Abstract
Effects on chromosomes were studied in human lymphocytes in vitro as a result of treatment
by coumarin derivatives in the dark. This paper presents investigations with the linear
furocoumarins 8-methoxypsoralen (8-MOP; xanthotoxin) and 8-isoamylenoxypsoralen (8-IOP;
imperatorin), the angular furocoumarin 5′-methylangelicin (5′-MA), and, in addition,
the simple coumarin 5,7-dimethoxycoumarin (5,7-DMC).
8-MOP and 8-IOP influenced the growth of lymphocytes basically in the same way, different
from that of the angular derivative; 5,7-DMC had no effect compared to the control.
We found a slight but reproducible increase in sister chromatid exchange (SCE) frequency
equivalent to 3,7 induced SCE/metaphase with 8-MOP in the dark. 5′-MA and 8-IOP had
no significant effect on SCE frequency under these conditions. 5,7-DMC resulted in
1,9 induced SCE/metaphase. 8-MOP also revealed a slight clastogenic activity as 8-IOP
does. The chromosome damaging effect was expressed mainly in a doubling of the break
rate.
Relations between structure and activity of the tested compounds as between both types
of cytogenetic effects, SCE and chromosome aberrations, are discussed.
Key Word Index
Coumarins - Psoralens - Angelicins - Sister Chromatid Exchange
