Adrenocortical steroid production by the interrenal tissue of the fresh-water European silver eel (Anguilla anguilla) and the marine eel (Conger conger) in vitro

1965 ◽  
Vol 16 (4) ◽  
pp. 583-588 ◽  
Author(s):  
D.G Butler
Keyword(s):  
Fresh Water ◽  
Anguilla Anguilla ◽  
Silver Eel ◽  
Steroid Production ◽  
Conger Conger

scholarly journals Effects of Benzo[a]pyrene, Cortisol, and 17ß-Estradiol on Liver Microsomal EROD Activity of Anguilla anguilla: An In Vitro Approach

2021 ◽  
Vol 11 (6) ◽  
pp. 2533
Author(s):  
C.S.S. Ferreira ◽  
Miguel Oliveira ◽  
Maria Ana Santos ◽  
Mário Pacheco
Keyword(s):  
Steroid Hormones ◽  
Scientific Information ◽  
Endocrine System ◽  
Anguilla Anguilla ◽  
Erod Activity ◽  
Biotransformation Process ◽  
Hepatic Microsomes ◽  
Polycyclic Aromatic ◽  
In Vitro Effects

Fish liver ethoxyresorufin-O-deethylase (EROD) activity is widely used as biomarker of exposure to chemicals such as polycyclic aromatic hydrocarbons (PAHs). It is known that endocrine system plays a major role in fish stress mechanism. Despite the considerable scientific information about steroid hormone’s response, namely cortisol and 17ß-estradiol (E2), to stress situations, little is known about the influence of these hormones on enzymes involved on the biotransformation process. Thus, this study aimed to assess the in vitro effects of environmentally relevant concentrations of benzo[a]pyrene (B[a]P) (0.1, 0.3, 0.9, and 2.7 µM) and of two steroid hormones (cortisol and 17ß-estradiol) in a physiologically relevant concentration (5.997 ng/mL), alone or in combination, on Anguilla anguilla liver microsomal EROD activity, previously induced by 4 mg/kg β-naphthoflavone intraperitoneal injection. Hepatic microsomes in vitro exposure to the tested B[a]P concentrations induced a dose response inhibition of EROD activity, whereas exposure to cortisol significantly induced the activity of this enzyme. The steroid hormones were able to decrease the inhibitory effects of B[a]P on microsomal EROD activity, thus revealing a protective effect of these hormones over enzyme activity inhibited by contaminants.

266 Effects of Inflammatory States on Ovarian Biology and Oocyte Competence

2021 ◽  
Vol 99 (Supplement_3) ◽  
pp. 134-135
Author(s):  
Jennifer A Hernandez Gifford ◽  
Emily Ferranti ◽  
Kylee Forrest ◽  
Craig A Gifford
Keyword(s):  
Granulosa Cell ◽  
Oocyte Maturation ◽  
Beta Catenin ◽  
Control Mechanisms ◽  
Steroid Production ◽  
Oocyte Competence ◽  
Nuclear Maturation ◽  
Naturally Occurring ◽  
Hormonal Milieu

Abstract Female fertility is dependent on estradiol concentrations which regulate a multitude of ovarian functions including follicle development and oocyte maturation leading to ovulation of a viable oocyte. Estradiol biosynthesis is regulated by coordinated actions of follicle-stimulating hormone and intra-ovarian control mechanisms including the co-transcription factor beta-catenin. Beta-catenin is a multi-faceted protein recognized for its role in granulosa cell steroid production and is shown to be modulated by lipopolysaccharide (LPS), the endotoxin responsible for stimulation of the immune system in infections caused by Gram-negative bacteria. Beef heifers treated with subacute concentrations of LPS during a synchronized follicular wave demonstrate a decline in serum estradiol concentrations 50 h after CIDR withdrawal, corresponding with dominant follicle maturation and preceding ovulation. The endotoxin exposure also resulted in increased LPS concentration and E2:P4 ratios in follicular fluid suggesting that low dose LPS modulates the intra-follicular hormonal milieu. Additionally, in a granulosa cell line, LPS treatment decreased mRNA expression of aromatase and beta-catenin. These data indicate that LPS alters E2 synthesis by modulating beta-catenin and subsequent steroidogenic enzyme expression. To further explore the contribution of naturally occurring LPS exposure on follicular steroid production and developing oocytes, bovine ovary pairs were collected from local abattoirs. Oocytes were aspirated from small follicles and matured in vitro to evaluate meiotic events related to nuclear maturation and spindle morphology. Small follicles from ovarian pairs were separated by the detectable LPS concentrations into high and low LPS groups. Oocytes matured from low LPS follicles demonstrated an increase in the percent of abnormal maturation events. Data indicate that induced or naturally occurring low doses of LPS can alter circulating and follicular estradiol concentrations impairing oocyte maturation. Perturbation to local ovarian signaling cascades from subclinical inflammatory disease may be an unappreciated factor altering fertility and leading to decreased cow retention.

scholarly journals Effet d'hormones gonadotropes, in vitro, sur la concentration de l'adénosine monophosphate cyclique dans l'ovaire de l'anguille (Anguilla anguilla L.)

