GB 15193.13-2015 National food safety standard Mice spermatogonium or spermatocyte chromosome aberration test
1 Scope
This standard specifies the basic test methods and technical requirements for mice spermatogonium or spermatocyte chromosome aberration test.
This standard is applicable to evaluate the mice germ cell chromosome damage caused by the test substance, with spermatogonia or spermatocytes selected as target cells according to specific conditions.
2 Terms and definitions
2.1
spermatogonium
stem cells in the epithelium of the male mammalian seminiferous tubules which can proliferate through multiple mitosis and undergo meiosis to produce spermatocyte, and which are the primitive male germ cells and have the same number of chromosomes as somatic cells
2.2
spermatocyte
cells produced by spermatogonia through meiosis that can eventually differentiate into mature sperm, which are divided into primary spermatocytes and secondary spermatocytes, with the number of chromosomes in secondary spermatocytes halved to 1n
2.3
chromosome structure aberration
structural change in a chromosome that can be directly observed through a microscope at mid-cell mitosis, which can be categorized into chromosome-type aberrations and chromatid-type aberrations
2.4
chromosome-type aberration
chromosome structure damage, which is characterized by breakage or reconnection of two chromatids at the same site
2.5
chromatid-type aberration
chromosome structure damage, which is characterized by breakage or reconnection of chromatid
2.6
chromosome number aberration
chromosome number changes, which is different from normal diploid karyotype, including euploid and aneuploid
3 Test objective and principle
The test samples were given orally to the laboratory animals and the animals were executed after a certain period of time. The chromosome aberration of spermatogonia or spermatocyte of testis was observed to evaluate the mutagenicity of the test samples to male germ cells.
Before the animals were executed, they were treated with mid-cytokinesis blockers, and both testes were taken out after being executed, and spermatogonia or spermatocyte chromosome specimens were prepared after hypotonicity, fixation, softening and staining, and the mid-cytokinesis-phase cells were observed under the microscope to analyze the chromosome aberrations of spermatogonia or spermatocytes.
4 Apparatus and reagents
4.1 Common laboratory apparatus
Anatomical instruments, electronic balance, refrigerators, centrifuges and so on commonly used in laboratory.
4.2 Reagents
4.2.1 0.1% colchicine
Store it in a brown bottle and keep it in a refrigerator.
4.2.2 1% trisodium citrate
Take 1g of trisodium citrate (analytically pure) and add distilled water to 100mL.
Foreword i
1 Scope
2 Terms and definitions
3 Test objective and principle
4 Apparatus and reagents
5 Test methods
6 Data processing and results evaluation
7 Test report
