826
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Bowery NG, Brown DA. Depolarization of isolated rat ganglia by -aminobutyric acid and related compounds. Br J Pharmacol 1972; 45:160P-161P. [PMID: 5041477 PMCID: PMC1666205] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
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827
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Brown DA, Scholfield CN. Nicotine washout rates from isolated rat ganglia in relation to recovery from nicotine depolarization. Br J Pharmacol 1972; 45:29-36. [PMID: 5041505 PMCID: PMC1666184 DOI: 10.1111/j.1476-5381.1972.tb09573.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
1. Isolated rat superior cervical ganglia recovered more slowly from the depolarizing action of nicotine than from that of carbachol or acetylcholine. This was due to sustained high nicotine concentrations in the vicinity of the receptors, since recovery was hastened by adding hexamethonium to the washout fluid.2. Ganglia incubated for 4 min in 80 muM (3)H-nicotine accumulated nicotine to a level exceeding the extracellular space, as judged from the uptake of (3)H-mannitol.3. The subsequent efflux of (3)H-nicotine into non-radioactive solution could be largely resolved into two exponential components, with rate constants of 0.55+/-0.04 and 0.094+/-0.007 min(-1). The former was similar to that for total mannitol efflux, and so might be largely ascribed to clearance of extracellular nicotine. The slower efflux might be due to clearance from intracellular compartments. Nicotine efflux rates were not affected by hexamethonium indicating that receptor-activation did not modify the slow efflux.4. Efflux of choline compounds ((3)H-acetylcholine, (3)H-choline and (3)H-carbachol) showed an additional, very slow component (rate constant 0.001 to 0.002 min(-1)).5. It was suggested that slow efflux of intracellular nicotine might sustain depolarization on washing by maintaining high perineuronal concentrations of nicotine. With choline compounds the efflux rate from such sources may be too slow to affect perineuronal concentrations.
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828
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Singh H, Boyd E, Hutton MM, Wilkinson PC, Brown DA, Ferguson-Smith MA. Chromosomal mutation in bone-marrow as cause of acquired granulomatous disease and refractory macrocytic anaemia. Lancet 1972; 1:873-9. [PMID: 4111829 DOI: 10.1016/s0140-6736(72)90741-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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829
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Brown DA, Brownstein MJ, Scholfield CN. Origin of the after-hyperpolarization that follows removal of depolarizing agents from the isolated superior cervical ganglion of the rat. Br J Pharmacol 1972; 44:651-71. [PMID: 4625268 PMCID: PMC1665991 DOI: 10.1111/j.1476-5381.1972.tb07305.x] [Citation(s) in RCA: 53] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
1. Potential changes in isolated rat superior cervical ganglia following addition and removal of depolarizing agents were recorded using a moving-fluid extracellular electrode system.2. Ganglionic negativity produced by carbachol was followed by a pronounced ganglionic positivity on washing. This after-positivity was attributed to hyperpolarization of the ganglion cells since it was unaffected by crushing the postganglionic trunk.3. The after-hyperpolarization was selectively depressed by (a) cooling (Q(10) 2.3), (b) metabolic inhibitors (cyanide, azide, 2,4-dinitrophenol), (c) reducing [K(+)](o) or substituting Cs(+) for K(+), (d) ouabain, and (e) substituting Li(+) for Na(+). This suggested a close dependence on active Na(+) transport.4. When K(+) was restored to K(+)-free solution, or the preparation was warmed rapidly, or when metabolic inhibitors were washed away, the hyperpolarization was rapidly regenerated. The effect of restoring K(+) indicated that the hyperpolarization was generated directly by the Na(+) pump.5. The hyperpolarization was not altered by replacing Cl(-) with isethionate, indicating that the voltage change produced by the Na(+) current was not modified by passive Cl(-) movements.6. Hexamethonium added to the washout fluid augmented the after-hyperpolarization, suggesting that there was a high (cationic) leak current due to continued receptor-activation on washing with normal Krebs solution.7. The hyperpolarization was reduced by omission of Ca(2+) and restored by addition of Mg(2+). This was considered to result from changes in passive membrane permeability.8. The time-course of post-carbachol hyperpolarization accorded with a Na(+) extrusion process whose rate was directly proportional to [Na(+)](i) with a rate constant of 0.38+/-0.02 min(-1) at 23-27 degrees C.9. With increasing concentrations of carbachol, the amplitude of the hyperpolarization increased in proportion to the preceding depolarization, but the rate constant of the hyperpolarization was unchanged.
