Abstract
1. The noradrenaline stores in the sympathetic nerve endings of the cat colon were labelled in vivo with (±)-[7-3H]noradrenaline (500 μc, 11·3 μg) injected 3 hr before killing.
2. The colon was removed and immersed in an organ bath containing Krebs solution. The vascular bed was perfused from the inferior mesenteric artery to the colic vein.
3. The effects of Ca2+, Ba2+ and Mg2+ on the output of [3H]noradrenaline and [3H]metabolites in the venous effluent were measured before and after electrical stimulation of the post-ganglionic inferior mesenteric nerves at 10 impulses/sec.
4. Nerve stimulation increased the efflux of [3H]noradrenaline when the perfusion fluid contained Ca2+. Variations in Ca2+ concentration (1·5-10 mM) did not affect this response.
5. Removal of Ca2+ from the fluid passing through the vascular bed (and therefore from the region of the sympathetic nerve terminals), abolished the output of [3H]noradrenaline in response to nerve stimulation. There was no change when phenoxybenzamine was added to prevent the binding of transmitter on to post-synaptic receptors on the effector organ.
6. The output of transmitter was not changed when Ca2+ was present in the blood vessels of the colon even though it was removed from the solution in contact with the remainder of the tissue.
7. Nerve stimulation released [3H]noradrenaline when Ba2+ was used as a substitute for Ca2+; Mg2+ was not an effective substitute for Ca2+ as then nerve stimulation did not increase the output of radioactive noradrenaline or metabolites.
8. Ba2+ also increased the resting output of [3H]noradrenaline in the absence of nerve stimulation. Addition of Ca2+ or Mg2+ did not change this spontaneous release but it was augmented by removal of Ca2+.
9. It is concluded that Ca2+ is essential for release of the sympathetic transmitter by nerve stimulation but not for the spontaneous output that occurs in the absence of nervous activity. The site of action of Ca2+ is considered to be the terminals of adrenergic fibres.
Full text
PDF














Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- BURN J. H., GIBBONS W. R. THE PART PLAYED BY CALCIUM IN DETERMINING THE RESPONSE TO STIMULATION OF SYMPATHETIC POSTGANGLIONIC FIBRES. Br J Pharmacol Chemother. 1964 Jun;22:540–548. doi: 10.1111/j.1476-5381.1964.tb01708.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- BURNSTOCK G., HOLMAN M. E. Spontaneous potential at sympathetic nerve endings in smooth muscle. J Physiol. 1962 Mar;160:446–460. doi: 10.1113/jphysiol.1962.sp006858. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Boullin D. J., Costa E., Brodie B. B. Apparent depletion of NE stores after repetitive stimulation of cat colon in presence of phenoxybenzamine. Int J Neuropharmacol. 1966 Jul;5(4):293–298. doi: 10.1016/0028-3908(66)90037-2. [DOI] [PubMed] [Google Scholar]
- Burn J. H., Gibbons W. R. The release of noradrenaline from sympathetic fibres in relation to calcium concentration. J Physiol. 1965 Nov;181(1):214–223. doi: 10.1113/jphysiol.1965.sp007756. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Burnstock G., Holman M. E. Junction potentials at adrenergic synapses. Pharmacol Rev. 1966 Mar;18(1):481–493. [PubMed] [Google Scholar]
- Chang C. C., Chang J. C. A change in the subcellular distribution of noradrenaline in the rat isolated vas deferens effected by nerve stimulation. Br J Pharmacol Chemother. 1965 Dec;25(3):758–762. doi: 10.1111/j.1476-5381.1965.tb01798.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Costa E., Boullin D. J., Hammer W., Vogel W., Brodie B. B. Interactions of drugs with adrenergic neurons. Pharmacol Rev. 1966 Mar;18(1):577–597. [PubMed] [Google Scholar]
- DOUGLAS W. W., POISNER A. M. On the mode of action of acetylcholine in evoking adrenal medullary secretion: increased uptake of calcium during the secretory response. J Physiol. 1962 Aug;162:385–392. doi: 10.1113/jphysiol.1962.sp006940. [DOI] [PMC free article] [PubMed] [Google Scholar]
