These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: The effects of putative 5-hydroxytryptamine antagonists on the behaviour produced by administration of tranylcypromine and L-tryptophan or tranylcypromine and L-DOPA to rats.
    Author: Deakin JF, Green AR.
    Journal: Br J Pharmacol; 1978 Oct; 64(2):201-9. PubMed ID: 708990.
    Abstract:
    1 The putative 5-hydroxytryptamine (5-HT) receptor blocking drugs methysergide (10 mg/kg) and methergoline (5 mg/kg) were found to abolish some components of the hyperactivity syndrome, including head weaving and forepaw treading, which follow administration to rats of tranylcypromine (20 mg/kg) and L-tryptophan (100 mg/kg). Hyperactivity and hyper-reactivity were potentiated with a resultant increase in automated locomotor activity counts. In contrast (-)-propranolol (20 mg/kg) inhibited all features of the syndrome. The same results were obtained with these drugs when the behaviour was elicited by p-chloroamphetamine (10 mg/kg) or by tranylcypromine and tryptamine (10 mg/kg). 2 Methysergide and methergoline had similar effects on the syndrome produced by tranylcypromine and L-DOPA (50 mg/kg) whereas propranolol was without effect. 3 None of the putative 5-HT receptor antagonists affected brain 5-HT turnover as assessed by rate of accumulation of 5-HT following monoamine oxidase inhibition with tranylcypromine. 4 Microinjections of 5,7-dihydroxytryptamine into the spinal cord resulted in a 70% fall in cord 5-HT concentrations without an effect on brain 5-HT concentrations. The behavioural response to the putative 5-HT receptor agonist, 5-methoxy N,N-dimethyltryptamine (2 mg/kg), was potentiated in these animals suggesting that 5-HT receptors become supersensitive on denervation, and that some components of the behavioural syndrome are mediated by spinal cord 5-HT receptors. 5 Pretreatment with alpha-methyl p-tyrosine (2 X 200 mg/kg) delayed the onset of all components of the behaviour elicited by tranylcypromine/L-tryptophan by 60 min, indicating an involvement of catecholamines in the syndrome. 6 p-Chloroamphetamine-induced 5-HT depletion had no effect on any component of the tranylcypromine-L-DOPA behaviour.
    [Abstract] [Full Text] [Related] [New Search]