Biology Reference
In-Depth Information
a)
12
LH
FSH
Alpha
10
8
6
4
2
0
A
B
C
D
E
Silver
Yellow
Intermediate
Eel stage
b)
1000
E2
T
11-KT
750
500
250
0
Yellow
Silver
Intermediate
Eel stage
Figure 4
. Involvement of gonadotropic axis in the control of eel silvering. During the process
of silvering, there is an activation of gonadotropic axis as pituitary gonadotropin (LH β
and FSH β) mRNA levels (a) and plasma sex steroids (E2, T and 11-KT) levels increase.
LH=luteinizing hormone; FSH=follicle-stimulating hormone; E2=estradiol; T=testosterone;
11KT=11-ketotestosterone; alpha=GP alpha.
slight decrease in FSH, suggests that LH may participate in the induction of
Vg production and initiation of the “exogenous vitellogenesis”. Similarly,
LH may also participate in the second increase in sex steroid levels, in
silver eels.
In summary, among the different pituitary hormones that were studied,
the gonadotropins, LH and FSH, showed the biggest variations during eel
silvering.
