Induction of female-specific serum proteins in the sand lamprey,Lampetra reissneri, by exogenous estradiol-17β

1987 ◽  
Vol 34 (2) ◽  
Author(s):  
Shoichi Fukayama ◽  
Akihiko Hara ◽  
Takahiro Matsubara ◽  
Hiroya Takahashi
2001 ◽  
Vol 43 (2) ◽  
pp. 109-116 ◽  
Author(s):  
A. Tabata ◽  
S. Kashiwada ◽  
Y. Ohnishi ◽  
H. Ishikawa ◽  
N. Miyamoto ◽  
...  

Mature male medaka were continuously exposed to 0.005, 0.0–5 or 1.0 ppb of estradiol-17β (E2 or 0.1, 10 or 100 ppb of p-nonylphenol (NP) or bis-phenol-A (BPA). Female-specific proteins (Fsp) were induced in medaka exposed to 0.005 ppb of E2, 0.1 ppb of NP, or 10 ppb of BPA. Concentrations of 0.005 pbb of E2 and 0.1 ppb of NP corresponded to concentrations of these chemicals detected in river water in Japan. The abilities of the 3 chemicals to induce Fsp were E2> NP> BPA. Embryonic medaka were exposed to E2, NP and BPA under conditions of static-renewal for 200–230 days until pre-maturity. Survival ratios of medaka exposed to E2 and NP declined in concentrations more than 25 ppb and 50 ppb, respectively. The groups of medaka exposed to E2 had individuals with testis-ova or abnormal gonad. There was no male in exposure to 1.0 ppb E2. When exposed to 100 ppb of NP or BPA, abnormal gonad was also detected. Abnormal anal fin (female-like) was observed in male exposed to 100 ppb of NP. The LC50 values for each of the 3 chemicals were much higher than the concentrations detected in water in the environment—the 3 chemicals were considered to have no lethal effect on medaka in aquatic environments. However, exposures to E2 or NP at environmental concentrations induced Fsp. BPA also had the ability to affect medaka as an environmental estrogen, although its extrogenic activity was weaker than that of E2 or NP.


Langmuir ◽  
2017 ◽  
Vol 33 (45) ◽  
pp. 12926-12933 ◽  
Author(s):  
Priya S. R. Naidu ◽  
Marck Norret ◽  
Nicole M. Smith ◽  
Sarah A. Dunlop ◽  
Nicolas L. Taylor ◽  
...  

1974 ◽  
Vol 20 (12) ◽  
pp. 1548-1552 ◽  
Author(s):  
Lawrence M Killingsworth ◽  
Gregory J Buffone ◽  
Meena B Sonawane ◽  
Glennie C Lunsford

Abstract Three diluents were studied, to determine which is the best for the automated immunochemical measurement of specific serum proteins. Nine serum proteins (orosomucoid, α1-antitrypsin, α2-macroglobulin, haptoglobin, transferrin, C3, IgG, IgA, and IgM) were measured in physiological saline (9 g NaCI/liter), tris(hydroxymethyl)aminomethane buffer (0.01 mol/liter; pH 7.4), and physiological saline containing polyethylene glycol ("PEG 6000," 40 g/liter). Criteria were: reaction rate, analysis rate, carryover between samples, steady-state approximation, precision, and correlation with other methods. Saline containing polyethylene giycol is the best of the three diluents for use in continuous-flow nephelometric analysis of serum proteins.


1983 ◽  
Vol 65 (4) ◽  
pp. 337-342 ◽  
Author(s):  
R. Hoffenberg ◽  
D. B. Ramsden

1. Hormones have to be transported from their sites of synthesis to their target organs. For lipophilic hormones, such as steroids and thyroid hormones, transport is accomplished by binding to specific serum proteins, in the case of thyroxine (T4) and tri-iodothyronine (T3) to thyroxine-binding globulin (TBG) and prealbumin (PA). Normally about 70% of circulating T4 and 75–80% of T3 is bound to TBG, about 20% of T4 and 10% of T3 to PA and 10–15% of each to albumin, which has a low affinity but high capacity for both hormones [1, 2]. Apart from facilitating transport, binding to serum protein prevents excessive loss of hormone into the urine by glomerular filtration or flooding into cells, and may provide a readily available reservoir in times of need. The union between binding proteins and their ligands is reversible, so that a small proportion of hormone is non-protein-bound or ‘free’, in equilibrium with that which is protein-bound. For T4 this free fraction is normally 0.02-0.04% of the total serum T4 concentration, for T3 about 0.3% [3, 4]. 2. The major binding proteins of T4 and T3 will briefly be described and the nature of free T4 and T3 considered.


