Mammalian Brain Extracts Research Articles

Analysis of Content of 2-Oxoacids in Rat Brain Extracts Using High-Performance Liquid Chromatography

2-Oxoacids are involved in a number of important metabolic processes and can be used as biomarkers in some human diseases. A new optimized method for quantification of 2,4-dinitrophenylhydrazine derivatives of 2-oxoacids using high-performance liquid chromatography was developed based on available techniques for quantification of 2-oxoacids in mammalian brain. The use of the 2,4-dinitrophenylhydrazine derivatives of 2-oxoacids was shown to be more advantageous in comparison with the previously used phenylhydrazine derivatives, due to a high chemical stability of the former. Here, we determined the concentrations of pyruvate, glyoxylate, 2-oxoglutarate, 2-oxomalonate, and 4-methylthio-2-oxobutyrate in the methanol/acetic acid extracts of the rat brain using the developed method, as well discussed the procedures for the sample preparation in analysis of mammalian brain extracts. The validation parameters of the method demonstrated that the quantification limits for each of the analyzed of 2-oxoacids was 2 nmol/mg tissue. The developed method facilitates identification of subtle changes in the tissue and cellular content of 2-oxoacids as (patho)physiological biomarkers of metabolism in mammalian tissues.

WDR76 Promotes MLL-Rearranged Leukemia Via Selective Recognition of 5-Hydroxymethylcytosine in DNA

Although rare, the distribution of the 5-hydroxymethylcytosine (hmC) modification in mammalian DNA is tissue- and gene-specific, yet distinct from its transcriptionally-repressive methylcytosine (mC) precursor, suggesting unique signaling potential. To examine this possibility, we fractionated mammalian brain extracts to discover binding partners specific for oxidized states of mC. We demonstrate that one such factor, WDR76, is a highly hmC-specific binding protein that modulates gene expression within chromosomal regions enriched in hmC where it binds. We demonstrate direct transcriptional activation of several target genes in mouse embryonic stem cells as a function of hmC levels and contingent upon WDR76. In human cell lines and mouse models, WDR76 recruitment by hmC is critical for the initiation and maintenance of MLL-rearranged leukemias. Beyond its canonical role as an intermediate in mC remediation, we show that hmC can be an epigenetic mark whose recognition drives leukemogenesis, portending analogous signaling pathways for other rare DNA modifications.

Analysis of Free Amino Acids in Mammalian Brain Extracts.

An optimized method for analysis of free amino acids using a modified lithium-citrate buffer system with a Hitachi L-8800 amino acid analyzer is described. It demonstrates clear advantages over the sodium-citrate buffer system commonly used for the analysis of protein hydrolysates. A sample pretreatment technique for amino acid analysis of brain extracts is also discussed. The focus has been placed on the possibility of quantitative determination of the reduced form of glutathione (GSH) with simultaneous analysis of all other amino acids in brain extracts. The method was validated and calibration coefficient (KGSH) was determined. Examples of chromatographic separation of free amino acids in extracts derived from different parts of the brain are presented.

Intracellular and non-neuronal targets of voltage-gated potassium channel complex antibodies

ObjectivesAutoantibodies against the extracellular domains of the voltage-gated potassium channel (VGKC) complex proteins, leucine-rich glioma-inactivated 1 (LGI1) and contactin-associated protein-2 (CASPR2), are found in patients with limbic encephalitis, faciobrachial dystonic...

Amyloid precursor protein 695 associates with assembled NR2A‐ and NR2B‐containing NMDA receptors to result in the enhancement of their cell surface delivery

