Environmental and Molecular Mutagenesis - Legacy Tobacco ...

88 1989 EMS Abstracts 250
http://legacy.library.ucsf.edu/tid/clb93d00/pdf
Notes EFFECTS OF PROGFSTERONE AND ESTRADIOL ON PROLIFFRATION OF HUMAN L1'MPFDCYTFS IN VITRO .
L .A . Herrera M ., R . Montero M ., and P . Ostrosky-Wegman . Instituto de InvestTgacones
Biom6dicas, UNAM, Apdo . Postal 70228, 14sxico 04510 D .F . Mexico .
During a study of lymphocyte cell-cycle kinetics we found variability between individuals
and between samples of the same individual taken at different times . Trying to
understand some of the factors that could be involved in those variations, we thought
over the relationship between menstrual cycle and cell vroliferation . In vivo studies
on blood from 6 women, sampled every week during 3 months, didn't show any cTar effect
that could be directly correlated with their menstrual cycles . Since many other factors
could be interfering in our studies, we evaluated in vitro effects of estradiol
and progesterone over cell proliferation kinetics (CPK) ard'Ft'totic Index (MI) on
human lymphocytes both from men and from women on day 1 of menstrual cycle (lowest
concentrations of respective hormones) . The two hormones were added to the cultures
individually or simultaneously, 2 h after stimulation with PHA . Lowest doses of each
hormone showed an inhibitory effect on CPK and MI . When the hormones were added
simultaneously, the t of cells in 3th or more divisions decreased at doses similar to
those found in menstrual and lutheal phases, whereas it increased at doses similar to
the ovulatory phase . The MI of lymphocytes from women donors decreased at all doses
of the hormones, whereas those of men donors decreased only at doses similar to menstrual
phase . The effects of hormones on lymphocyte cell cycle should be further
studied mainly in relation to the recently described increased sensitivity to genotoxic
dama?e on lymphocytes from both pregnant women and women taking oral hormonal
contraceptives, and to the well known increased sensitivity to infections of pregnant
women .
PROTOCOL EVALUATION FOR THE MICRONUCLEUS TEST . C . Hilliard, R . Tice, and M.D .
Shelby*, Integrated Laboratory Systems, P0 Box 13501, Research Triangle Park, NC
27709 and *NIEHS . P0 Box 12233, Research Triangle Park, NC 27709 .
251
Using dimethylbenzanthracene (DNBA) and benzidine (B2D), the efficacy of three
different in vivo micronuclei (MN) protocols were evaluated, using polychromatic
erythrocytes (PCE) sampled In both bone marrow and peripheral blood . B6C3F1 male
mice (9-12 weeks of age ; 5 mice per group) were Injected IP with DMBA (25, 50, 100
mg/kg) or with BZD (50 . 100, 200, 300 mg/kg) on 1, 2, or 3 consecutive days, with
bone marrow and peripheral blood smears being made at 24, 48, and/or 72 hours after
the first injection . Slides were stained with acridine orange and 2000 PCE scored
per tissue per animal for the presence of MN . DMBA induced a significant increase in
MN-PCE at all sample times in both tissues using all three protocols, with the yield
of MN-PCE at 48 and 72 hr being independent of treatment protocol and tissue . BZD
induced a positive response in bone marrow and peripheral blood only when injected 2
or 3 times and sampled at 72 hr after the first injection . When administered by
gavage, a significant increase in MN-PCE was induced by BZD in bone marrow 24 hr
after a single treatment, with increased activity being demonstrated after 3 daily
injections . These data indicate that a treatment protocol based on multiple
injections eliminates the need for multiple sampling times, minimizes the number of
animals and scoring time, and simplifies the statistical analysis . Also, the lack of
a significant difference in MN levels between bone marrow and peripheral blood
suggest that either tissue can be used following this protocol . Supported by NTP
contract N01-ES-85209 .
252
RELATIONSHIPS BETWEEN STRUCTURE OF NITRATED ARENES AND THEIR MUTAGENICITY IN SALMONEL-
LA TYPHIMURIUH ; 2- AND 2,7-NITRO SUBSTITUTED FLUORENE, PHENANTHRENE AND PYRENE
T. Nirayama, T . Watanabe, Y . Fujioka, S . Ozasa, and S . Pukui, Kyoto Pharmaceutical
University, Kyoto (Japan)
In order to elucidate the mechanisms of autagenic activation of nitroarenes, we
studied the relationships between the autagenic potency and chemical structure of 2nitro-
and 2,7-dinitro-arenes including nitrated fluorene (F1), dihydrophenanthrene
(DNPh), phenanthrene (Ph), tetrahydropyrene (TBPy), dihydropyrene (DHPy) and pyrene
(Py) together with 9-N02-Ph, 1-N02-Py and 1,3-diN02-Py . The autagenicity tests were
carried out on Salmonella typhimurium TA98, TA98NR and TA98/1,8-DNP6 in the absence of
S9 mix . The order of mutability of mononitro- and dinitro-arenes in TA98 is as given
below : 2-NOy-THPy