Analyze Diet

Topic:Analytical Methods

Analytical methods in equine research encompass a variety of scientific techniques and tools used to study and evaluate different aspects of horse health, performance, and physiology. These methods help advance our understanding of equine biology, diagnosing conditions, and improving management practices. Common analytical methods include molecular techniques like PCR and ELISA for detecting pathogens and measuring biomarkers, imaging technologies such as ultrasound and MRI for assessing musculoskeletal health, and statistical models for analyzing genetic data and performance metrics. This page compiles peer-reviewed research studies and scholarly articles that explore the development, application, and impact of various analytical methods in equine science.
Performance of a manually operated salad spinner centrifuge for serum separation in the healthy domestic horse (Equus caballus) and southern white rhinoceros (Ceratotherium simum).
Veterinary clinical pathology    July 26, 2023   doi: 10.1111/vcp.13290
Cassady KR, Minter LJ, Gruber EJ.Field veterinarians and researchers studying wild species, such as the southern white rhinoceros, often work in remote areas with limited access to standard laboratory equipment, hindering the ability to measure serum analytes. Objectives: The first objective was to produce an inexpensive, manually operated centrifuge that could accept standard laboratory tubes by modifying a consumer-grade salad spinner with low-cost materials. The second objective was to compare biochemistry analysis results obtained from equine and southern white rhinoceros serum separated by traditional laboratory and m...
First evidence of the incorporation of daprodustat and other hypoxia-inducible factor stabilizers into equine hair by passive transfer based on segmental quantitative analysis.
Journal of pharmaceutical and biomedical analysis    July 24, 2023   Volume 235 115600 doi: 10.1016/j.jpba.2023.115600
Ishii H, Shibuya M, Kusano K, Sone Y, Kamiya T, Wakuno A, Ito H, Miyata K, Yamada M, Leung GN.Daprodustat is a hypoxia-inducible factor prolyl hydroxylase domain (HIF-PHD) inhibitor and is used as an erythropoiesis stimulant for the treatment of anemia in humans. In general, administering daprodustat to horses will result in a lifetime ban from both equestrian sports and horseracing by the International Federation of Horseracing Authorities and the Fédération Équestre Internationale, respectively. To control the misuse/abuse of daprodustat, we conducted nasoesophageal administration of daprodustat (100 mg/day for 3 days) to three thoroughbred mares and the post-administration hair ...
Detecting SNP markers discriminating horse breeds by deep learning.
Scientific reports    July 18, 2023   Volume 13, Issue 1 11592 doi: 10.1038/s41598-023-38601-z
Manzoori S, Farahani AHK, Moradi MH, Kazemi-Bonchenari M.The assignment of an individual to the true population of origin using a low-panel of discriminant SNP markers is one of the most important applications of genomic data for practical use. The aim of this study was to evaluate the potential of different Artificial Neural Networks (ANNs) approaches consisting Deep Neural Networks (DNN), Garson and Olden methods for feature selection of informative SNP markers from high-throughput genotyping data, that would be able to trace the true breed of unknown samples. The total of 795 animals from 37 breeds, genotyped by using the Illumina SNP 50k Bead ch...
A hydrophobic deep eutectic solvent-based vortex-assisted liquid-liquid microextraction applied for doping control of aromatase inhibitors from equine urine.
Journal of pharmaceutical and biomedical analysis    July 14, 2023   Volume 234 115583 doi: 10.1016/j.jpba.2023.115583
Chen Q, Wang Z, Chen H.Aromatase inhibitors (AIs) can indirectly cause increased testosterone in animals, which leads to the improvement of the athletic ability of horses. For the protection of horses and the consideration of fair competition, AIs were listed as prohibited drugs by the Federation Equestre Internationale (FEI). There were several disadvantages using traditional pretreatment methods before analyzing these drugs from biological samples. A rapid and green pretreatment method has been developed by utilizing the hydrophobic deep eutectic solvent (DES)-based vortex-assisted liquid-liquid microextraction (D...
Agreement between hematocrit values determined by the Cobas b121 blood gas analyzer and the microhematocrit method in dogs, cats, and horses.
