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: Accumulation of 3H-(-)noradrenaline in the rabbit aorta not related to uptake1 and uptake2, but sensitive to 3,4-dihydroxy-2-methylpropiophenone (U-0521) and oxytetracycline.
    Author: Henseling M.
    Journal: Naunyn Schmiedebergs Arch Pharmacol; 1983 Jun; 323(2):121-7. PubMed ID: 6888566.
    Abstract:
    1. Some of the extraneuronal accumulation of 3H-(-)noradrenaline in the rabbit aorta was resistant to uptake2 inhibitors (corticosterone, normetanephrine, phenoxybenzamine). Even combined treatment of the tissue with the competitive inhibitor corticosterone (87 mumol . l-1) and the irreversible inhibitor phenoxybenzamine (90 mumol . l-1) was not more effective than was corticosterone alone. 2. The corticosterone-resistant extraneuronal accumulation of 3H-(-)noradrenaline (0.12 mumol . l-1) was reduced by about 30% by the COMT inhibitor U-0521 (1000 mumol . l-1) and by oxytetracycline (100 mumol . l-1). Combined treatment with U-0521 and oxytetracycline was not more effective than was U-0521 alone. Already 1 mumol . l-1 U-0521 had a half-maximal effect, i.e., it reduced accumulation by 15%. This effect of U-0521 was not related to its known ability to block uptake2. The catechol U-0521 probably inhibited binding of noradrenaline to a catechol-specific site. Furthermore, the accumulation was sensitive to the two iron-chelating agents deferoxamine and phenanthroline but not to ascorbic acid and N-ethylmaleimide. 3. A relatively high formation of 3,4-dihydroxymandelic acid (DOMA) took place in the corticosterone-resistant extraneuronal compartment of the mechanically denervated aorta. This formation of DOMA was probably a consequence of tissue injury brought about by removing the adventitia.
    [Abstract] [Full Text] [Related] [New Search]