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830
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Turner B, Brown DA. Amino acid excretion in infancy and early childhood. A survey of 200,000 infants. Med J Aust 1972; 1:62-5. [PMID: 5025157] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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831
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Bowery NG, Brown DA. Observations on ( 3 H) -aminobutyric acid accumulation and efflux in isolated sympathetic ganglia. J Physiol 1971; 218 Suppl:32P-33P. [PMID: 5130619] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
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832
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Steward EG, Player R, Quilliam JP, Brown DA, Pringle MJ. Molecular conformation of GABA. NATURE: NEW BIOLOGY 1971; 233:87-8. [PMID: 5287002 DOI: 10.1038/newbio233087a0] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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833
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Brown DA, Halliwell JV, Scholfield CN. Uptake of nicotine and extracellular space markers by isolated rat ganglia in relation to receptor activation. Br J Pharmacol 1971; 42:100-13. [PMID: 5580695 PMCID: PMC1666984 DOI: 10.1111/j.1476-5381.1971.tb07090.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
1. Uptake of (3)H-nicotine by isolated rat superior cervical sympathetic (SCG) and nodose (NG) ganglia was measured in vitro. Depolarization of the ganglia by nicotine was measured electrically.2. Nicotine depolarized the SCG but not the NG. The mean ED50 for depolarization was 5.3 x 10(-6)M.3. Both ganglia accumulated nicotine when incubated in 3.1 x 10(-5)M(3)H-nicotine: after 30 min incubation the ratios of tissue to medium concentrations were (mean +/- S.E. of mean): SCG, 3.49 +/- 0.13; NG, 2.50 +/- 0.09.4. Total water contents, estimated by drying to constant weight, were: SCG, 83.8 +/- 0.12%; NG, 80.1 +/- 0.21%. Extracellular spaces, measured as (3)H-mannitol space, were: SCG, 38.8 +/- 1.3; NG, 40.3 +/- 0.8% wet weight. These values were not significantly altered by nicotine.5. Correction for tissue fluid spaces indicated that the ratio of the mean intracellular fluid concentration to the extracellular fluid concentration for (3)H-nicotine at 3.1 x 10(-5)M were: SCG, 7.4; NG, 5.6. The ratios were not altered in any consistent manner on varying the nicotine concentration between 3.1 x 10(-7) and 1.6 x 10(-4)M.6. When the nicotine concentration was sufficiently great (6.2 x 10(-6)M or more) to evoke large SCG depolarizations, hexamethonium (2.5 x 10(-3)M) reduced (3)H-nicotine uptake by the SCG by up to 19% without affecting uptake by the NG, and thereby reduced the uptake difference between the two ganglia. With nicotine concentrations <6.2 x 10(-6)M, hexamethonium did not modify uptake by either ganglion.7. It was concluded that nicotine may be concentrated within neurones, and that such intracellular accumulation may be augmented during depolarization induced by nicotine.
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834
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Brown DA, Chambers WJ, Fitzpatrick NJ, Rawlinson RM. Molecular orbital theory of organometallic compounds. Part XII. Nature of metal–metal bonding in some binuclear metal carbonyls. ACTA ACUST UNITED AC 1971. [DOI: 10.1039/j19710000720] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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835
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Brown DA, Sane RT. Kinetics of substitution reactions of halogenopentacarbonyl compounds of rhenium and manganese. ACTA ACUST UNITED AC 1971. [DOI: 10.1039/j19710002088] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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836
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Brown DA, Scholfield CN. Potentials in isolated rat superior cervical ganglia produced by nicotine. Br J Pharmacol 1970; 40:559P-561P. [PMID: 5497821 PMCID: PMC1703196] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
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837
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Elwood PC, Benjamin IT, Fry FA, Eakins JD, Brown DA, De Kock PC, Shah JU. Absorption of iron from chapatti made from wheat flour. Am J Clin Nutr 1970; 23:1267-71. [PMID: 5475656 DOI: 10.1093/ajcn/23.10.1267] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
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838
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Brown DA, Jones KB, Halliwell JV, Quilliam JP. Evidence against a presynaptic action of acetylcholine during ganglionic transmission. Nature 1970; 226:958-9. [PMID: 4315654 DOI: 10.1038/226958a0] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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839
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Brown DA, Halliwell JV, Jones KB, Quilliam JP. An attempt to determine whether acetylcholine can release acetylcholine from a sympathetic ganglion. Br J Pharmacol 1970; 38:446P-448P. [PMID: 5417875 PMCID: PMC1702791] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
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840
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Turner B, Brown DA. Aminoacid excretion in infancy and early childhood. A survey of 100,000 infants. Med J Aust 1970; 1:11-4. [PMID: 5436523] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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841
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A. Brown D, Lyons H, Manning A. A new type of isomerism in some phosphine and phosphite derivatives of the metal carbonyls. Inorganica Chim Acta 1970. [DOI: 10.1016/s0020-1693(00)93320-6] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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842
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Brown DA, Brownstein MJ, Scholfield CN. On the nature of the drug-induced after-hyperpolarization in isolated rat ganglia. Br J Pharmacol 1969; 37:511P-513P. [PMID: 4242361 PMCID: PMC1703645] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
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843
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Brown DA, Halliwell JV, Scholfield CN. Nicotine uptake by isolated rat ganglia. Br J Pharmacol 1969; 37:510P-511P. [PMID: 5348441 PMCID: PMC1703677] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
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844
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845
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Brown DA. Responses of normal and denervated cat superior cervical ganglia to some stimulant compounds. J Physiol 1969; 201:225-36. [PMID: 5773557 PMCID: PMC1351641 DOI: 10.1113/jphysiol.1969.sp008752] [Citation(s) in RCA: 33] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
1. The effect of preganglionic denervation on the sensitivity of the cat superior cervical ganglion to close-arterial injections of some stimulant compounds in vivo has been studied.2. Ganglionic responses were assessed (a) by recording simultaneously ganglion depolarization and post-ganglionic nerve action potential discharges, and (b) by measuring the contractions of the nictitating membrane and applying a correction for the change in sensitivity of the membrane to noradrenaline.3. No change could be detected in the electrical responses of the ganglion to carbachol after denervation.4. Nictitating membrane recording suggested that denervation increased the response of the ganglion to acetylcholine, but had little effect on ganglionic sensitivities to carbachol, nicotine, tetramethylammonium or potassium chloride.5. It was concluded that the neurones of the superior cervical ganglion do not, in general, show any substantial change of sensitivity to cholinesterase-resistant stimulant compounds after denervation. The supersensitivity to acetylcholine is probably the result of a reduction of ganglionic acetylcholinesterase.