Veterinary clinical pathology    July 12, 2023   doi: 10.1111/vcp.13245
Dallarosa P, Monteiro ER, Borenstein APS, Valle SF.Packed cell volume (PCV) is important for assessing a patient's health status. Some blood gas analyzers measure hematocrit, and the agreement with PCV varies among different analyzers. Objective: We aimed to determine the agreement between PCV measured by microcentrifugation and hematocrit measured by the Cobas b121 blood gas analyzer in dogs, cats, and horses. Methods: Whole blood samples for PCV and blood gas analysis were collected in lithium-heparin syringes and analyzed within 10 min of collection. Agreement and association between the PCV and Cobas b121 generated hematocrit were assess...
Identification of the dermorphin tetrapeptide [Dmt1 ]-DALDA in a seized unlabelled vial and its first detection in horse urine: A case report.
Drug testing and analysis    July 5, 2023   doi: 10.1002/dta.3536
Choi TLS, Lau MY, Wong JKY, Wan TSM, Ho ENM.No abstract available
Screening and confirmation of recombinant human follistatin in equine plasma for doping control purposes.
Drug testing and analysis    July 4, 2023   doi: 10.1002/dta.3540
Wong KS, Cheung HW, Choi YC, To NS, Wan TSM, Ho ENM.Recombinant human follistatin (rhFST) is a potential performance-enhancing agent owing to its stimulating effect on muscle growth. Administration of rhFST to athletes is prohibited in human sports by the World Anti-Doping Agency (WADA) and in horseracing according to Article 6 of the International Agreement on Breeding, Racing and Wagering published by the International Federation of Horseracing Authorities (IFHA). For effective control of the potential misuse of rhFST in flat racing, methods for screening and confirmatory analysis are required. This paper describes the development and validat...
Applicability of 2,4-dinitrophenylhydrazine (DNPH) method of protein oxidative damage measurement in the seminal plasma of canine ( Canis lupus familiaris) and stallion ( Equus caballus).
Polish journal of veterinary sciences    June 30, 2023   Volume 26, Issue 2 177-184 doi: 10.24425/pjvs.2023.145020
Mogielnicka-Brzozowska M, Woźniak MJ, Cichowska AW, Fraser L, Kraziński B, Strzezek R, Zielińska D.Seminal plasma (SP) proteins are responsible for sperm functional quality. Developing a reliable method to determine the degree of oxidative damage of these proteins is important for establishing semen fertilizing ability. The main aim of the study was to verify the applicability of protein carbonyl derivatives measurement in the SP of canine and stallion, using a method with 2,4-dinitrophenylhydrazine (DNPH). The research material consisted of ejaculates obtained from eight English Springer Spaniels, and from seven half-blood stallions during the breeding and non-breeding season. The content ...
High-throughput untargeted screening of biotherapeutic macromolecules in equine plasma by UHPLC-HRMS/MS: Application to monoclonal antibodies and Fc-fusion proteins for doping control.
Drug testing and analysis    June 20, 2023   doi: 10.1002/dta.3525
Pinetre J, Delcourt V, Becher F, Garcia P, Barnabé A, Loup B, Popot MA, Fenaille F, Bailly-Chouriberry L.Many innovative biotherapeutics have been marketed in the last decade. Monoclonal antibodies (mAbs) and Fc-fusion proteins (Fc-proteins) have been developed for the treatment of diverse diseases (cancer, autoimmune diseases, and inflammatory disorders) and now represent an important part of targeted therapies. However, the ready availability of such biomolecules, sometimes characterized by their anabolic, anti-inflammatory, or erythropoiesis-stimulating properties, raises concerns about their potential misuse as performance enhancers for human and animal athletes. In equine doping control labo...
Simultaneous Determination of Pyrethrins, Pyrethroids, and Piperonyl Butoxide in Animal Feeds by Liquid Chromatography-Tandem Mass Spectrometry.
Toxins    June 17, 2023   Volume 15, Issue 6 401 doi: 10.3390/toxins15060401
Xu X, Murphy LA.The presence of insecticides like pyrethrins and synthetic pyrethroids, combined with the synergist piperonyl butoxide, in animal feeds can pose a risk to both animal and human health by contaminating the food chain. In this study, a simple and fast method was developed for the simultaneous determination of these compounds in contaminated animal feeds using liquid chromatography-tandem mass spectrometry (LC-MS/MS). Sample preparation was carried out using a QuEChERS-based approach, and the method was validated with acceptable accuracy ranging from 84 to 115% and precision below 10%. The limit ...
Long-term monitoring of clodronate in equine hair using liquid chromatography-tandem mass spectrometry.
