Histamine and serotonin released from the rat perfused heart by compound 48/80 or by allergen challenge influence noradrenaline or acetylcholine exocytotic release

摘要: Terminal nerve fibres of the autonomic nervous system closely approach mast cells in peripheral organs, and mutual influences between release neurotransmitters or cell mediators may cause neuro-immunological interactions. We have studied influence degranulation on endogenous noradrenaline newly incorporated acetylcholine (such as 14C-choline/acetylcholine overflow) evoked by stimulation extrinsic postganglionic sympathetic preganglionic vagal nerves rat Langendorff heart perfused with Tyrode solution. Compound 48/80 normal hearts, ovalbumin infused into hearts from rats sensitized to ovalbumin, enhanced overflow histamine serotonin. Both stimuli increased a similar extent fast kinetics. Maximum average concentrations perfusate were about 800 nmol/l, serotonin 40 sample collected within 4 min after degranulation. Stimulation did not affect basal overflow. Whereas overflows unaffected, stimulation-evoked releases both acetylcholine, facilitated when compound was before during stimulation. The facilitation more pronounced (by 60%) 48/80-induced mediator started compared 30 s (15%), reduced cocaine 50%), and, presence cocaine, abolished cimetidine (but unaffected mepyramine thioperamide) NG-nitro-(L)-(-)-arginine. In facilitatory components abolished, observed start infusion inhibited, inhibition partly methiotepin ketanserin. Ovalbumin animals caused an sensitive also ketanserin, no observed. (> 100%) at perfusion thioperamide cimetidine) comparable either tropisetron (3 mumol/l) alone plus methiotepin. conclusion, immunological is followed rather unusual ways, i) uptake1-dependent ii) H2-mediated which probably involves nitric oxide permissive mediator, iii) serotonergic inhibition, release, iv) H3- release.