P2 purinoceptors modulating noradrenaline release from sympathetic neurons in culture.
ATP (1 mM) inhibited, whereas 2-methylthio-ATP (30 microM), a P2Y-selective purinoceptor agonist, increased electrically evoked release of [3H]noradrenaline from chick sympathetic neurons. The P2X-selective purinoceptor agonist alpha,beta-methylene-ATP (30 microM) had no effect. The ATP-induced inhibition of release as well as the facilitation caused by 2-methylthio-ATP was not affected by the selective adenosine (P1) receptor antagonist 8-(p-sulfophenyl)-theophylline (8-PST; 100 microM), but completely prevented by the non-selective P2 antagonist suramin (300 microM). The present data reveal a dual regulation of noradrenaline release from sympathetic neurons. Facilitation seems to be mediated by a P2Y purinoceptor, whereas inhibition is caused by a P2 purinoceptor which needs further subtype characterization.
Allgaier
C
C
Institute of Pharmacology and Toxicology, Albert-Ludwigs University of Freiburg, Germany.
Pullmann
F
F
Schobert
A
A
Von Kügelgen
I
I
Hertting
G
G
D000255:Adenosine Triphosphate / Q000031:analogs & derivatives / Q000494:pharmacology; D000818:Animals; D002478:Cells, Cultured; D002642:Chick Embryo; D004558:Electric Stimulation; D005728:Ganglia, Sympathetic / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D009474:Neurons / Q000187:drug effects / Q000378:metabolism*; D009638:Norepinephrine / Q000378:metabolism*; D018341:Receptors, Adrenergic, alpha-2 / Q000187:drug effects / Q000378:metabolism; D018048:Receptors, Purinergic P2 / Q000187:drug effects / Q000502:physiology*; D013564:Sympathetic Nervous System / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D013806:Theophylline / Q000031:analogs & derivatives / Q000494:pharmacology; D013873:Thionucleotides / Q000494:pharmacology
D018341:Receptors, Adrenergic, alpha-2; D018048:Receptors, Purinergic P2; D013873:Thionucleotides; C031433:8-(4-sulfophenyl)theophylline; D000255:Adenosine Triphosphate; D013806:Theophylline; C002630:alpha,beta-methyleneadenosine 5'-triphosphate; D009638:Norepinephrine; C008501:2-methylthio-ATP