Journal of chromatography. B, Analytical technologies in the biomedical and life sciences    June 16, 2023   Volume 1226 123789 doi: 10.1016/j.jchromb.2023.123789
Knych HK, McKemie DS, Yim S, Stanley SD, Arthur RM.Given the potential for long-term inhibition of bone remodeling/healing and detrimental effects to horses in training, bisphosphonates are tightly regulated in horseracing. Hair has proven to be an effective matrix for detection of drug administration to horses and has been particularly effective in detecting drugs for a long period of time post administration. Thus, hair may prove to be a useful matrix for detection of administration of this class of drugs. The objective of the current study was to develop an assay and assess the usefulness of hair as a matrix for long-term detection of clodr...
Characterization of the Glycans of Equine κ-Casein.
Journal of agricultural and food chemistry    June 6, 2023   Volume 71, Issue 24 9460-9468 doi: 10.1021/acs.jafc.3c00452
Jaeser M, Wunderlich C, Henle T.To study the protein-bound glycans of equine κ-casein, equine sodium caseinate was first obtained from raw mare's milk by acid precipitation and then fractionated by cation-exchange chromatography. The oligosaccharides of the obtained equine κ-casein were analyzed by RP-HPLC-UV-HRMS after β-elimination with simultaneous derivatization with 1-phenyl-3-methyl-5-pyrazolone (PMP). In addition to the acidic tetrasaccharide derivative Neu5Ac-Gal-[Neu5Ac]-GalNAc-2PMP known from bovine κ-casein, the acidic pentasaccharide derivative Neu5Ac-Gal-[Gal-GlcNAc]-GalNAc-2PMP was identified as the most ab...
A review of current chemistry, pharmacology, and regulation of endogenous anabolic steroids testosterone, boldenone, and nandrolone in horses.
Journal of veterinary pharmacology and therapeutics    June 1, 2023   Volume 46, Issue 4 201-217 doi: 10.1111/jvp.13397
Dirikolu L, Lehner AF.Anabolic androgenic steroids are synthetic substances related to the male sex hormones (androgens). These agents promote the growth of skeletal muscle (anabolic effects) and the development of male sexual characteristics (androgenic effects). Anabolic steroids have been illegally used for many years as performance-enhancing drugs in human, equine, and canine sports and as growth promoters in livestock reared to provide meat for human consumption. The analytical challenge to developing effective means of control within these fields has been exacerbated by the reported endogenous nature of some ...
Detection of boldenone in the urine of female horses-ex vivo formation versus administration.
Drug testing and analysis    June 1, 2023   doi: 10.1002/dta.3521
Viljanto M, Kaabia Z, Taylor P, Hincks P, Muir T, Habershon-Butcher J, Bailly-Chouriberry L, Scarth J.Boldenone is an anabolic-androgenic steroid (AAS) that is prohibited in equine sports. However, in certain situations, it is endogenous, potentially formed by the microbes in urine. An approach to the differentiation based on the detection of the biomarkers Δ1-progesterone, 20(S)-hydroxy-Δ1-progesterone and 20(S)-hydroxyprogesterone was assessed, and their concentrations were monitored in the urine of untreated female horses (n = 291) alongside boldenone, boldienone, testosterone and androstenedione. Using an ultra-sensitive analytical method, boldenone (256 ± 236 pg/mL, n = 2...
Identification of erythropoietin mimetic peptide 1 linear form in a sealed vial and its administration study in horses for doping control purpose.
Drug testing and analysis    May 29, 2023   doi: 10.1002/dta.3522
So YM, Wong JKY, Wong ASY, Tse ATL, Wan TSM, Ho ENM.The erythropoietin mimetic peptide 1 linear form (EMP1-linear), GGTYSCHFGPLTWVCKPQGG-NH , was identified in an unknown preparation consisting of white crystalline powder contained in sealed glass vials using ultrahigh performance liquid chromatography-high-resolution mass spectrometry (UPLC-HRMS). The white crystalline powder, allegedly used for doping racehorses, was found to contain around 2% (w/w) of EMP1-linear. EMP1-linear can be cyclised in equine plasma at physiological temperature of 37°C by forming an intramolecular disulfide bond to give EMP1, which is a well-known erythropoiesis st...
Prolonged holding time and sampling protocol affects viscoelastic coagulation parameters as measured by the VCM-Vet™ using fresh equine native whole blood.
