International Journal of Marine Science 2016, Vol.6, No.4, 1-12
6
Figure 1
Cardiovascular defects induced in Tg (fil-1: EGFP) zebrafish at 2 dpf following exposure to 1
M of 4-t-OP. Lateral view
of (A, C and E) control Tg (fil-1: EGFP) zebrafish and (B, D and F) 1
M 4-t-OP treated Tg (fil-1: EGFP) embryos. (A, B, C and D)
Photos were acquired by merging bright field and dark field using FITC filter. (E and F) Photos were acquired form dark field using
FITC filter.
3.3 4-t-octylphenol damage cardiovascular function
The phenotypes of cardiovascular defect induced by
4-t-OP urge us to investigate the effect of 4-t-OP on
cardiovascular function. Heart rate variability is a
representative index for evaluating the function of
cardiovascular function. The development of the
cardiac circulation in zebrafish is completed by 48
hpf, so the heart rate was examined at 48, 72 and 96
hpf to evaluate the effects of 4-t-OP on cardiac
contraction. Although the heart rate of zebrafish at
48, 72 and 96 hpf were decreased than control group
following exposure to 4-t-OP at 0.5
M, there was
no significant statistical difference between control
and 4-t-OP treated group; however zebrafish
embryos exposed to 1
M of 4-t-OP significantly
reduced heart rate at 48, 72 and 96 hpf compared to
that in control group. The heart rate in 4-t-OP treated
zebrafish at 48, 72 and 96 hpf were decreased around
14.4%, 17.1% and 14.5% respectively compared to
control group (Fig. 2). Furthermore, zebrafish
exposed to 1
M of 4-t-OP resulted in a slower blood
flow rate or a blockage of blood flow was also
observed. These results elucidated that exposure to
4-t-OP had potentially damage to cardiovascular
function.