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846
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Brown DA, Hoffmann PC, Roth LJ. 3H-Nicotine in cat superior cervical and nodose ganglia after close-arterial injection in vivo. Br J Pharmacol 1969; 35:406-17. [PMID: 5809733 PMCID: PMC1703366 DOI: 10.1111/j.1476-5381.1969.tb08282.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
1. Concentrations of (3)H-nicotine in the superior cervical and nodose ganglia of anaesthetized cats were measured after close-arterial injection.2. Shortly after injection there was a higher concentration of (3)H-nicotine in the superior cervical ganglion than in the nodose ganglion. Mean concentration ratios, superior cervical ganglion/nodose ganglion (S/N ratios) were: 2 min after injection, 1.60 +/- 0.19; 4 min, 1.21 +/- 0.19; 8 min, 0.92 +/- 0.05. These ratios were independent of the dose of nicotine over the range 4 to 200 mug in 0.2 ml.3. There was no comparable difference in the concentrations of injected (14)C-inulin or (3)H(2)O in the two ganglia, or in total water content.4. Procedures which reduced the pharmacological action of nicotine (pre-treatment with hexamethonium, admixture of (14)C-inulin) tended to reduce the S/N ratio for nicotine.5. Autoradiographs showed that nicotine entered the neurones of both superior cervical and nodose ganglia.6. It was concluded that the higher concentration of nicotine in the superior cervical ganglion was probably related to its selective pharmacological action at this site, and may have been due to a greater intracellular retention of nicotine.
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847
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Brown DA, Rawlinson RM. Molecular orbital theory of organometallic compounds. Part XI. Electronic structures of the tricarbonylarenemetals of Group VI. ACTA ACUST UNITED AC 1969. [DOI: 10.1039/j19690001534] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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848
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Brown DA, Rawlinson RM. Molecular orbital theory of organometallic compounds. Part X. Electronic structures of the hexacarbonylmetals of Group VI. ACTA ACUST UNITED AC 1969. [DOI: 10.1039/j19690001530] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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849
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Brown DA, Stumpf WE, Roth LJ. Location of Radioactively Labelled Extracellular Fluid Indicators in Nervous Tissue by Autoradiography. J Cell Sci 1969; 4:265-88. [PMID: 5781597 DOI: 10.1242/jcs.4.1.265] [Citation(s) in RCA: 38] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The location of three radioactively labelled extracellular-space indicators ([3H]methoxyinulin, [3H]-D-mannitol and sodium [35S]sulphate) in the superior cervical sympatmhetic and nodose ganglia of cats was studied using an autoradiographic technique. The technique was designed to eliminate movement of soluble, diffusible substances in tissues after excision, and to provide high autoradiographic resolution. Ganglia were rapidly excised after administration of the radioactive compounds in vivo, and frozen in liquid propane. Frozen sections were cut at -60°C at a thickness of 0.7-0. µ. The frozen sections were freeze-dried, dry-mounted on dried, photographic emulsion-coated microscope slides, and exposed at -15°C until development.
The highest densities of silver grains in the autoradiographs were associated with regions of the tissue containing the greatest amounts of connective tissue. Lowest densities occurred beneath neurons and myelinated nerve fibres. The silver grain density beneath neuron perikarya was between 10% and 15% of that associated with plasma. Attempts were made to determine the source of these subneuronal silver grains. The results suggested that they could not be ascribed to the following: background; chemographs and pressure artefacts; spread of radiation from radioactive material outside the perikarya; and in vitro translocation of radioactive material into the neurons or into the emulsion beneath the neurons. It was concluded that the subneuronal grains reflected a small amount of intraneuronal penetration of the compounds in vivo. There was very little difference between inulin, mannitol and sulphate with regard to the proportion of intracellular activity. Except for this small amount of intracellular radioactivity, the findings accord with the view that inulin, mannitol and sulphate are confined predominantly to the extracellular fluid.
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850
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