The serotonin agonist, M-chlorophenylpiperazine, markedly increases levels of plasma catecholamines in the conscious rat.
Intravenous administration of the serotonin agonist, m-chlorophenylpiperazine (m-CPP), produced large, dose-dependent increases in epinephrine, norepinephrine and dopamine in plasma in normal, conscious rats. Elevations in the levels of epinephrine, norepinephrine and dopamine (10-fold, 5-fold and 2-fold, respectively) were markedly reduced in pithed and splanchnic denervated rats, suggesting that CNS mechanisms are primarily responsible for the effect of m-CPP on catecholamines in plasma. The serotonin antagonist, metergoline (0.5 mg/kg), decreased the responses of epinephrine and dopamine to m-CPP by 60-80% and also tended to decrease the response of norepinephrine. These findings are consistent with other studies reporting that stimulation of serotonergic receptors increases centrally-mediated sympathetic outflow and leads to increases in the concentrations of norepinephrine, epinephrine and dopamine in plasma.
Bagdy
G
G
Laboratory of Clinical Science, National Institute of Mental Health, Bethesda, Maryland 20892.
Szemeredi
K
K
Hill
J L
JL
Murphy
D L
DL
D000818:Animals; D002395:Catecholamines / Q000097:blood*; D003655:Decerebrate State; D003714:Denervation; D004298:Dopamine / Q000097:blood; D004837:Epinephrine / Q000097:blood; D008297:Male; D008711:Metergoline / Q000494:pharmacology; D009638:Norepinephrine / Q000097:blood; D010879:Piperazines / Q000494:pharmacology*; D051381:Rats; D011919:Rats, Inbred Strains; D011985:Receptors, Serotonin / Q000187:drug effects*; D013153:Splanchnic Nerves / Q000502:physiology*
D002395:Catecholamines; D010879:Piperazines; D011985:Receptors, Serotonin; D008711:Metergoline; C015068:1-(3-chlorophenyl)piperazine; D004298:Dopamine; D009638:Norepinephrine; D004837:Epinephrine