American journal of veterinary research    May 27, 2023   Volume 84, Issue 6 ajvr.23.02.0039 doi: 10.2460/ajvr.23.02.0039
Díaz Yucupicio S, Bishop RC, Fick ME, Austin SM, Barger AM, Stolsworth B, Wilkins PA.Determine the effect of sample holding time and single sample reuse on viscoelastic coagulation parameters when using fresh equine native whole blood. Methods: 8 healthy adult horses from a university teaching herd. Methods: Blood collected by direct jugular venipuncture (18 ga needle, 3 mL syringe) was held at 37 °C for 2, 4, 6, or 8 minutes according to 1 of 2 protocols. Syringes were gently inverted twice, a small amount of blood was expressed, testing cartridges were filled, and placed within the VCM-Vet™ device (Entegrion Inc). Protocol A: samples were processed from a single syringe. ...
Equine in vivo metabolite profiling of the selective androgen receptor modulator LGD-3303 for doping control.
Journal of pharmaceutical and biomedical analysis    May 18, 2023   Volume 233 115468 doi: 10.1016/j.jpba.2023.115468
Broberg MN, Knych H, Bondesson U, Pettersson C, Tidstedt B, Stanley S, Thevis M, Hedeland M.LGD-3303 is a Selective Androgen Receptor Modulator (SARM) that is prohibited in both equine and human sports due to its anabolic properties. The aim of this study was to investigate the equine in vivo metabolite profile of LGD-3303 and identify drug metabolites that can be suitable as new and improved analytical targets for equine doping control. This was performed by an oral administration of 0.05 mg·kg LGD-3303 to horses, where blood and urine samples were collected up to 96 h after administration. The in vivo samples consisting of plasma, urine and hydrolyzed urine were analyzed utilizi...
Detection of gonadotropin-releasing hormone and its analogues in equine and canine urine by high-resolution data-independent acquisition.
Drug testing and analysis    May 3, 2023   Volume 15, Issue 8 896-908 doi: 10.1002/dta.3486
Timms M, Botteon A, Manos C, Griffin J, Levina V, Steel R.Gonadotropin-releasing hormone (GnRH) and its synthetic analogues are considered banned substances by the racing industry. GnRH is used as a pharmaceutical to regulate the female oestrous cycle, but the hormone is also thought to increase the production of testosterone in male animals. Using liquid chromatography in conjunction with high-resolution mass spectrometry (LC-HRMS) and data-independent acquisition (DIA), a method is presented for the detection of intact and truncated peptides of GnRH and its analogues down to the low picogram level in equine urine. The study of the catabolism of GnR...
Proteotypic peptides of hairs for the identification of common European domestic and wild animal species revealed by in-sample protein digestion and mass spectrometry analysis.
Journal of separation science    May 3, 2023   Volume 46, Issue 13 e2300064 doi: 10.1002/jssc.202300064
Kuckova S, Smirnova TA, Straka D, Meledina A, Santrucek J, Humpolakova K, Hoskova M, Cejnar P, Hynek R.The aim of this work is to offer an alternative or complementary analytical tool to the time-consuming and expensive methods commonly used for the recognition of animal species according to their hair. The paper introduces a simple and fast way for species differentiation of animal hairs called in-sample digestion. A total of 10 European animal species, including cat, cow, common degu, dog, fallow deer, goat, horse, sika deer, rabbit, roe deer, and 17 different breeds of dogs were examined using specific tryptic cleavage directly in hair followed by matrix-assisted laser desorption/ionization-...
Electrospray ionization mass spectrometry adduct formation by mobile phase additives: A case study using nitrile functional groups containing selective androgen receptor modulators.
Rapid communications in mass spectrometry : RCM    May 1, 2023   Volume 37, Issue 14 e9530 doi: 10.1002/rcm.9530
Karatt TK, Muhammed Ajeebsanu M, Karakka Kal AK, Subhahar MB, Sathiq MA, Laya S.The formation of mass adducts is common during electrospray ionization mass spectrometry (ESI-MS). However, the mechanism that leads to adduct formation is poorly understood and difficult to control. Multiplication of mass adducts at once will adversely impact the sensitivity of mass analysis and cause misinterpretation of the level of detection. Prior studies on selective androgen receptor modulators (SARMs) revealed an immense mass adduct formation in both positive and negative ESI modes. Methods: In this study, additives in the mobile phases are investigated as a potential means of controll...