This is a study of the interaction between the two NMDA neurotransmitter receptor subtypes, NR1/NR2A and NR1/NR2B, and amyloid precursor protein (APP) 695, the major APP variant expressed in neurones. APP695 co-immunoprecipitated with assembled NR1-1a/NR2A and NR1-1a/NR2B NMDA receptors following expression in mammalian cells. Single NR1-1a, NR1-2a, NR1-4b(c-Myc), or NR2 subunit transfections revealed that co-association of APP695 with assembled NMDA receptors was mediated via the NR1 subunit; it was independent of the NR1 C1, C2, and C2' cassettes and, the use of an NR1-2a(c-Myc)-trafficking mutant suggested that interaction between the two proteins occurs in the endoplasmic reticulum. The use of antibodies directed against extracellular and intracellular NR2 subunit epitopes for immunoprecipitations suggested that APP/NMDA receptor association was mediated via N-terminal domains. Anti-APP antibodies immunoprecipitated NR1, NR2A, and NR2B immunoreactive bands from detergent extracts of mammalian brain; reciprocally, anti-NR1 or anti-NR2A antibodies co-immunoprecipitated APP immunoreactivity. Immune pellets from brain were sensitive to endoglycosidase H suggesting that, as for heterologous expression, APP and NMDA receptor association occurs in the endoplasmic reticulum. Co-expression of APP695 in mammalian cells resulted in enhanced cell surface expression of both NR1-1a/NR2A and NR1-1a/NR2B NMDA receptors with no increase in total subunit expression. These findings are further evidence for a role of APP in intracellular trafficking mechanisms. Further, they provide a link between two major brain proteins that have both been implicated in Alzheimer's disease.

Purification and structure of neurostatin, an inhibitor of astrocyte division of mammalian brain.

Neurostatin was originally described as an inhibitor of astroblast and astrocytoma division present in rat brain extracts and immunologically related to the sugar moiety of epidermal growth factor receptor and to blood group antigens. It was purified recently from mammalian brain extracts and characterized as a glycosphingolipid, but its precise structure remained unknown. Neurostatin has now been purified to apparent homogeneity from ganglioside extracts of rat, bovine, and porcine brain. It is cytostatic for astroblasts, C6 glioma cells, and various human astrocytomas grades III and IV, with IC(50) values ranging from 250 to 450 nM, but does not affect the division of primary or transformed fibroblasts up to concentrations >4 microM. Matrix-assisted laser desorption ionization time-of-flight mass spectrometry of purified pig neurostatin showed a molecular ion of 1, 905 Da and ions of 1,863 and 1,934 Da, compatible with a disialoganglioside. Mono- and bidimensional NMR spectra, together with biochemical studies, suggest that neurostatin may be the 9-O-monoacetyl ester of GD1b.

Control of glial number: Purification from mammalian brain extracts of an inhibitor of astrocyte division

Inhibitors of astrocyte cell division, immunologically related to the sugar moiety of epidermal growth factor receptor and to blood group antigens, have been purified from mammalian brain extracts. Mass spectra, high resolution proton magnetic resonance spectra, and chemical and enzymic analysis of the purified fraction indicated that the compounds isolated were glycosphingolipids, although signals compatible with the presence of aminoacid residues were also observed. Lectin binding indicated the presence of NAc-Neuraminic acid, NAc-glucosamine, fucose, galactose, and glucose. The inhibitor was cytostatic for astrocytes, C6 glioma cells, and endothelial cells, with approximate ID50 of 250 nM. Primary cultures of fibroblasts or 3T3 cells were not affected up to concentrations of 800 nM. Concentrations of the inhibitor of 800 nM or higher, caused non-specific cytotoxicity. The biological and immunological properties of this brain inhibitor were identical to those of the EGF receptor-related inhibitor previously described with the acronym ERI. Because of its source and cytostatic action, the glial inhibitor has been renamed neurostatin. Rabbit antibodies to neurostatin immunostained astrocytes and neurons, both in culture and in tissue sections.

Demonstration and partial characterization of protein kinase C in crude extracts of the cestode Hymenolepis diminuta

The presence of a kinase with the activation characteristics of protein kinase C (PKC) was demonstrated in supernatants of homogenates of the cestode Hymenolepis diminuta. Maximal phosphorylation activity was observed in diluted supernatants in the presence of Ca 2+, phosphatidylserine and β-phorbol-12-myristate-13-acetate (PMA), whereas α-PMA was inactive. PKC-like activation in tissue slice extracts was abrogated by prior treatment of tissue slices with staurosporine. Specific activity of H. diminuta PKC was low compared with that of mammalian brain extracts but similar to that of other invertebrates. The present study demonstrates the presence of a kinase activity in H. diminuta that possesses activation and inhibition characteristics similar to the α-, β-, and γ-isomers of mammalian PKC.

