Qualification of a 17β-estradiol (E2) Assay in Sprague Dawley Rat Serum

2020 ◽  
Vol 154 (Supplement_1) ◽  
pp. S85-S86
Author(s):  
J A Martin ◽  
J Figueiredo ◽  
L Wang
Keyword(s):  
Hemoglobin Concentration ◽  
Female Rats ◽  
Sprague Dawley ◽  
Serum Samples ◽  
Rat Serum ◽  
Data Set ◽  
A Value ◽  
Male And Female Rats ◽  
17Β Estradiol ◽  
Assay Precision

Abstract Introduction/Objective Significant technical issues are associated with methods used for the measurement of estradiol.The objective of this study was to qualify an electrochemiluminescent (ECL) assay for the quantification of 17β-estradiol (E2) in rat serum. Hemolysis has been identified as a factor that interferes with accurate measurement.The impact of hemolysis was also assessed. Methods Approximately 1.0 mL of whole blood was collected from male and female rats into separate red top tubes and processed to serum. The LoQ for E2 was evaluated by analyzing the low calibrator or at least 6 serum samples diluted to produce a value at the low end of the reportable range 8 times in the same run.The mean, standard deviation, and %CV were calculated for each sample.The data set was analyzed by plotting the data and determining the concentration at the intersection of the precision profile curve. Linearity of dilution was performed using commercially available calibration verification material and E2 stripped rat serum.The correlation coefficient, the slope, and the % Nominal were calculated. Intra assay precision was evaluated by analyzing 8 consecutive times in a single run one rat serum sample that was not diluted or spiked. This analysis was performed during the evaluation of the LoQ.The mean, SD and %CV were calculated. The interference of hemolysis with the E2 assay was tested by analyzing at least 5 rat serum samples/pools spiked with hemolyzed rat serum at different hemoglobin concentrations.The %RE was calculated. Results The LoQ assays were acceptable. For all samples tested, the % CV was less than or equal to 25%.The LoQ was verified to be 8.50 pg/mL. The %CV was 15.6%. For samples with estradiol concentrations below the LoQ, a value of 4.25 pg/ml was reported. Linearity of dilution for E2 was acceptable.The correlation coefficients were greater than or equal to 0.9000, the slopes were between 0.7500 and 1.2500, and the % nominals for each level were between 75-125%. The intra-assay precision was considered acceptable with a %CV of 8.6%. There was no hemolysis interference in the assay when samples were spiked with hemoglobin concentrations of up to 70 mg/dL, based on the %RE of less than or equal to 25% of non-hemolyzed samples. Conclusion Qualification of the ECL method, demonstrates the assay is suitable for the determination of E2 in serum samples from rats and absence of hemolysis interference up to 70 mg/dL of hemoglobin concentration.

scholarly journals Isolation and Quantification of Sphingosine and Sphinganine from Rat Serum Revealed Gender Differences

Biomolecules ◽  
2019 ◽  
Vol 9 (9) ◽  
pp. 459 ◽  
Author(s):  
Graham Brogden ◽  
Diab M. Husein ◽  
Pablo Steinberg ◽  
Hassan Y. Naim
Keyword(s):  
High Performance ◽  
Gene Mutations ◽  
Female Rats ◽  
Sphingolipid Metabolism ◽  
Female Rat ◽  
Serum Samples ◽  
Fluorescence Detector ◽  
Rat Serum ◽  
Male And Female Rats ◽  
Significant Difference

Sphingolipids are an important group of lipids that play crucial roles in living cells, facilitating cell recognition, signal transduction and endocytosis. The concentration of sphingosine and some of its derivatives like sphinganine may serve as a biomarker for the diagnosis of sphingolipidoses or be used for further research into similar diseases. In this study, a sphingolipid extraction and a high resolution detection method specific for sphingosine and sphinganine was adapted and tested. Lipids were extracted from rats’ serum, coupled to o-phthalaldehyde and detected with a fluorescence detector after running through a silica gel column in a high performance liquid chromatography system. With this method, we analysed 20 male and 20 female rat serum samples and compared the concentrations of sphingosine and sphinganine. The results showed a significant difference between the sphingosine concentrations in the male and female rats. The sphingosine concentration in female rats was 805 ng/mL (standard deviation, SD ± 549), while that in males was significantly lower at (75 ng/mL (SD ± 40)). Furthermore, the sphingosine:sphinganine ratio was almost 15-fold higher in the females’ samples. The method presented here facilitates the accurate quantification of sphingosine and sphinganine concentrations down to 2.6 ng and 3.0 ng, respectively, and their ratio in small amounts of rat serum samples to study the sphingolipid metabolism and its potential modulation due to gene mutations or the effect of prevalent toxins.