Validation of an ELISA kit to measure allopregnanolone in human and equine hair. Peric T, Ellero L, Comin A, Pividori I, Prandi A.In humans, allopregnanolone plays important roles in a number of different neurodegenerative disorders, and it has been proposed for use in some therapies. Horses are commonly used as animal models for human neurodegenerative diseases, mental and behavioral disorders, and neuropsychiatric disorders, and there is interest in using hair as a biological sample to study hormones in these conditions. We validated the use of a commercial ELISA kit (DetectX allopregnanolone kit; Arbor Assays), which was designed for serum, plasma, feces, urine, and tissue samples, to assess allopregnanolone in hair s...
Changes in Calprotectin (S100A8-A9) and Aldolase in the Saliva of Horses with Equine Gastric Ulcer Syndrome.
Animals : an open access journal from MDPI    April 16, 2023   Volume 13, Issue 8 doi: 10.3390/ani13081367
Muñoz-Prieto A, Contreras-Aguilar MD, Cerón JJ, Ayala de la Peña I, Martín-Cuervo M, Eckersall PD, Holm Henriksen IM, Tecles F, Hansen S.Equine gastric ulcer syndrome (EGUS) is a highly prevalent disease that affects horses worldwide. Within EGUS, two different forms have been described: equine squamous gastric disease (ESGD) and equine glandular gastric disease (EGGD). The associated clinical signs cause detrimental activity performance, reducing the quality of life of animals. Saliva can contain biomarkers for EGUS that could be potentially used as a complementary tool for diagnosis. The objective of this work was to evaluate the measurements of calprotectin (CALP) and aldolase in the saliva of horses as potential biomarkers ...
Performance assessment of an equine metabolomics model for screening a range of anabolic agents.
Metabolomics : Official journal of the Metabolomic Society    April 7, 2023   Volume 19, Issue 4 38 doi: 10.1007/s11306-023-01985-0
Cloteau C, Dervilly G, Loup B, Delcourt V, Kaabia Z, Bagilet F, Groseille G, Dauriac K, Fisher S, Popot MA, Garcia P, Le Bizec B, Bailly-Chouriberry L.Despite their ban, Anabolic Androgenic Steroids (AAS) are considered as the most important threat for equine doping purposes. In the context of controlling such practices in horse racing, metabolomics has emerged as a promising alternative strategy to study the effect of a substance on metabolism and to discover new relevant biomarkers of effect. Based on the monitoring of 4 metabolomics derived candidate biomarkers in urine, a prediction model to screen for testosterone esters abuse was previously developed. The present work focuses on assessing the robustness of the associated method and def...
Identification of Five Gelatins Based on Marker Peptides from Type I Collagen by Mass Spectrum in Multiple Reaction Monitoring Mode.
Journal of agricultural and food chemistry    April 3, 2023   Volume 71, Issue 14 5851-5860 doi: 10.1021/acs.jafc.3c00151
Yang P, Bi Q, Li Y, Liao J, Ding Y, Huang D, Luo X, Huang Y, Yao C, Zhang J, Wei W, Li Z, Meng J, Guo D.In this study, a novel pseudo-targeted peptidomics strategy, integrating the transition list generated by an in-house software (Pep-MRMer) and the retention time transfer by high-abundance ion-based retention time calibration (HAI-RT-cal), was developed to screen marker peptides of gelatins from five closely related animal species, including porcine, bovine, horse, mule, and donkey. Five marker peptides were screened from the molecular phenotypic differences of type I collagen. Furthermore, a simple and robust 10 min multiple reaction monitoring (MRM) method was established and performed well ...
Pharmacokinetics of aminocaproic acid in thoroughbred horses.
Journal of veterinary pharmacology and therapeutics    March 30, 2023   Volume 46, Issue 4 250-256 doi: 10.1111/jvp.13124
Maxwell L, McCarrel TM, Hay S, Cole C.The antifibrinolytic agent aminocaproic acid (ACA) is occasionally used prior to episodes of intense training in racehorses suffering from exercise-induced pulmonary hemorrhage. Although a previous study indicated that the drug is cleared rapidly in horses, some racetrack practitioners claim that recent adverse analytical findings for ACA in postrace samples were from ACA administrations 5-7 days before the race. The purpose of this study was to re-examine the pharmacokinetics of ACA in horses to address this apparent conundrum. Eight exercise-conditioned thoroughbred horses were administere...