Metabolic Alterations in Brain Autopsies: Proton NMR Identification of Free Glycerol

Metabolic alterations in bovine brain homogenate were examined as a function of post mortem interval (PMI) using high-resolution proton NMR spectroscopy. In particular, while lactate, glutamate, glutamine, creatine and inositols as well as the total concentration of trimethyl-ammonium compounds remained constant, prominent changes due to the hydrolysis of N-acetylaspartate to acetate and aspartate as well as the decomposition of glycerophosphocholine into free choline and glycerol correlated linearly with the duration of PMI (3–195 h). The spectroscopic identification of the latter process was confirmed by proton NMR studies of model solutions as well as of extracts of mammalian brain showing high levels of free glycerol. Since the methylene resonances of glycerol overlap with the proton resonances of myo-inositol, care should be taken in the interpretation of both in vitro and in vivo brain spectra.

Metabolic alterations in brain autopsies: proton NMR identification of free glycerol.

Metabolic alterations in bovine brain homogenate were examined as a function of post mortem interval (PMI) using high-resolution proton NMR spectroscopy. In particular, while lactate, glutamate, glutamine, creatine and inositols as well as the total concentration of trimethyl-ammonium compounds remained constant, prominent changes due to the hydrolysis of N-acetylaspartate to acetate and aspartate as well as the decomposition of glycerophosphocholine into free choline and glycerol correlated linearly with the duration of PMI (3-195 h). The spectroscopic identification of the latter process was confirmed by proton NMR studies of model solutions as well as of extracts of mammalian brain showing high levels of free glycerol. Since the methylene resonances of glycerol overlap with the proton resonances of myo-inositol, care should be taken in the interpretation of both in vitro and in vivo brain spectra.

PH-dependent solubility and assembly of microtubules in bovine brain extracts.

Alkaline pH favors the assembly of microtubules (MTs) in marine egg extracts [Suprenant and Marsh, 1987: J. Cell Sci. 184:167-180; Suprenant, 1989: Exp. Cell Res. 184:167-180; 1991: Cell Motil. Cytoskeleton 19:207-220] and mammalian brain extracts [Tiwari and Suprenant, 1993: Anal. Biochem. 215:96-103], even though the assembly of purified microtubule protein (MTP) from both of these sources is favored at slightly acidic pH. The present investigation examines whether alkaline pH has a direct or indirect effect on MT nucleation and growth in soluble brain extracts. Cell-free extracts were prepared from bovine cerebral cortex, and a nucleated assembly assay was used to demonstrate that MT assembly in brain extracts is favored at slightly acidic pH. The increase in MT mass found at alkaline pH is due to an increase in the solubility of tubulin not an increase in the extent of assembly. On average, 47.7 +/- 11.3% of the total tubulin is soluble at pH 7.2, while only 30.9 +/- 8.9% of the tubulin is soluble at pH 6.8. A model is proposed that indicates how microtubule proteins from both mammalian brain and marine eggs may be associated with pH-dependent factors.

Measurement of kynurenic acid in mammalian brain extracts and cerebrospinal fluid by high-performance liquid chromatography with fluorometric and coulometric electrode array detection

