Studies on catecholamines and 5-hydroxytryptamine and the significance of their metabolites in animal tissues and body fluids

The papers presented in this thesis describe the development of methods for the estimation of adrenaline, noradrenaline, dopamine, 5-hydroxytryptamine and some of their metabolites and the application of such estimations to some problems of biological interest. The major part of the thesis is concerned with the metabolism of these amines in the mammalian central nervous system. The papers are presented in three groups.The first group is made up of papers in which the estimation of 5-hydroxytryptamine (5-HT) or its metabolite 5-hydroxy-indol-3-yl acetic acid (5-HIAA) was measured.1. On the question of the occurrence and metabolism of 5-hydroxy-tryptamine and related indole compounds in mammalian semen. By T. Mann, R. P. Seamark and D. F. Sharman. Br. J. Pharmac. Chemother. 17, 208 - 217, 1961.In this paper it was shown conclusively that the semen of man, bull, boar, ram and dog contains little or no 5-hydroxytryptamine.2. Drug-induced changes in the concentration of 5-0R indolyl compounds in cerebrospinal fluid and caudate nucleus. By G. V. Ashcroft and D. P. Sharman. Br. J. Pharmac. Chemother. 19. 155 - 160, 1962.Because of an earlier observation by Ashcroft and Sharman (Nature, Lond.,186, 1050 - 1051, i960) that the cerebrospinal fluid of depressed patients contained a lower concentration of 5-hydroxyindolyl compounds than normal, the effect of reserpine, a drug known to reduce the concentration of 5-hydroxytryptamine in the brain, on the concentration of such compounds in the cerebrospinal fluid of the dog was examined. It was found that the concentration of 5-hydroxyindolyl compounds in the cerebrospinal fluid was increased after reserpine.3. The effect of a-methyldopa on the metabolism of 5-hydroxy-tryptamine in rat brain. By D. P. Sharman and S. E. Smith. J. Neurochem. 403 - 406, 1962.In this paper, the concentration of 5-HIAA in the brain was used as an index of the rate at which 5-HT was released in this tissue after a-methyldopa, an inhibitor of the formation of 5-HT,was given to rats.4. The action of 2-aminotetralin ({3-tetrahydronaphthylamine) on the metabolism of 5-hydroxytryptamine in the brain of the mouse. By D. Robinson and D. P. Sharman. Br. J. Pharmao. Chemother. 29. 535 - 341, 1967.2-Aminotetralin causes a reduction in the concentration of 5- hydroxyindol-3-ylacetic acid in the brain of the mouse (paper 12). The possible causes of this effect were' examined.The second group consists mainly of papers which describe the development of methods of estimating dopamine and its acid metabolites 3,4-dihydroxyphenylacetio acid (DOPAC) and 4-hydroxy-3-methoxyphenyl acetic acid (homovanillic acidj HVA), their application to several problems, chiefly to a study of the rate of utilisation of dopamine in the brain and also the effect of drugs on the metabolism of this amine.5. Chemical and physiological changes produced by arterial infusion of dihydroxyphenylalanine into one cerebral hemisphere of the cat. By R. Dagirmanjian, R. Laverty, P. Mantegazzini, D. P. Sharman and M. Vogt. J. Neurochem. 10, 177 - 182, 1965.The infusion of 3,4-dihydroxyphenylalanine (DOPA) into one carotid artery of the cat can cause arousal of the brain on the side of the infusion. It was shown that this unilateral arousal is accompanied by an increase in the concentration of dopamine in the caudate nucleus, hypothalamus and midbrain reticular formation on the same side of the brain.6. The subcellular localisation of dopamine and acetylcholine in the dog caudate nucleus. By R. Laverty, I. A. Michaelson, D.P. Sharman and V. P. Whittaker. Br. J. Pharmac. Chemother. 21, 482 - 490, 1963.7. Localisation of acetylcholine, 5-hydroxytryptamine and noradrenaline within subcellular particles derived from guinea-pig subcortical brain tissue. By I. A. Michaelson, V. P. Whittaker, R. Laverty and D. P. Sharman. Biochem. Pharmacol. 12. 1450-1453, 1963.8. A fluorimetric method for the estimation ti 4-hydroxy-3-methoxyphenylacetic acid (homovanillic acid) and its identification in brain tissue. By D. F. Sharman. Br. J. Pharinac. Chemother. 20. 204 - 213, 1963.9. The estimation of small quantities of 3,4-dihydroxyphenylethylamine in tissues. By R. Laverty and D. F. Sharman. Br. J. Pharmac. Chemother. 24, 538 - 548, 1965.10. Modification by drugs of the metabolism of 3,4-dihydroxyphenylethylamine, noradrenaline and 5-hydroxytryptamine in the brain. By R. Laverty and D. F. Sharraan. Br. J. Pharmac. Chemother. 24. 