scholarly journals Effects of ovariectomy and estrogen on ischemia-reperfusion injury in hindlimbs of female rats

2001 ◽  
Vol 91 (4) ◽  
pp. 1828-1835 ◽  
Author(s):  
Nicole Stupka ◽  
Peter M. Tiidus
Keyword(s):  
Muscle Damage ◽  
Ischemia Reperfusion Injury ◽  
Serum Insulin ◽  
Ischemia Reperfusion ◽  
Neutrophil Infiltration ◽  
Female Rats ◽  
Protective Effects ◽  
Sprague Dawley ◽  
Sprague Dawley Rats ◽  
17Β Estradiol

The effects of estrogen and ovariectomy on indexes of muscle damage after 2 h of complete hindlimb ischemia and 2 h of reperfusion were investigated in female Sprague-Dawley rats. The rats were assigned to one of three experimental groups: ovariectomized with a 17β-estradiol pellet implant (OE), ovariectomized with a placebo pellet implant (OP), or control with intact ovaries (R). It was hypothesized that following ischemia-reperfusion (I/R), muscle damage indexes [serum creatine kinase (CK) activity, calpain-like activity, inflammatory cell infiltration, and markers of lipid peroxidation (thiobarbituric-reactive substances)] would be lower in the OE and R rats compared with the OP rats due to the protective effects of estrogen. Serum CK activity following I/R was greater ( P < 0.01) in the R rats vs. OP rats and similar in the OP and OE rats. Calpain-like activity was greatest in the R rats ( P < 0.01) and similar in the OP and OE rats. Neutrophil infiltration was assessed using the myeloperoxidase (MPO) assay and immunohistochemical staining for CD43-positive (CD43+) cells. MPO activity was lower ( P < 0.05) in the OE rats compared with any other group and similar in the OP and R rats. The number of CD43+ cells was greater ( P < 0.01) in the OP rats compared with the OE and R rats and similar in the OE and R rats. The OE rats had lower ( P < 0.05) thiobarbituric-reactive substance content following I/R compared with the R and OP rats. Indexes of muscle damage were consistently attenuated in the OE rats but not in the R rats. A 10-fold difference in serum estrogen content may mediate this. Surprisingly, serum CK activity and muscle calpain-like activity were lower ( P< 0.05) in the OP rats compared with the R rats. Increases in serum insulin-like growth factor-1 content ( P < 0.05) due to ovariectomy were hypothesized to account for this finding. Thus both ovariectomy and estrogen supplementation have differential effects on indexes of I/R muscle damage.

scholarly journals Toxicity Evaluation of a Traditional Polyherbal Unani Formulation Jawarish Shahi in Rats

2018 ◽  
Vol 7 (5) ◽  
pp. 412-418
Author(s):  
Mohd Urooj ◽  
◽  
Mohammad Ahmed Khan ◽  
G. Thejaswini ◽  
Munawwar Husain Kazmi ◽  
...  
Keyword(s):  
Body Weight ◽  
Feed Intake ◽  
Clinical Signs ◽  
Female Rats ◽  
Control Group ◽  
Sprague Dawley ◽  
Male And Female ◽  
Salix Caprea ◽  
Male And Female Rats ◽  
Dose Levels

Jawarish Shahi (JS) is a compound polyherbal Unani pharmacopoeial formulation indicated for Khafqan (Palpitation), Nafkh-e-Shikam (Flatulence) and Waswas (Insanity; false perception and hallucinations). Jawarish Shahi contains herbs like Halela (Terminalia chebula), Amla (Emblica officinalis), Kishneez (Coriandrum sativum), Elaichi Khurd, (Elettaria cardamomum), and Bed Mushk (Salix caprea). The present study was carried out as per OECD 408 guidance to evaluate 90 days repeated oral dose toxicity in male and female Sprague Dawley rats. The study was performed at dose levels 1028 and 2000 mg/kg bw. No adverse effects were reported with respect to body weight, feed intake, behavior and clinical signs indicative of systemic toxicity. The expected growth pattern was observed in body weight and feed intake as compared to control group at both dose levels in male and female rats. There were few significant alterations with respect to hematology, and clinical biochemistry, however the results were within normal range thus considered toxicologically insignificant. The microscopic examination of different organ/tissue showed that no histopathological changes were observed. The findings of the study showed that No Observed Adverse Effect Level (NOAEL) for JS is greater than 2000 mg/kg body weight

