Autoradiograms regarding steroid metabolites away from vitellogenic ovarian follicles of the bambooleaf wrasse incubated which have [7- step three H]pregnenolone

Autoradiograms regarding steroid metabolites away from vitellogenic ovarian follicles of the bambooleaf wrasse incubated which have [7- step three H]pregnenolone

Eight metabolites had been broke up of the thin covering chromatography and you can developed with benzene:acetone (4:1). step one, E1; dos, AD; step three, P5; 4, DHEA 17-P; 5, E2; 6, 1seven-P5; 7, 17,20?-P 17,21-P; and you can 8, 17,20?-P5. Pick Table step one for steroid abbreviations.

Table 3

To search for the steroidogenic path from E2 synthesis, five most other radiolabeled steroid drugs were used since the precursors for for the vitro incubation of follicles. Ones four precursors, E2 is actually synthesized off [ fourteen C]DHEA, [ fourteen C]Offer, and you may [ step three H]E1. Whenever hair follicles was indeed incubated which have [ step three H]17-P, E2 was not thought as the metabolite, and you can a little bit of Post was delivered. In most incubations, T production cannot be thought of, and you can [ fourteen C]T wasn’t entirely changed into E2.

Aspect off serum steroid account

Solution quantities of E2 and you may E1 presented similar pages inside the an effective day of spawning 12 months (Fig. 2). At hour, in the event the developmental phase of one’s biggest oocytes was LMN, serum E2 and you can E1 accounts was in fact significantly large (E2= ng/ml, E1= 5.08 ng/ml). However, of the time, in the event the stage of the prominent oocytes are Meters, the amount fell (E2=5.03 ng/ml, Estep 1=step one.fifty ng/ml) and you can remained lingering profile at the and you will hr, if amount of one’s premier oocytes was in fact TY and you will EMN, respectively (E2=six.00 ?6.twenty-seven ng/ml, E1=1.15–step one.79 ng/ml). Yet not, T and Ad account was in fact constant (T=step 1.22–step one.71 ng/ml, AD=step one.23–step 1.43 ng/ml) all day long and didn’t differ notably one of ovarian amount (Fig. 3).

Fig. 2

Changes in the serum levels of estradiol-17? (E2) and estrone (E1) in female bambooleaf wrasse sampled at different times of a day during the spawning season. Numbers indicate sample size. Each value is the mean±SEM. Statistically significant differences between groups are shown by different letters (P<0.05).

Fig. 3

Changes in serum degrees of testosterone (T) and androstenedione (AD) in ladies bambooleaf wrasse tested at the different times regarding day from inside the spawning year. Quantity suggest decide to try dimensions. For every worth ‘s the suggest±SEM.


This study reveals the latest steroidogenic pathway so you’re able to E2 synthesis about ovarian follicles off bambooleaf wrasse (Fig. cuatro, vitellogenic pathway). Over the last 20 years, a good amount of knowledge towards the steroidogenesis throughout vitellogenesis, in different teleosts, keeps incubated intact ovarian hair follicles otherwise fragments or mentioned bloodstream steroid levels. when you look at the vitro incubation away from ovarian follicles (amago salmon Oncorhynchus rhodurus , Kagawa et al., 1982; goldfish, Kagawa ainsi que al., 1984; guppy Poecilia reticulata , Venkatesh mais aussi al., 1992; medaka Oryzias latipes, Kobayashi mais aussi al., 1996) otherwise ovarian fragments (e.grams., Atlantic croaker Micropogonias undulatus , Trant and you will Thomas, 1989) demonstrated one to E2 was synthesized thru T. In numerous varieties, it has been found you to bloodstream E2 levels improve during vitellogenesis, along with T accounts (e.grams., plaice Pleuronectes platessa , Wingfield and you can Grimm, 1977; light sucker Catostomus commersori , Scott et al., 1984; spotted seatrout Cynoscion nebulosus , Thomas et al., 1987; yellow seabream Pagrus significant, Matsuyama ainsi que al., 1988; gulf killifish Fundulus grandis , Greeley et al., 1988; sea trout Dicentrarchus labrax , Prat ainsi que al., 1990; demoiselles Chromis dispilus , Barnett and you may Pankhurst, 1994; striped bass Morone saxatilis , Queen et al., 1994; spiny damselfish Acanthochromis polyacanthus , Pankhurst mais aussi al., 1999). This research provides provided us to the approved examine that T is a precursor having E2 design about teleost ovary. Within analysis, yet not, T was not created by vitellogenic hair follicles just after incubation which have radiolabeled precursors, and you may exogenous T wasn’t converted to E2 in the follicles. Such abilities obviously mean that during the bambooleaf wrasse T isn’t the latest forerunner having E2 manufacturing about vitellogenic follicles. On the other hand, E1 try introduced instead of T off P5, DHEA, and you can Ad, and you can exogenous E1 is actually converted directly into E2. The results recommend that E2 is actually synthesized regarding E1 throughout the vitellogenic follicles. More over, the solution steroid levels, in which serum E2 levels presented a great diurnal flow you to definitely paralleled E1 membership although not T levels, support the in vitro study. To our education, this is the first report that E1 ‘s the biggest sandwich-stratum out-of E2 regarding the ovarian follicles from inside the an effective teleost.

About the Author