Mutagenic responses of nickel chloride in somatic and germ cells of mice invitro and invivo studies

ABSTRACT

The mutagenic response of Nickel chloride [Nicl[2][was evaluated in mice in vitro, in cultured mouse spleen cells. The cytotoxic effect of NiCl[2] was tested, the cultures were treated with the concentrations 10[-3]- 10[-6] M NiCl[2] /ml medium for 24 h The highest percentage of viable cells reached 88.79% in cultures treated with 10[-6] M NiCl[2]/ml medium compared with 92.5% in non-treated cell cultures. NiCl[2] at concentrations 10[-3]-10[-6] M/ml medium induced a significant percentage of chromosomal aberrations. It reached 8.75 +/- 0.65 [P< 0.01] in the cultures treated with 10[-3] M NiCl[2]/ ml medium, after excluding gaps versus 3.25 +/- 0.14 in the non-treated cell cultures. In vivo, single oral treatment by gavage at the doses 5, 25, 50, 75 mg NiCl[2] kg[-1] b. wt. induced an increase in the percentage of chromosomal aberrations in a dose dependent relationship. It's percentage at 75 mg kg[-1] b. wt was 12.2 +/- 1.16[without gaps] in bonemarrow and 10.6 +/- 0.60 [P < 0.01] in spermatocyte cells from that compared with 2.8 +/- .37 and 3.8 +/- 00.37 respectively in non-treated mice [background level]. Repeated treatment with the dose 5 mg NiCl[2] kg[-1] b. wt for 7, 14, 21 and 28 days did not induce a clear increase in the percentage of chromosomal aberrations than the single treatment It reached 8.2 +/- 0.80 [P< 0.05] in bone-marrow cells and 9.0 +/- 0.45 [P < 0.01] in spermatocyte cells after treatment with the dose 5 x 28 [140 mg Nicl[2] kg[-1] b. wt.] The same doses were used to study the morphological sperm- shape abnormalities. The two higher doses of NiCl[2] 50 and 75 mg kg[-1] b. wt induced a dase-dependant and statistically significant [P < 0.05] increase in the percentage of sperm-shape abnormalities. In conclusion, NiCl[2] has a weak mutagenic activity in mice, directly related to its ability to enter the cells. NiCl[2] produces genetic effect in vitro because its delivery and exposure can be controlled, but in vitro water - soluble NiCI[2] is rapidly removed from the body, therefore it induces a low percentage of chromosomal aberrations in somatic and germ cell