Ames Muedzo weN-Nitrosamines: Kuongorora Mutagenicity

Nhanganyaya kuAmes Test

Iyo Ames bvunzo, inozivikanwawo seBacterial Reverse Mutation Test inoshandiswa zvakanyanya pakuongorora zvipenyu inoongorora kugona kwemutagenic yemakemikari anosanganisira N-Nitrosamines. Yakagadzirwa naDr. Bruce Ames kumakore ekuma1970, bvunzo iyi inoshandisa mhando dzakanangana dzebhakitiriya reSalmonella typhimurium iro rinotakura kuchinja kwemajini anobatanidzwa mu histidine synthesis. Muedzo unoona kana chinhu chinogona kukonzera shanduko mubhakitiriya DNA, ichipa chiratidzo chezvingangoita carcinogenicity muvanhu.

Zvinoenderana neAmes Muedzo weN-Nitrosamines

N - Nitrosamines anozivikanwa nekuda kwegenotoxic uye carcinogenic zvimiro, sezvo achigona kukonzera kukuvara kweDNA kuburikidza nealkylation uye oxidative kusagadzikana. Muedzo weAmes unonyanya kubatsira pakuona mhedzisiro yavo, sezvo N - Nitrosamines zhinji inoda metabolic activation kuburikidza nekushandura enzymatic kuti iite yakanyanya reactive electrophilic intermediates inokwanisa kudyidzana neDNA. Iyi activation inowanzoitika muchiropa kuburikidza ne cytochrome P450 enzymes. Kudzokorora iyi metabolic shanduko mu vitro, bvunzo inowanzoitwa uye isina metabolic activation uchishandisa S9 musanganiswa, chiropa enzyme gadziriro inotorwa kubva kumakonzo, iyo inotevedzera mammalian metabolism uye inosimudzira kuonekwa kwe mutagenic chiitiko.

Nzira yeAmes Test

Iyo yakajairwa maitiro ebvunzo yeAmes inosanganisira anotevera matanho:

1. 1. Kugadzirira kweTest Strains: Salmonella typhimurium mashizha ane pre-aripo kuchinja mu histidine synthesis majini anoshandiswa. Aya madhiri haagone kukura pasina ekunze histidine sosi kunze kwekunge reverse mutation inodzoreredza basa.
2. 2. Kusangana neN - Nitrosamines: Chimiro chebhakitiriya chinosanganiswa nekomboni yekuedza (N - Nitrosamine) pane imwe agar plate ine shoma shoma ye histidine.
3. 3. Metabolic Activation (S9 Mix Addition): Kuzvidavirira kutendeuka kwemetabolism mumuviri wemunhu, mamwe masampuli ekuedza anosanganisira chikamu cheS9, an enzymatic extract kubva kumakonzo echiropa microsomes.
4. 4. Incubation uye Kukura: Mahwendefa akaiswa pa 37 ° C kwemaawa 48, zvichiita kuti mabhakitiriya awedzere kukura kana kuchinja kunoitika kunodzorera histidine synthesis.
5. 5. Colony Counting uye Analysis: Nhamba yemakoroni akadzoka (mabhakitiriya akawanazve kukwanisa kubudisa histidine) inoverengwa uye inofananidzwa nemahwendefa ekudzora.
6. Dudziro yeZvabuda

• Positive Ames Test: Kuwedzera kukuru kwemakoloni anodzokera kuenzaniswa nekutonga kunoratidza kuti komisheni inokonzera kuchinja, kureva mutagenic uye inogona kukonzera carcinogenic properties.
• Negative Ames Muedzo: Kana pasina kuwedzera kwakakosha kunoonekwa, iyo komputa inogona kunge isiri - mutagenic pasi pemamiriro ebvunzo.
• Dose - Response Relationship: Madosi epamusoro anotungamira mukuwedzera kushanduka kwemazinga anosimbisa humbowo hwe mutagenicity.

Mhedziso

Muedzo weAmes inzira inokurumidza uye inodhura-inoshanda yekuongorora mutagenicity yeN-Nitrosamines. Tichifunga nezvekushamwaridzana kwavo negomarara, kuziva kwavo mutagenic zvimiro kuburikidza neyeyedzo iyi kwakakosha pakudzora kudzora uye kuongorora njodzi. Muedzo uyu unoramba uri dombo repakona mukuongororwa kwetoxicological uye kuongororwa kwekuchengetedzwa kwemakemikari.

Keywords: N-Nitrosamines, NDSRIs, OECD 471, Enhanced Ames test, Hamster liver S9, Cytochrome P450 enzymes, Mutation Test