- 5 Alternative approaches: selection, ranking, slippage.- A Strong Law For The Expected Error Rate.- B TABLES.- I Percentage points of the studentized range.- II Percentage points of the Bonferroni t statistic.- III Percentage points of the studentized maximum modulus.- IV Percentage points of the many-one t statistics.- V Percentage points of the Duncan multiple range test.- VI Percentage points of the many-one sign statistics.- VIII Percentage points of the many-one rank statistics.- IX Percentage points of the k-sample rank statistics.- Developments in Multiple Comparisons 1966-1976.- 1 Introduction.- 2 Papers of special interest.- 2.1 Probability inequalities.- 2.2 Methods for unbalanced ANOVA.- 2.3 Conditional confidence levels.- 2.4 Empirical Bayes approach.- 2.5 Confidence bands in regression.- 3 References.- 4 Bibliography 1966-1976.- 4.1 Survey articles.- 4.2 Probability inequalities.- 4.3 Tables.- 4.4 Normal multifactor methods.- 4.5 Regression.- 4.6 Categorical data.- 4.7 Nonparametric techniques.- 4.8 Multivariate methods.- 4.9 Miscellaneous.- 4.10 Pre-1966 articles missed in [6].- 4.11 Late additions.- 5 List of journals scanned.- Addendum New Table of the Studentized Maximum Modulus.- Table IIIA Percentage points of the studentized maximum modulus.- Author Index.
4,763 citations
Journal Article•
739 citations
TL;DR: In the present investigation a study has been made by intracellular recordings in the rat diaphragm of the relation between the frequency of the miniature discharge and electrotonic polarization of the motor nerve terminals.
Abstract: Recent investigations (Boyd & Martin, 1956b; Liley, 1956b) have shown that the mammalian end-plate potential (e.p.p.) is generated by the synchronous release of quanta of transmitter whose individual spontaneous liberation gives rise to the miniature potentials. These observations immediately raise the question of the mechanism by which a co-ordinated discharge of the quanta is produced by an impulse arriving at the motor nerve terminals. Del Castillo & Katz (1954b) have investigated a similar problem at the frog myoneural junction. In the present investigation a study has been made by intracellular recordings in the rat diaphragm of the relation between the frequency of the miniature discharge and electrotonic polarization of the motor nerve terminals. A study has been made also of the effects of potassium concentration on the frequency of the miniature potentials.
372 citations
TL;DR: It has been found that excitation of the cortex, either through sensory nerves or by direct electrical stimulation, increases the ACh output and the most important step in the identification of cholinergic transmission has been the demonstration of the release of ACh during stimulation of the appropriate nerve.
Abstract: The possibility that acetylcholine (ACh) acts as a mediator of synaptic transmission in the cerebral cortex of mammals has been suggested both by experiment and by argument. It has, however, been difficult to obtain direct evidence in support of this view although many of the characteristics that might be expected of a central nervous transmitter have been clearly demonstrated for ACh in the cortex (Feldberg, 1945b, 1950, 1957; Crossland, 1960). They include the demonstration of enzymes for the synthesis and rapid destruction of ACh and the natural occurrence of this substance in the brain. ACh and drugs which are known to affect its action have been shown to influence the electrical activity of the cortex, and recently single cells in the cortex have been selectively activated by the iontophoretic application of ACh through micropipettes (Krnjevid & Phillis, 1961). However, at peripheral synapses the most important step in the identification of cholinergic transmission has been the demonstration of the release of ACh during stimulation of the appropriate nerve. Experiments of this kind, on the intact brain, offer certain difficulties and attempts by several groups of workers to demonstrate a central release of ACh during nervous stimulation have produced conflicting results (see Feldberg, 1945 b): but in 1950 Elliott, Swank & Henderson detected a release ofACh from the surface of the intact cortex and MacIntosh & Oborin (1953) showed that this release was related to the spontaneous electrical activity of the cortex. A technique similar to that of MacIntosh & Oborin has been used in the present experiments to study the effect of direct and indirect stimulation of the cortex on the local release of ACh, in an attempt to assess its significance. It has been found that excitation ofthe cortex, either through sensory nerves or by direct electrical stimulation, increases the ACh output
368 citations
TL;DR: By passing polarizing currents through the terminal portion of a motor axon and studying their effects from the other side of the synapse, it was hoped to get further information on the neuromuscular mechanism.
Abstract: The present experiments represent an attempt to throw further light on the origin of the spontaneous miniature end-plate potentials and on their relation to the transmitted response (see Fatt & Katz, 1952, 1953; Castillo & Katz, 1954c-e). In particular, it was of interest to investigate whether the rate of the spontaneous discharge is controlled by the membrane polarization of the nerve endings. By passing polarizing currents through the terminal portion of a motor axon and studying their effects from the other side of the synapse, it was hoped to get further information on the neuromuscular mechanism.
269 citations