Kynurenic acid is a broad-spectrum excitatory amino acid (EAA) receptor antagonist which is present in the mammalian central nervous system. We describe a method for the measurement of kynurenic acid using isocratic reverse-phase high-performance liquid chromatography (HPLC) with fluorometric detection enhanced by Zn 2+ as a postcolumn reagent. The method requires no prior sample preparation procedures other than extraction with 0.1 m HClO 4. The reliability of the primary fluorometric method was verified by comparing measurements of tissue concentrations of kynurenic acid in human cerebral cortex and putamen using three different methods of separation with fluorometric detection, as well as four methods utilizing HPLC with coulometric electrode array system (CEAS) detection. All seven methods produced comparable results. The concentration of kynurenic acid in human cerebral cortex was 2.07 ± 0.61 pmol/mg protein, and in human putamen, 3.38 ± 0.81 pmol/mg protein. Kynurenic acid was also found to be present in human cerebrospinal fluid (CSF) at a concentration of 5.09 ± 1.04 n m. The regional distribution of kynurenic acid in the rat brain was examined. Kynurenic acid concentrations were highest in brainstem (149.6 fmol/mg protein) and olfactory bulb (103.9 fmol/mg protein) and lowest in thalamus (26.0 fmol/mg protein). There were no significant postmortem changes in kynurenic acid concentrations in cerebral cortex, hippocampus, and striatum at intervals ranging from 0 to 24 h. Perfusion of the cerebral vasculature with normal saline prior to sacrifice did not significantly alter kynurenic acid content in rat hippocampus, cerebral cortex, or striatum. The analytical methods described are the most sensitive (10–30 fmol injection −1) and specific (utilizing both excitation and emissions properties and electrochemical reaction potentials, respectively) methods for determining kynurenic acid in brain tissue extracts and CSF. These methods should prove useful in examining whether kynurenic acid modulates EAA-mediated neurotransmission under physiologic conditions, as well as in determining the role of kynurenic acid in excitotoxic neuronal death.

Development and survival of neurons in dissociated fetal mesencephalic serum-free cell cultures: I. Effects of cell density and of an adult mammalian striatal-derived neuronotrophic factor (SDNF)

The use of CNS cultures for detection and quantification of neuronotrophic activity in the CNS has been analyzed. In particular the development, i.e., neurotransmitter uptake characteristics, and survival of dopaminergic and GABAergic neurons in fetal mouse (E13)-dissociated mesencephalic cells cultured in serum-free, hormone-supplemented medium have been assessed as a function of culture time and cell density. At all times, more than 98% of the cells were classified as neurons on the basis of immunocytochemical criteria. Results indicate that the increase of cell density in vitro significantly enhances specific high-affinity dopamine uptake per dopaminergic cell and cell survival. This effect is not limited to the dopaminergic cells and suggests that the development of neurotransmitter-related traits and cell survival are influenced by cell density-derived trophic signals. The above-mentioned cultures and parameters have also been used to detect neuronotrophic activity in adult mammalian brain extracts or more purified preparations. In particular, bovine striatal extracts contain activity capable of increasing high-affinity neurotransmitter uptake parameters and cell survival of at least the dopaminergic and GABAergic neurons present in the culture system. The neuronotrophic activity from bovine striatum has been partially purified and is associated with a fraction whose main component is a basic protein of approximately 14 kDa.

Purification and characterization of a β-galactoside-binding soluble lectin from rat and bovine brain

A β-galactoside-binding activity has been detected in mammalian brain extracts using a hemagglutination test and a nerve cell aggragation assay. Inhibition studies suggested the involvement of lectin-carbohydrate interactions in these processes. In an attempt to explore further the biological role of brain lectins, the β-galactoside-binding activity has been purified to apparent homogeneity from bovine and rat brain by salt extraction of the brain tissue and affinity chromatography on asialofetuin-agarose. The molecular weights determined by gel filtration, under native conditions on Ultrogel AcA-34, were 30 000 for the bovine brain lectin and 32 000 for the rat brain lectin; polyacrylamide gel electrophoresis in SDS gave molecular weights of 15 000 and 16 000, respectively, suggesting that the two brain lectins are dimers. Both lectins have an isoelectric point of 3.9. Amino acid composition data indicate that both lectins contain high proportions of glycine and acidic amino acids. The lectins are specific for β- D-galactosides and related sugars and the configuration of carbon atoms 1, 2 and 4 seems of primary importance. Moreover, the nerve cell aggregation-promoting activity of the purified lectin is 300-fold that of the crude extracts.

