Nnwale Ames maka N-Nitrosamines: Nyochaa Mutagenicity

Okwu Mmalite na Ames Test

Nnwale Ames, nke a makwaara dị ka Bacterial Reverse Mutation Test bụ ihe a na-ejikarị eme ihe maka nyocha nke ndu nke na-enyocha ikike mutagenic nke ogige kemịkal, gụnyere N-Nitrosamines. Dr. Bruce Ames mebere na 1970s, ule a na-eji ụdị nje bacteria Salmonella typhimurium nke na-ebu mmụgharị nke mkpụrụ ndụ ihe nketa na-etinye aka na njikọ nke histidine. Nnwale a na-ekpebi ma ihe nwere ike ibute mmụgharị na DNA nje bacteria, na-enye ihe ngosi nke nwere ike ibute ọrịa carcinogenic na mmadụ.

Mkpa nke Ames Test maka N-Nitrosamines

N - Nitrosamines mara maka ihe ha nwere genotoxic na carcinogenic, ebe ha nwere ike imebi DNA site na alkylation na nrụgide oxidative. Nnwale Ames bara uru karịsịa n'ịchọpụta mmetụta mutagenic ha, n'ihi na ọtụtụ N - Nitrosamines chọrọ ka arụ ọrụ metabolic site na ntụgharị enzymatic ka ọ na-etolite etiti electrophilic na-arụ ọrụ nke ọma nwere ike ịmekọrịta DNA. Nke a na-arụ ọrụ na-emekarị na imeju site na cytochrome P450 enzymes. Iji megharịa ntụgharị nke metabolic a na vitro, a na-eme nnwale ahụ na-enweghị mgbakwasa metabolic site na iji S9 mix, nkwadebe enzyme imeju nke sitere na òké, nke na-eṅomi metabolism mammalian ma na-eme ka nchọpụta nke ọrụ mutagenic dịkwuo elu.

Usoro nke Ames Test

Usoro ọkọlọtọ nke ule Ames gụnyere usoro ndị a:

1. 1. Nkwadebe nke Ule Ule: Ụdị Salmonella typhimurium nwere ngbanwe dị adị na mkpụrụ ndụ ihe nketa histidine. Ụdi ndị a enweghị ike itolite ma ọ bụrụ na enweghị isi iyi histidine dị n'èzí, ọ gwụla ma mmụgharị azụ na-eweghachi ọrụ.
2. 2. Ngosipụta na N - Nitrosamines: A na-ejikọta omenala nje bacteria na ihe nyocha (N-Nitrosamine) na obere efere agar nwere obere histidine.
3. 3. Metabolic Activation (S9 Mix Addition): Iji nweta akaụntụ maka mgbanwe metabolic na ahụ mmadụ, ụfọdụ ihe nlele ule na-agụnye akụkụ S9, ihe ntinye enzymatic sitere na microsomes imeju oke.
4. 4. Mmụba na Uto: A na-etinye efere ndị ahụ na 37 ° C maka awa 48, na-ekwe ka mpaghara nje bacteria na-eto eto ma ọ bụrụ na mmụkọ emee nke na-eweghachi njikọ histidine.
5. 5. Ngụkọta Colony na Nyocha: A na-agụta ọnụ ọgụgụ nke ndị na-alọghachi azụ (bacteria nke nwetaghachiri ikike imepụta histidine) ma jiri ya tụnyere efere nchịkwa.
6. Nkọwa nke nsonaazụ

• Nnwale Ames dị mma: Mmụba dị ịrịba ama na mpaghara ndị na-alọghachi azụ ma e jiri ya tụnyere njikwa ahụ na-egosi na ogige ahụ na-ebute mmụgharị, na-egosi ihe mutagenic na nwere ike ịkpata ọrịa carcinogenic.
• Nnwale Ames na-adịghị mma: Ọ bụrụ na ahụghị mmụba dị ịrịba ama, ogige ahụ nwere ike ọ bụghị - mutagenic n'okpuru ọnọdụ ule.
• Dose - Mmekọahụ nzaghachi: Ngwọta dị elu na-eduga n'ịba ụba mmụgharị na-ewusi ihe akaebe nke mutagenicity ike.

Mmechi

Nnwale Ames bụ ngwa ngwa na ọnụ ahịa-ụzọ dị irè maka ịlele mutagenicity nke N-Nitrosamines. N'inye njikọ ha na ọrịa kansa, ịchọpụta njirimara mutagenic ha site na nyocha a dị oke mkpa maka njikwa nhazi na nyocha ihe egwu. Nnwale a ka bụ isi nkuku na nyocha toxicological na nyocha nchekwa kemịkal.

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