2013 ◽  
Vol 219 (1) ◽  
pp. 39-49 ◽  
Author(s):  
Hiroto Kobayashi ◽  
Saori Yoshida ◽  
Ying-Jie Sun ◽  
Nobuyuki Shirasawa ◽  
Akira Naito

Cholestasis is associated with changes in hepatic cholesterol metabolism and serum estrogen levels. Ueyama and colleagues reported that the gastric estradiol-17β (E2) level in the portal vein is several times higher than that in the artery. This study aimed to clarify the relationships between gastric E2, hepatic estrogen receptor (ER) α and cholesterol metabolism in cholestatic male rats induced by bile duct ligation (BDL). After BDL, serum E2 levels in the portal vein and artery were measured by ELISA. The gene expression of gastric estrogen-synthesizing enzymes and various hepatic enzymes for cholesterol metabolism were measured by real-time RT-PCR, and gastric aromatase and hepatic ERα proteins were determined by immunohistochemistry and western blotting. Portal E2 levels increased by 4.9, 5.0, and 3.6 times that of controls at 2 days after BDL (BDL2d), BDL4d, and BDL7d respectively. The change in arterial E2 levels was positively correlated with that in the portal vein. Under these conditions, the expression of hepatic Ers1 (ERα) mRNA and protein was significantly reduced in a negative correlation with serum E2 levels in the portal vein after BDL. The expression of hepatic male-specific cytochrome P450 (CYP) genes Cyp2c55 and Cyp3a2 decreased and female-specific Cyp2c12 increased after BDL. It is postulated that the increase in gastric E2 levels, which occurs after BDL, results in the reduction of hepatic ERα, the elevation of arterial E2 level and leads to cholesterol metabolism becoming sex steroid dependent.


2006 ◽  
Vol 18 (2) ◽  
pp. 183 ◽  
Author(s):  
D. I. Jin ◽  
H. R. Lee ◽  
H. R. Kim ◽  
H. J. Lee ◽  
J. T. Yoon ◽  
...  

To identify early pregnancy-specific serum proteins in bovine, we performed proteomics analysis using blood serum samples of pregnant and non-pregnant Holstein dairy cattle Days 21 and 35 after AI. A total of eight pregnant and eight non-pregnant cattle were used for collection of the blood samples. The global proteomics approach was exploited by the use of 2-D gel electrophoresis and mass spectrometry to sort out pregnancy-specific proteins. Serum proteins within isoelectric point ranges of 4.0 to 7.0, 6.0 to 9.0, and 5.5 to 6.7 were analyzed separately by 2-D electrophoresis with three replications of each sample. The stained gels were scanned and calibrated at an optical resolution of 63.5 �m/pixel using a GS-710 imaging densitometer (Bio-Rad Laboratories, Philadelphia, PA, USA). A total of approximately 1200 spots were detected in 2-D gels stained with Coomassie-blue. In the comparison of serum samples from pregnant and non-pregnant cattle, nine pregnancy-specific spots were detected unanimously in Day 21 and Day 35 serum samples. Pregnancy-specific proteins were identified as transferrin, albumin, IgG2a heavy chain constant region, and immunoglobulin gamma heavy chain variable region by means of MALDI-TOF-MS (PerSeptive Biosystems, Framingham, MA, USA). Even though the identified spots were abundant serum proteins, their molecular weights and pI values were different from those of the main serum proteins. Most proteins identified in this analysis appeared to be related with pregnancy-specific subunits or fragments of transferrin, albumin, and IgG. One of the pregnancy-specific proteins, transferrin, is known to be related to iron transport during pregnancy. Western blot analysis using polyclonal anti-transferrin antibody revealed specific transferrin expression in the serum samples from the pregnant cattle but no detectable expression in the serum samples from the non-pregnant cattle. Our results revealed composite profiles of key proteins involved in early pregnancy and suggest the potential use of identified proteins to detect early pregnancy in bovine.


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