Effects of mammalian brain extracts and chlormadinone acetate on neuronal Na +, K +-ATPase and electrogenic Na +, K +-pump activity in vitro

Acid-acetone extracts of brain (from beef and guinea pig) and chlormadinone acetate (CMA) were compared with ouabain for their ability to inhibit the electrogenic Na +,K +-pump and the Na +,K +-ATPase of neuronal tissues. The membrane potential of neurones in the paravertebral sympathetic ganglion of the bullfrog was recorded in K +-free Ringer's solution by means of the sucrose gap technique. The potassium activated hyperpolarization (K H +), induced by the re-introduction of potassium, was used as an index of electrogenic Na +,K +-pumping. The K H + was blocked by 1 μM ouabain. Na +,K +-ATPase activity was measured in microsomal membrane preparations of frog and beef brain using a continuous spectrophotometric assay. Although ouabain consistently inhibited beef brain Na +,K +-ATPase (IC 50 = 2.2 μM), acid-acetone extracts prepared from guinea pig and beef brain produced only partial inhibition. Neither of the extracts significantly reduced the K H + of the frog ganglion. CMA inhibited Na +,K +-ATPase prepared from bullfrog brain and spinal cord with slightly greater potency (IC 50 = 4.5 μM) than did ouabain (IC 50 = 10 μM). In contrast, electrogenic Na +,K +-pumping (i.e. the K H +) in the frog ganglion was not affected by this steroid. It is concluded that although both the extracts and CMA inhibited Na +,K +-ATPase, neither can be considered ouabain-like due to their failure to affect the electrogenic Na +,K +-pump in situ.

Identification of gastrin releasing peptide-related substances in guinea pig and rat brain

Rat and guinea pig brain extracts were examined for the occurrence of gastrin-releasing peptide (GRP)-like substances by sequence specific radioimmunoassays interfaced with gel filtration and reversed phase high performance liquid chromatography (RP-HPLC). Tryptic digestion of the immunoreactive peptides followed by RP-HPLC was used to further characterize GRP-related peptides in brain. Using these analytical techniques it was found that guinea pig brain extracts contained a peptide with characteristics identical to authentic GRP (27 amino acid residues long). A carboxyterminal fragment with the characteristics of GRP(18–27) as well as a respective aminoterminal fragment with the characteristics of GRP(1–16) were also present in guinea pig brain extracts. The GRP(18–27) seems to correspond to the bombesin related material that has been described previously in mammalian brain extracts. Rat brain extracts also contained a peptide with the characteristics of GRP(18–27). The corresponding aminoterminal fragment, however, behaved differently on RP-HPLC from authentic GRP(1–16) and it was not recognized by antibodies directed to the aminoterminal tridecapeptide fragment of authentic GRP. Similarly the GRP-like peptide from rat brain did not comigrate on RP-HPLC with authentic GRP and was unreactive to antibodies directed toward the aminoterminus of GRP.

Factor I and GABA: Resolution of a long-standing problem

1. 1. Factor I, the inhibitory agent(s) present in certain nerve extracts which is responsible for the inhibition of crayfish stretch receptor neurones, is up to 300 times more effective than can be accounted for by the contained γ-aminobutyric acid (GABA). 2. 2. The inhibition caused by extracts of crab nerves is almost exclusively due to amino acids (aspartate, glutamate, taurine) other than GABA, except in the case of extracts of isolated inhibitory axons. 3. 3. The sensitivity of stretch receptor neurones to aspartate, glutamate and taurine varies independently from that to GABA. As a result of this, there are great quantitative variations in the inhibitory effects of nerve extracts. 4. 4. The mechanism of action of aspartate, glutamate and taurine appears to be the same as that of GABA: all these amino acids activate Cl channels and their action can be blocked by picrotoxin. 5. 5. When tested on the isolated hindgut of the vas deferens of crayfish, aspartate, glutamate and taurine can act like GABA. 6. 6. Extracts of mammalian brain contain a far greater proportion of GABA than do crustacean nerve extracts. GABA thus accounts for about 35 per cent of the inhibitory effect of the brain extracts. Aspartate, glutamate and taurine account for another 30 per cent. The remainder-according to other authors-is due to guanidino compounds, possibly also to γ-amino-β-hydroxybutyric acid. 7. 7. An extensive discussion resolves apparent contradictions in the literature concerning the identity and significance of Factor I, and its relation to GABA.