759 - 772, 1965.11. The effect of drugs on the homovanillie aoid content of the corpus striatum of some rodents. By A. V. Juorio, D. F. Sharman and T. Trajkov. Br. J. Pharmac. Chemother. 26. 385 - 392, 1966.12. Changes in the metabolism of 3,4-dihydroxyphenylethylamine (dopamine) in the striatum of the mouse induced by drugs. By D. F. Sharman, Br. J. Pharmac. Chemother. 28. 153 - 163, 1966.13. A discussion of the modes of action of drugs which increase the concentration of 4-hydroxy-3-methoxyphenylacetic acid (homovanillic acid) in the striatum of the mouse. By D. P. Sharman. Br. J. Pharmac. Chemother. 30, 620 - 626, 1967.14. Homovanillic acid and dihydroxyphenylacetic acid in the striatum of monkeys with brain lesions. By D. P. Sharman, L. J. Poirier, G. P. Murphy and T. L. Sourkes. Can. J. Physiol. Pharmacol. 49. 57 - 62, 1967.15. Release by tubocurarine of dopamine and homovanillic acid from the superfused caudate nucleus. By P. J. Portig, D. P. Sharman and Marthe Vogt. J. Physiol. Lond. 194. 565 - 572, 1968.16. The effect of tropolone on the formation of 3,4-dihydroxyphenylacetic acid and 4-hydroxy-3-methoxyphenylacetic acid in the brain of the mouse. By G. P. Murphy, D. Robinson and D. P. Sharman. Br. J. Pharmac. Chemother. j>6, 107 - 115, 1969.17. Turnover of amines using probenecid to block the egress of metabolites. By D. P. Sharman. Metabolism of brain amines. Edited by G. Hooper, Macmillan, London, pp. 34 - 37, 1969.These papers form the main part of the thesis and attempt to relate the concentration of HVA in the central nervous system to the rate at which dopamine is utilised in this tissue. The locus of the metabolism of dopamine in the central nervous system is discussed.The papers in the third group are concerned with noradrenaline or its glycol metabolites.18. Noradrenaline content in the heart and spleen of the mouse tinder normal conditions and after administration of some drugs. By D. P. Sharman, S. Vanov and Marthe Vogt. Br. J. Pharmac. Chemother. 11, 527 - 533, 1962.This study was made to investigate a report of what appeared to he unusual behaviour of the tissue catecholamines in the mouse. The method used to estimate the noradrenaline was designed to incorporate as many controls as was possible to ensure that correct estimates were obtained. The earlier report could not be confirmed.19. Iontophoretic release of adrenaline noradrenaline and 5-hydroxytryptamine from raicropipettes. By K. Krnjevic, R. Laverty and D. P. Sharman. Br. J. Pharmac. Chemother. 20, 491 - 496, 1963.Fluorimetric methods were used to measure the relation between the release of these amines and the electrical charge applied to micropipettes used for the iontophoretic application of drugs to single neurones.20. The action of 2,4,5-trihydroxyphenylethylamine on the storage and release of noradrenaline. By R. Laverty, D. P. Sharman and Marthe Vogt. Br. J. Pharmac. Chemother. 24, 549 - 560, 1965.2,4,5-Trihydroxyphenylethylamine causes a rapid and long lasting depletion of noradrenaline from the mouse heart. A new method was developed for the estimation of the former amine and was used to show that it did not persist in the tissue or was tightly bound in the tissue.21. The noradrenaline content of the caudate nucleus of the rabbit. By D. P. Sharman and Marthe Vogt. J. Neurochem. 12. 62, 1965.This short paper illustrates a frequently reported erroneous result when a commonly used fluorimetric method for the estimation of nor-adrenaline is applied to those brain tissues which contain very little of this amine.22. Gas chromatographic evidence for the presence of glycol metabolites of catecholamines in brain tissue. By B. F. Sharman. J. Physiol. Lond. 200. 35 - 35P, 1969.23. Glycol metabolites of noradrenaline in brain tissue. By D. P. Sharman. Accepted for publication by Br. J. Pharmac. Chemother. 1969.The application of gas liquid chromatography and electron capture detection to the estimation of glycol metabolites of noradrenaline in the brain is described. The possibility of using a similar technique for the estimation of noradrenaline and normetanephrine is discussed.These two papers describe the estimation of noradrenaline, dopamine, 5-hydroxytryptamine and acetylcholine in particles obtained by sub-cellular fractionation of brain tissues. The first shows that dopamine is associated with a particle that is similar to,but distinguish¬ able from, that with which acetylcholine is associated. The second paper demonstrates that the storage sites within subcellular particles for acetylcholine and those for noradrenaline and 5-hydroxytryptamine are different