组胺H_3受体介导抑制豚鼠心交感神经释放去甲肾上腺素的直接依据

Direct evidence for histamine H 3 receptor mediated inhibition of norepinephrine release from sympathetic terminals of guinea pig myocardium

组胺Ｈ３受体介导抑制豚鼠心交感神经释放去甲肾上腺素的直接依据罗晓星，文爱东１，郭治安２，谭月华（第四军医大学药理教研室，１西京医院临床药理室；２西北大学化学系，西安７１００３２，中国）关键词心房；电刺激；甲基组胺；组胺拮抗剂；去甲肾上腺素；节后交感神...

IM: To study the histamine H 3 receptors mediated inhibition of norepinephrine (NE) release from cardiac sympathetic terminals of guinea pig isolated atria. METHODS: Release of NE induced by electric field stimulation (50 mA, 5 ms) in the bath solution was measured by HPLC ECD. RESULTS: The release of NE caused by field stimulation was attenuated by (R) α methyl￣histamine (α MeHA, 0 1 nmol·L -1 -10 μ mol ·L -1 ) in a concentration dependent manner. Thioper￣ amide concentration dependently antago￣nized the inhibition of α MeHA. Blockade of H 1, H 2, α 2, β 2 receptors failed to prevent the inhibitory effect of α MeHA. Thioperamide (1 nmol·L -1 -10 μmol·L -1 ), when used alone, concentration dependently facilitated the release of NE evoked by field stimulation. CONCLUSION: The presynaptic histamine H 3 receptors inhibited the NE release from cardiac sympathetic terminals.