第四章內(nèi)源性動(dòng)物毒物32555

NaturaltoxinsinconsumptionBacterialtoxinsPhycotoxins(marinealgae,shellfishFishpoisons(tetrodotoxin河豚毒素scombrotoxins鯖魚(yú)Otheranimalpoisons(livers,birds,Bacterialtoxins:ClostridiumbotulinumcausesMechanism:botulininhibitsreleaseofacetylcholinebypresynapticmembrane（突觸前膜）ofmotorendplates（運(yùn)動(dòng)終板）andblocksthecalciumchannelBacterialtoxins:LD50=0.0001Lethaldose:inhalation0.3μg,oralingestion8-10Phycotoxins(shellfishFromdinoflagellates甲藻:accumulateinthefoodchaininparticularinshellfishduringredtidesFromalgaetoPhycotoxins(shellfishparalyticshellfishpoison(PSP)–(Alexandriumspsaxitoxin(亞歷山大藻)diarrheticshellfishpoison(DSP)–(Dinophysissp.)okadaicacid(鰭藻)neurotoxicshellfishpoison(NSP)–amnesicshellfishpoison(ASP)–(Pseudo-nitzschiasp.)domoicacid(擬菱形藻ciguaterafishpoison(CFP)–(Gambierdiscussp.)ciguatoxin(甲藻)Phycotoxins:paralyticshellfishpoison(PSP)nausea,vomiting,coordinationrespirationparalysis(from1Phycotoxins:paralyticshellfishpoison(PSP)nausea,paralysisPhycotoxins:neurotoxicshellfishpoison(NSP)Mechanism:enhancementNa-EffectscomparabletoPSP,butnoPhycotoxins:gastrointestinal,neurological,andcardiovascularsymptomsCaribbeanfoodMechanism:enhancementNa-Phycotoxins:sodiumPhycotoxins:diarrheticshellfishpoison(DSP)inhibitorsofser/thrproteinGIAccumulatesinFoodchain–Hyperphosphorylationofproteins,includingionchannels,intheintestinalepithelia,resultinimpairedwaterbalanceandlossofOkadaicPhycotoxins:Amnesicshellfishpoison(ASP)Overstimulationglutamateneurons:effecton Memoryloss–PrinceEdwardisland,Canada(1987)100peopleill,3DomoicNeurotoxicityduetotoxiclevelsofintracellularcalcium,whichleadstoneuronalcelldeathandlesionsinareasofthebrainwhereglutaminergicpathwaysareheavilyconcentrated.TheCA1andCA3regionsofthehippocampus(海馬體anarearesponsibleforlearningandmemoryprocessing,areparticularlysusceptibleFishpoisons:pufferNeurotoxin:tetrodotoxinblockingNachannelsInorgans:intestineovaria卵巢LD50:8-10paralysisbegins10-45minutesafteringestion,fixeddilatedpupilsdeathcanoccurwithin6-24Fishpoisons:pufferfish-Fishpoisons:scombroidBacterialcontaminatedhistidine-richTuna?Mackerel鮫Bonito鰹BiogenicLowmolecularweightorganicbases,whichposebiologicalactivity.Naturallypresentinanimals,plantsandSources:fermentedfoods,vegetables,Mainlycausedbytheenzymaticdecarboxylationofaminoacidsbymicroorganismorigin.HighconcentrationinfishandBiogenicJansenn,Put&NoutBiogenicBiogenicBiogenicFactorsinfluencingtheformationofbiogenicAmine-producingbacteria-(enterococci,lactobacilli,enterobacteriaceae,pediococci)TheavailabilityoffreeaminoThelevelofstartercultureBiogenicLegalupperlimit(Silla-Santos,histamine:100mg/kgtyramine:100-800mg/kgphenyletylamine:30mg/kg1000mg/kgamine(basedonhistamineint