Dietary Administration of Colesevelam Hydrochloride Does Not Affect Fertility or Reproductive Performance in Rats

2004 ◽  
Vol 23 (6) ◽  
pp. 357-367 ◽  
Author(s):  
Judith K. Marquis ◽  
Rafif Dagher ◽  
Michael R. Jones
Keyword(s):  
Reproductive Performance ◽  
Sperm Count ◽  
Embryo Implantation ◽  
Sperm Concentration ◽  
Study Groups ◽  
Female Rats ◽  
Corpora Lutea ◽  
Sprague Dawley ◽  
Total Percentage ◽  
Male And Female Rats

Colesevelam hydrochloride (HCl) (WelChol; Sankyo Pharma) is a novel, highly potent, bile acid-binding polymer used for the treatment of hypercholesterolemia. The primary aim of this study was to determine the effects of dietarily administered colesevelam HCl on fertility and reproductive performance parameters. To assess these effects, sexually mature Sprague-Dawley rats were randomized to one of five treatment groups: feed alone, feed plus control article (SigmaCell), or feed plus colesevelam HCl 200, 1000, or 2000 mg/kg/day. Male and female rats were administered the appropriate group agent for 28 and 15 days, respectively, and were subsequently paired together for cohabitation and mating. Females continued to receive the test agent in their dietary formulation through presumed gestation day (GD) 7. Presumed pregnant females underwent cesarean section on GD 20. Food consumption rate, body weight, gross necropsy, and standard preclinical tests for reproduction and fertility were performed for each test animal. No statistically significant differences were found between control and drug-treated groups for any tested endpoints of reproduction. All animals placed in cohabitation successfully mated. Uterine and litter end points were unaffected by dosages of colesevelam HCl as high as 2000 mg/kg/day. There were no significant differences between treatment group litter averages in the number of corpora lutea, implantation sites, litter size, live fetuses, body weights, early/late resorptions, and the number of dams with viable fetuses. In addition, no external alterations of fetal morphology were attributable to treatment with colesevelam HCl when administered up to the embryo implantation stage. In male animals, no significant differences were found between the colesevelam HCl and control study groups in the average caudal epididymal sperm count or sperm concentration, total number of motile and nonmotile sperm, and the total percentage of motile sperm. Based on these data, colesevelam HCl does not have any significant adverse reproductive or fertility effects in rats, even when administered at doses approximately 30 times greater than the approved clinical dose.

scholarly journals A Safety Evaluation of a Nature-Identical l-Ergothioneine in Sprague Dawley Rats

2016 ◽  
Vol 35 (5) ◽  
pp. 568-583 ◽  
Author(s):  
Palma Ann Marone ◽  
Jan Trampota ◽  
Steven Weisman
Keyword(s):  
Body Weight ◽  
Body Weight Gain ◽  
Antioxidant Properties ◽  
Metabolic Activation ◽  
Female Rats ◽  
Systemic Absorption ◽  
Test Substance ◽  
Sprague Dawley ◽  
Male And Female Rats ◽  
Sprague Dawley Rats

l-(+) Ergothioneine is a naturally occurring thiol amino acid with antioxidant properties and potential benefits as a dietary supplement. Despite its century-old identification and wide distribution in human food, little is known of its mechanism of action and safety. The nature-identical biomimetic of l-(+) ergothioneine, produced by Mironova Labs and supplied as Mironova (EGT+), has been investigated in the present studies for its mutagenic and toxicologic potential. In a plate incorporation and preincubation assay with Salmonella typhimurium strains TA98, 100, 1,535, and 1,537 and Escherichia coli WP2uvrA strain, at dose concentrations of 1.58, 5, 15.8, 50, 158, 500, 1,580, and 5,000 μg/plate with and without metabolic activation, no cytotoxicity or mutagenicity was observed. Following a preliminary 28-day study, a repeated dose 90-day gavage study at dose levels of 0, 400, 800, and 1,600 mg/kg body weight (bw)/d in Sprague Dawley rats, in which dose-proportional systemic absorption was confirmed by plasma analysis, no adverse clinical, body weight/gain, food consumption and efficiency, clinical pathology, or histopathological changes associated with the administration of the nature-identical ergothioneine were observed. In conclusion, EGT+ administered over 90 days was well tolerated with a no adverse effect level at 1,600 mg/kg bw/d, the highest dose tested for male and female rats. In addition, the nature-identical test substance, EGT+ was not mutagenic in a bacterial reverse mutation assay at plate concentrations of up to 5,000 μg/mL in the presence or absence of metabolic activation.