In-depth metabolic study of nonsteroidal selective androgen receptor modulator GSK2881078 in thoroughbred horses and horse liver microsomes for doping control.
Drug testing and analysis    March 27, 2023   Volume 15, Issue 7 757-768 doi: 10.1002/dta.3469
Karatt TK, Sathiq MA, Laya S, Kal AKK, Subhahar MB, Muhammed Ajeebsanu MP, Philip M, Caveney MR, Graiban FM.Nonsteroidal selective androgen receptor modulators (SARMs) are a novel class of compounds that have not yet been clinically approved; however, they appear to have a better anabolic/androgenic ratio than steroids and cause slighter side effects. Sports drug testing laboratories are required to maintain continuously updated doping control analytical methods in light of the widespread misuse of SARMs in elite and amateur sports. This paper describes the metabolic conversion of SARM GSK2881078 in thoroughbred horses following oral administration and in vitro with equine liver microsomes. A liquid...
Clinical evaluation of the Immulite® 1000 chemiluminescent immunoassay for measurement of equine serum insulin.
Frontiers in veterinary science    March 27, 2023   Volume 10 1018230 doi: 10.3389/fvets.2023.1018230
Go YY, Hazard NW, Balasuriya UBR, Chapman AM, Fitton NS, Kenéz Á, Andrews FM.Accurate quantitative analysis of equine insulin in blood samples is critical for assessing hyperinsulinemia in horses. Although there are various laboratory methods for evaluating equine serum insulin, different immunoassays show significant discrepancies between the determined insulin concentrations and are often not comparable. The aim of this study was to evaluate the Immulite® 1000 chemiluminescent immunoassay (CLIA) to establish independent laboratory and assay-specific cut values to provide an accurate diagnosis of hyperinsulinemia in horses. Thus, the analytical and clinical performan...
Control of a sulfadoxine/trimethoprim combination in the competition horse: Elimination, metabolism and detection following an intravenous administration.
Drug testing and analysis    March 22, 2023   Volume 15, Issue 6 629-645 doi: 10.1002/dta.3461
Schenk I, Broussou D, Roques B, Lagershausen H, Machnik M, Röttgen H, Toutain PL, Thevis M.The combination of sulfadoxine (SDO) with trimethoprim (TMP) is widely used in veterinarian medicine. The aim of the present study was to compare excretion profiles and detection time windows of SDO and TMP in plasma and urine by means of a validated quantitative method. Eight horses received a single intravenous (i.v.) dose of 2.7 mg TMP and 13.4 mg SDO per kg bodyweight. Plasma and urine samples were collected up to 15 and 70 days post-administration, respectively. While urine samples underwent an enzymatic hydrolysis, plasma samples were proteolysed before further analysis. After solid-...
Factors affecting untargeted detection of doping agents in biological samples.
Talanta    March 11, 2023   Volume 258 124446 doi: 10.1016/j.talanta.2023.124446
Guan F, You Y, Fay S, Adreance MA, McGoldrick LK, Robinson MA.Doping control is essential for sports, and untargeted detection of doping agents (UDDA) is the holy grail for anti-doping strategies. The present study examined major factors impacting UDDA with metabolomic data processing, including the use of blank samples, signal-to-noise ratio thresholds, and the minimum chromatographic peak intensity. Contrary to data processing in metabolomics studies, both blank sample use (either blank solvent or plasma) and marking of background compounds were found to be unnecessary for UDDA in biological samples, the first such report to the authors' knowledge. The...
3-Methoxytyrosine as an indicator of dopaminergic manipulation in equine plasma.
Journal of chromatography. B, Analytical technologies in the biomedical and life sciences    March 7, 2023   Volume 1220 123652 doi: 10.1016/j.jchromb.2023.123652
Keen B, Cawley A, Reedy B, Noble G, Loy J, Fu S.The use of catechol-O-methyltransferase inhibitors may mask doping agents, primarily levodopa, administered to racehorses and prolong the stimulating effects of dopaminergic compounds such as dopamine. It is known that 3-methoxytyramine is a metabolite of dopamine and 3-methoxytyrosine is a metabolite of levodopa thus these compounds are proposed to be potential biomarkers of interest. Previous research established a urinary threshold of 4,000 ng/mL for 3-methoxytyramine to monitor misuse of dopaminergic agents. However, there is no equivalent biomarker in plasma. To address this deficiency a...
1 9 10 11 12 13 51