Immunochemical and immunofluorescence studies of the glial fibrillary acidic protein in vertebrates

Phosphate buffer extracts (pH 8.0) of the brain and the spinal cord of various vertebrates, mammalian and submammalian, cross-reacted with antihuman glial fibrillary acidic (GFA) protein serum by Ouchterlony double diffusion. Mammalian brain extracts, as previously reported, gave an immunodiffusion pattern of complete identity with human GFA protein. In submammalian vertebrates (shark, goldfish, turtle and chicken) strong spurs were observed at the junction with human GFA protein, suggesting incomplete identity. GFA protein from mammalian and submammalian vertebrates had the same extraction properties, immunoelectrophoretic mobility and molecular weight as human GFA protein. By immunofluorescence with antihuman GFA protein, serum astrocytes were selectively stained in cryostat sections of the brain and the spinal cord in all vertebrates studied, mammalian and submammalian, with the exception of the lamprey. No immunofluorescence was observed in invertebrate ganglia. Some antomical observations on the astrocytic framework of various vertebrates, as observed with immunofluorescence, are reported.

Simple Peptides In Brain

Although polypeptides such as substance P and related compounds, neurohypophyseal hormones, and the releasing factors of the anterior hypothalamus have been the subjects of extensive studies in the past decade, relatively few studies have been made of the occurrence of smaller oligopeptides in the brain and of their possible function. Automatic amino acid analysis of protein-free extracts of mammalian brain demonstrated the presence of unknown ninhydrin-positive compounds, which disappeared after acid hydrolysis. The nomenclature of the di- and tripeptides is ambiguous. Their classification as di- or tripeptides as a group may be justified because naturally occurring peptides can be separated grossly into three classes: (1) di- or tripeptides, (2) biologically active peptides having 7-15 amino acid residues, which include most peptide hormones and antibiotics, and (3) the larger polypeptides, which have very diverse biological functions. This chapter describes the occurrence, distribution, and metabolism of oligopeptides, which are found in the mammalian brain up to the present time. The physiological and pharmacological actions of some of them and of compounds related to them also arediscussed, although unfortunately there is almost nothing known about this.

Analysis of slow inhibitory postsynaptic potential of bullfrog sympathetic ganglion.