1978 ◽  
Vol 18 (4) ◽  
pp. 805-811 ◽  
Author(s):  
Elizabeth FONTAINE-BERTRAND ◽  
C. SALMON ◽  
Y. A. FONTAINE ◽  
Nadine DELERUE-LE-BELLE ◽  
J. MARCHELIDON.
Keyword(s):  
Anguilla Anguilla

scholarly journals Lipid profiles of Mediterranean moray, Muraena helena, European conger, Conger conger, and European eel, Anguilla anguilla (Actinopterygii: Anguilliformes)

2017 ◽  
Vol 47 (1) ◽  
pp. 1-11
Author(s):  
Domagoj Điić ◽  
Irena Landeka ◽  
Radovan Fuchs ◽  
Daria Skaramuca ◽  
Sanja Matić-Skoko ◽  
...  
Keyword(s):  
Anguilla Anguilla ◽  
Lipid Profiles ◽  
European Eel ◽  
Conger Conger

scholarly journals Yield per recruit from stocking two different sizes of eel (Anguilla anguilla) in the brackish Roskilde Fjord

2015 ◽  
Vol 73 (1) ◽  
pp. 158-164 ◽  
Author(s):  
Michael I. Pedersen ◽  
Gorm H. Rasmussen
Keyword(s):  
Growth Rate ◽  
Scientific Information ◽  
Anguilla Anguilla ◽  
Silver Eel ◽  
Glass Eel ◽  
Recovery Plan ◽  
Yellow Eel ◽  
Roskilde Fjord ◽  
Yield Per Recruit ◽  
The Eu

Abstract Stocking of young eel is widely practised, as a measure, to meet the management target of the EU eel recovery plan. The target of the recovery plan is to increase the escapement to 40% silver eel biomass, relative to pristine conditions. The scientific information to predict the outcome in silver eel biomass from stocking is limited and may depend on whether translocation of wild glass eel or yellow eel is used, or if the stocked eels used are yellow eel from aquaculture. We evaluated the yield from stocking two different sizes, 3 and 9 g eels from aquaculture. A professional fishery recaptured 12.7% of the 3 g and 9.4% of the 9 g eels, originally stocked. Growth rate and mortality rate were different for the two stocked sizes, favouring the small eels. Brutto yield per recruit (YPR) was 13 and 9.2 g and netto YPR was 9.8 and 0.31 g for 3 and 9 g eel, respectively. We conclude that there seems to be no advantage in using larger 9 g eels compared with small 3 g eels for stocking.

The effects of transecting the IXth and Xth cranial nerves on hydromineral balance in the eel Anguilla anguilla

1976 ◽  
Vol 64 (2) ◽  
pp. 461-475
Author(s):  
N. Mayer-Gostan ◽  
T. Hirano
Keyword(s):  
Fresh Water ◽  
Sea Water ◽  
Cranial Nerves ◽  
Anguilla Anguilla ◽  
Vagus Nerves ◽  
Rapid Reduction ◽  
Ion Concentrations ◽  
Excess Loss ◽  
Na Efflux ◽  
Hydromineral Balance

The IXth and the Xth cranial nerves in Anguilla anguilla were transected, and the effects upon ion and water balance were studied in fresh water and sea water, and during transfer from fresh water and vice versa. In fresh water there is a slow demineralization due to an excess loss of Na and Cl ions. During freshwater to seawater transfer the eel survives only for 4–5 days. The fish do not drink and Na efflux does not increase enough to extrude excess ions. In sea water the glossopharyngeal and vagus nerves are necessary for the maintenance of the hydromineral balance. Denervation is followed by an increase in plasma ion concentrations. Na fluxes are not modified and increased water loss is not compensated by drinking. The rapid reduction of Na efflux during transfer from sea water to fresh water is not modified by denervation.

Kinetics of Water and Chloride Exchanges During Adaptation of the European Eel to Sea Water

1973 ◽  
Vol 58 (1) ◽  
pp. 105-121
Author(s):  
R. KIRSCH ◽  
N. MAYER-GOSTAN
Keyword(s):  
Fresh Water ◽  
Sea Water ◽  
Anguilla Anguilla ◽  
Maximum Level ◽  
Progressive Increase ◽  
Plasma Sodium ◽  
European Eel ◽  
Drinking Rate ◽  
The One ◽  
Kinetics Of

Using isotopic procedures, the drinking rate and chloride exchanges were studied in the eel Anguilla anguilla during transfer from fresh water to sea water. 1. Following transfer to sea water there is a threefold increase of the drinking rate (lasting about 1 h). Then it falls to a minimum after 12-16 h and rises again to a maximum level about the seventh day after the transfer. Then a gradual reduction leads to a steady value which is not significantly different from the one observed in fresh water. 2. The changes with time of the plasma sodium and chloride concentrations are given. Their kinetics are not completely alike. 3. The chloride outflux increases 40-fold on transfer of the eel to sea water, but even so it is very low. After the sixth hour in sea water there is a progressive increase in the flux, so that on the fourth day it is higher (500 µ-equiv. h-1.100 g-1) than in the seawater-adapted animals (230 µ-equiv.h-1.100 g-1). 4. Drinking rate values in adapted animals are discussed in relation to the external medium. The kinetics of the drinking rate together with variations in body weights after freshwater-seawater transfer are discussed in relation to the possible stimulus of the drinking reflex. 5. Chloride fluxes (outflux, net flux, digestive entry) are compared and lead one to assume that in seawater-adapted fish one-third of the chloride influx enters via the gut and two-thirds via the gills.

Follicular steroidogenesis in vitro in cyclic and PMSG/hCG-treated gilts

1991 ◽  
Vol 71 (4) ◽  
pp. 1257-1260
Author(s):  
T. Wiesak ◽  
R. T. Hardin ◽  
G. R. Foxcroft ◽  
M. G. Hunter
Keyword(s):  
Key Words ◽  
Follicular Development ◽  
Steroid Production ◽  
Functional Differences ◽  
Key Words Pig

Basal steroid production in vitro by comparable follicles from cyclic and PMSG/hCG-treated gilts was similar. Follicular responses to LH in vitro varied, however, confirming earlier evidence for functional differences in the pattern of follicular development in immature gilts in response to exogenous gonadotropins compared with naturally cyclic gilts. Key words: Pig, gonadotrophin, follicle, steroidogenesis, steroids

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