scholarly journals Absorption, Distribution, Excretion, and Pharmacokinetics ofC-Pyronaridine Tetraphosphate in Male and Female Sprague-Dawley Rats

2010 ◽  
Vol 2010 ◽  
pp. 1-9 ◽  
Author(s):  
Sang Hyun Park ◽  
Kannampalli Pradeep
Keyword(s):  
Clinical Trials ◽  
Small Intestine ◽  
Oral Administration ◽  
Female Rats ◽  
Sprague Dawley ◽  
Male And Female ◽  
Phase Ii Clinical Trials ◽  
Male And Female Rats ◽  
Sprague Dawley Rats ◽  
Peak Value

The main objective of this investigation was to determine the absorption, distribution, excretion, and pharmacokinetics of the antimalarial drug pyronaridine tetraphosphate (PNDP) in Sprague-Dawley rats. Following oral administration of a single dose (10 mg/Kg) ofC-PNDP, it was observed that the drug was readily absorbed from the small intestine within 1 hour following oral administration and was widely distributed in most of the tissues investigated as determined from the observed radioactivity in the tissues. The peak value of the drug in the blood was reached at around 8 hours postadministration, and radioactivity was detected in most of the tissues from 4 hours onwards.C-PNDP showed a poor permeability across the blood-brain barrier, and the absorption, distribution, and excretion ofC-PNDP were found to be gender-independent as both male and female rats showed a similar pattern of radioactivity. Excretion of the drug was predominantly through the urine with a peak excretion post 24 hours of administration. A small amount of the drug was also excreted in the feces and also in the breath. It was found that theCmax, AUC (0-inf), andTmaxvalues were similar to those observed in the Phase II clinical trials of pyronaridine/artesunate (Pyramax) conducted in Uganda.

EFFECT OF NEONATAL ADMINISTRATION OF THYROXINE ON THE RATE OF SEBUM PRODUCTION IN RATS

1979 ◽  
Vol 83 (2) ◽  
pp. 199-203 ◽  
Author(s):  
YEE CHU TOH
Keyword(s):  
Normal Activity ◽  
Skin Surface ◽  
Postnatal Period ◽  
Female Rats ◽  
Sprague Dawley ◽  
Male And Female Rats ◽  
Sprague Dawley Rats ◽  
Sebum Production ◽  
Skin Surface Lipids ◽  
Neonatal Administration

Newborn Sprague–Dawley rats of both sexes were treated with 28 μg thyroxine (T4) daily for the first week of life. At the age of 80 days, the secretion rate of sebum was measured from the amount of skin-surface lipids extractable by acetone and which had been produced during 2 days. Treatment with such excess amounts of T4 during the early postnatal period significantly reduced the production of sebum in both male and female rats when compared with control rats and with rats deprived of food early in life. The thyroid, the pituitary gland, the testes and the seminal vesicles were significantly smaller but the weights of the ovaries and uteri remained relatively unaffected. There was a similar ratio of sex difference in the rate of sebum secretion irrespective of treatment. It is suggested that a reduction of sebaceous response in rats made thyrotoxic with large doses of T4 early in life was probably due to a decreased secretion of thyroid hormone which is required to maintain normal activity of the sebaceous glands.

ROLE OF THE GONADS IN THE REGULATION OF SEBACEOUS GLANDS IN RATS: COMPARISON OF THE EFFECTS OF CASTRATION AT AND AFTER BIRTH

1980 ◽  
Vol 85 (2) ◽  
pp. 261-265 ◽  
Author(s):  
YEE CHU TOH
Keyword(s):  
Skin Surface ◽  
Female Rats ◽  
Sprague Dawley ◽  
Sebaceous Glands ◽  
Male And Female Rats ◽  
Sprague Dawley Rats ◽  
Sequential Event ◽  
Sebum Production ◽  
Skin Surface Lipids

Sprague–Dawley rats were castrated either within 24 h of birth or at 4 weeks of age. Control animals were sham operated. Intact female rats were also included for comparison. Sebum production was assessed at 80 days of age by measuring the amount of skin-surface lipids that could be extracted with acetone and which had been produced during 2 days. The removal of the testes at birth reduced the activity of the sebaceous glands to a level more nearly approaching that seen in the female rats whereas castration at 4 weeks of age only partially decreased the rate of sebum secretion so that it was intermediate between the male and female rats. The weights of the pituitary gland, thyroid and adrenal glands increased after castration but there were no differences between rats castrated at birth and those castrated at 4 weeks of age except in the weight of the thyroid gland. It would appear that the role of the testes in the control of the activity of the sebaceous glands is a sequential event which has already started at birth.

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