- DOUGLAS W. W., POISNER A. M. Stimulation of uptake of calcium-45 in the adrenal gland by acetylcholine. Nature. 1961 Dec 30;192:1299–1299. doi: 10.1038/1921299a0. [DOI] [PubMed] [Google Scholar]
- DOUGLAS W. W., RUBIN R. P. STIMULANT ACTION OF BARIUM ON THE ADRENAL MEDULLA. Nature. 1964 Jul 18;203:305–307. doi: 10.1038/203305a0. [DOI] [PubMed] [Google Scholar]
- DOUGLAS W. W., RUBIN R. P. THE EFFECTS OF ALKALINE EARTHS AND OTHER DIVALENT CATIONS ON ADRENAL MEDULLARY SECRETION. J Physiol. 1964 Dec;175:231–241. doi: 10.1113/jphysiol.1964.sp007514. [DOI] [PMC free article] [PubMed] [Google Scholar]
- DOUGLAS W. W., RUBIN R. P. The role of calcium in the secretory response of the adrenal medulla to acetylcholine. J Physiol. 1961 Nov;159:40–57. doi: 10.1113/jphysiol.1961.sp006791. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Douglas W. W., Rubin R. P. The mechanism of catecholamine release from the adrenal medulla and the role of calcium in stimulus-secretion coupling. J Physiol. 1963 Jul;167(2):288–310. doi: 10.1113/jphysiol.1963.sp007150. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Douglas W. W. The mechanism of release of catecholamines from the adrenal medulla. Pharmacol Rev. 1966 Mar;18(1):471–480. [PubMed] [Google Scholar]
- GILLESPIE J. S., MACKENNA B. R. The inhibitory action of the sympathetic nerves on the smooth muscle of the rabbit gut, its reversal by reserpine and restoration by catechol amines and by DOPA. J Physiol. 1961 Apr;156:17–34. doi: 10.1113/jphysiol.1961.sp006655. [DOI] [PMC free article] [PubMed] [Google Scholar]
- HERTTING G., AXELROD J. Fate of tritiated noradrenaline at the sympathetic nerve-endings. Nature. 1961 Oct 14;192:172–173. doi: 10.1038/192172a0. [DOI] [PubMed] [Google Scholar]
- KATZ B., MILEDI R. THE EFFECT OF CALCIUM ON ACETYLCHOLINE RELEASE FROM MOTOR NERVE TERMINALS. Proc R Soc Lond B Biol Sci. 1965 Feb 16;161:496–503. doi: 10.1098/rspb.1965.0017. [DOI] [PubMed] [Google Scholar]
- Kopin I. J. Biochemical aspects of release of norepinephrine and other amines from sympathetic nerve endings. Pharmacol Rev. 1966 Mar;18(1):513–523. [PubMed] [Google Scholar]
- Miledi R., Slater C. R. The action of calcium on neuronal synapses in the squid. J Physiol. 1966 May;184(2):473–498. doi: 10.1113/jphysiol.1966.sp007927. [DOI] [PMC free article] [PubMed] [Google Scholar]
- NASH C. W., COSTA E., BRODIE B. B. THE ACTIONS OF RESERPINE, GUANETHIDINE AND METARAMINOL ON CARDIAC CATECHOLAMINE STORES. Life Sci. 1964 May;3:441–449. doi: 10.1016/0024-3205(64)90204-8. [DOI] [PubMed] [Google Scholar]
- POTTER L. T., AXELROD J. SUBCELLULAR LOCALIZATION OF CATECHOLAMINES IN TISSUES OF THE RAT. J Pharmacol Exp Ther. 1963 Dec;142:291–298. [PubMed] [Google Scholar]
- Potter L. T. Storage of norepinephrine in sympathetic nerves. Pharmacol Rev. 1966 Mar;18(1):439–451. [PubMed] [Google Scholar]
- ROBERTS M. A note on the use of cellulose phosphate cation-exchange paper for the separation of catecholamines, and some other biogenic amines. J Pharm Pharmacol. 1962 Nov;14:746–749. doi: 10.1111/j.2042-7158.1962.tb11170.x. [DOI] [PubMed] [Google Scholar]
- ROSELL S., KOPIN I. J., AXELROD J. FATE OF H3-NORADRENALINE IN SKELETAL MUSCLE BEFORE AND FOLLOWING SYMPATHETIC STIMULATION. Am J Physiol. 1963 Aug;205:317–321. doi: 10.1152/ajplegacy.1963.205.2.317. [DOI] [PubMed] [Google Scholar]
- SHANES A. M. Electrochemical aspects of physiological and pharmacological action in excitable cells. I. The resting cell and its alteration by extrinsic factors. Pharmacol Rev. 1958 Mar;10(1):59–164. [PubMed] [Google Scholar]
- Titus E., Dengler H. J. The mechanism of uptake of norepinephrine. Pharmacol Rev. 1966 Mar;18(1):525–535. [PubMed] [Google Scholar]