Analysis of slow inhibitory postsynaptic potential of bullfrog sympathetic ganglion.S Nishi, and K KoketsuS Nishi, and K KoketsuPublished Online:01 Sep 1968https://doi.org/10.1152/jn.1968.31.5.717MoreSectionsPDF (2 MB)Download PDF ToolsExport citationAdd to favoritesGet permissionsTrack citations ShareShare onFacebookTwitterLinkedInWeChat Previous Back to Top Next Download PDF FiguresReferencesRelatedInformation Cited ByPeptide-Mediated Neurotransmission Takes Center StageTrends in Neurosciences, Vol. 41, No. 6Amphibian sympathetic ganglia: An owner's and operator's manualProgress in Neurobiology, Vol. 43, No. 4-5Antagonists discriminate muscarinic excitation and inhibition in sympathetic ganglionBrain Research, Vol. 400, No. 1Effects of mammalian brain extracts and chlormadinone acetate on neuronal Na+, K+-ATPase and electrogenic Na+, K+-pump activity in vitroBrain Research, Vol. 344, No. 1Characterization of long-lasting histaminergic inhibition in a beating pacemaker neuron of OnchidiumBrain Research, Vol. 332, No. 1Effects of kynurenate on root potentials evoked by synaptic activity and amino acids in the frog spinal cordBrain Research, Vol. 330, No. 2Post-stimulus hyperpolarization in retzius nerve cells of leech, Haemopis sanguisugaComparative Biochemistry and Physiology Part A: Physiology, Vol. 82, No. 4Electrophysiological effects of peptides derived from pro-opiomelanocortinPharmacology & Therapeutics, Vol. 24, No. 1Acetylcholine-induced electrical responses in neuroblastoma cellsNeuroscience, Vol. 8, No. 3The effect of α-, β adrenergic receptor agonists and antagonists on the efflux of 22Na and uptake of 42K by rat brain cortical slicesBrain Research, Vol. 236, No. 1A critical evaluation of the use of toxins fromDendro- aspis viridis to block nicotinic responses at central and ganglionic synapsesBrain Research, Vol. 209, No. 1Excitatory and inhibitory effects of histamine on molluscan neuronsBrain Research, Vol. 196, No. 1Alpha-adrenoceptor and dopamine receptor antagonists do not block the slow inhibitory postsynaptic potential in sympathetic gangliaBrain Research, Vol. 187, No. 1Slow inhibitory postsynaptic potentials and hyperpolarization evoked by noradrenaline in the neurones of mammalian sympathetic ganglionJournal of the Autonomic Nervous System, Vol. 1, No. 3Effects of ACTH4–;10 on synaptic transmission in frog sympathetic ganglionEuropean Journal of Pharmacology, Vol. 57, No. 4Receptor-mediated noradrenaline stimulation of (Na+-K+) ATPase in rat brain cortical homogenatesGeneral Pharmacology: The Vascular System, Vol. 10, No. 3Roles of electrogenic Na+ pump and K+ conductance in the slow inhibitory postsynaptic potential of bullfrog sympathetic ganglion cellsLife Sciences, Vol. 23, No. 24Synaptic events in sympathetic gangliaProgress in Neurobiology, Vol. 11, No. 2Effects of noradrenaline and serotonin on activity of single lateral and medial geniculate neuronsGeneral Pharmacology: The Vascular System, Vol. 9, No. 6Different sensitivities of acetylcholine-induced “after-hyperpolarization” compared to dopamine-induced hyperpolarization, to ouabain or to lithium-replacement of sodium, in rabbit sympathetic gangliaLife Sciences, Vol. 20, No. 11Acceleration of the electrogenic Na+ pump by adrenaline in frog skeletal muscle fibresLife Sciences, Vol. 19, No. 7Analysis of amino acid responses on frog motoneuronesNeuropharmacology, Vol. 15, No. 1Unusual cholinergic response of bullfrog sympathetic ganglion cellsEuropean Journal of Pharmacology, Vol. 31, No. 2Ionic mechanism of the slow excitatory postsynaptic potential in bullfrog sympathetic ganglion cellsBrain Research, Vol. 81, No. 2The role of calcium in the central effects of biogenic aminesLife Sciences, Vol. 14, No. 7Slow inhibitory postsynaptic potentials of bullfrog sympathetic ganglia in sodium-free mediaLife Sciences, Vol. 13, No. 5Slow synaptic inhibition: evidence for synaptic inactivation of sodium conductance in sympathetic ganglion cellsBrain Research, Vol. 55, No. 1Acetylcholine and slow synaptic inhibition in frog sympathetic ganglion cellsBrain Research, Vol. 55, No. 1The effect of adrenaline on sympathetic ganglion cells of bullfrogsLife Sciences, Vol. 11, No. 24A functional connection between postganglionic neurons in a bullfrog sympathetic ganglionLife Sciences, Vol. 11, No. 17Prolonged conductance increase in thalamic neurons during synchronizing inhibitionBrain Research, Vol. 24, No. 2Post synaptic stimulation of the electrogenic sodium pumpLife Sciences, Vol. 8, No. 5 More from this issue > Volume 31Issue 5September 1968Pages 717-28 https://doi.org/10.1152/jn.1968.31.5.717PubMed4304051History Published online 1 September 1968 Published in print 1 September 1968 Metrics