Epididymis, Epithelium - Apoptosis - Nonneoplastic Lesion Atlas 288KB

https://ntp.niehs.nih.gov/atlas/nnl/reproductive-system-male/epididymis/Epithelium-Apoptosis

as a response to decreased testosterone levels. Normally, there is a low background level of apoptotic cells in the epididymis, but if testosterone levels decrease ...

Presentation: Developing AOPs from PPAR Activation Leading to... 738KB

https://ntp.niehs.nih.gov/iccvam/meetings/aop-wksp-2014/presentations/nepelska-508.pdf

Decreased testosterone stereodo genesis oestrus cycle Male reproductive tract Sperm ... steroidogenic pathway aromatase testosterone estradiol estrone Chemical initiator ...

CERHR Update on the Reproductive and Developmental Toxicity of... 4.5MB

https://ntp.niehs.nih.gov/ntp/ohat/phthalates/dehp/dehp-monograph.pdf

... tract.are.attributed.to.abnormally.low.levels.of. testosterone. induced. by. DEHP.. .........103 Table.29.. Testosterone.Metabolism.after.DEHP.Treatment.of.4.W...

Epididymis, Epithelium - Apoptosis 616KB

https://ntp.niehs.nih.gov/sites/default/files/nnl/male_reproductive/epididymis/epithapop/epididymis_epithelium_apoptosis_508_pdf.pdf

as a response to decreased testosterone levels. Normally, there is a low background level of apoptotic cells in the epididymis, but if testosterone levels decrease ...

CERHR Monograph: Potential Human Reproductive and Developmental... 6.3MB

https://ntp.niehs.nih.gov/ntp/ohat/bisphenol/bisphenol.pdf

... exposed. men.(32),.higher.levels.of.testosterone.in.men. and.women.(101, ... rodent. brain. via. aromatiza- tion.of.testosterone.secreted.from.the.fetal.and. ...

Epididymis - Hypospermia - Nonneoplastic Lesion Atlas 291KB

https://ntp.niehs.nih.gov/atlas/nnl/reproductive-system-male/epididymis/Hypospermia

Some toxicants can cause a decrease in transit time, thereby reducing normal sperm content (with no effect on spermatogenesis). Reduced testosterone levels will also result in ...

Endocrine Disruptors Low-Dose Peer Review, October 10-12, 2000 17.3MB

https://ntp.niehs.nih.gov/ntp/pressctr/mtgs_wkshps/2000/lowdosepeerfinalrpt.pdf

... "Effect of nonylphenol on serum testosterone levels and testicular steroidogenic ... on hepatic testosterone metabolism, CYP450, and estrogen receptor alpha expression." ...

Testis, Seminiferous Tubule - Retention, Spermatid - Nonneoplastic... 290KB

https://ntp.niehs.nih.gov/atlas/nnl/reproductive-system-male/testis/SeminiferousTubule-RetentionSpermatid

Spermiation is testosterone dependant, so spermatid retention also occurs with decreased intratesticular levels of testosterone. Although subtle, this finding is important to ...

TR-348: alpha-Methyldopa Sesquihydrate (CASRN 41372-08-1) in... 10.8MB

https://ntp.niehs.nih.gov/sites/default/files/ntp/htdocs/lt_rpts/tr348.pdf

... administration was probably due in part to the decreases in plasma testosterone levels. ... Decreased weight gain was also seen a t these doses. Plasma testosterone levels were ...

TOX-30: Dibutyl Phthalate (CASRN 84-74-2) 3.8MB

https://ntp.niehs.nih.gov/sites/default/files/ntp/htdocs/st_rpts/tox030.pdf

... Serum testosterone values were also lower at these concentrations than in the controls. ... was analyzed by ICP at 213.86 nm. Testosterone Concentration Analyses Serum and ...

OECD Test Guideline 441: Hershberger Bioassay in Rats: A Short... 407KB

https://ntp.niehs.nih.gov/iccvam/suppdocs/feddocs/oecd/oecd-tg441.pdf

These validation studies were conducted with a potent reference androgen (testosterone propionate (TP)), two potent synthetic androgens (trenbolone acetate and methyl testosterone), a ...

CERHR Monograph: Soy Infant Formula 122.6MB

https://ntp.niehs.nih.gov/ntp/ohat/genistein-soy/soyformula/soymonograph2010_508.pdf

... on reproductive function, i.e. fertility or permanent changes in testosterone levels. ... a signifcant effect on timing of puberty, adult plasma testosterone levels, or fertility. ...

CERHR Monograph: Potential Human Reproductive and Developmental... 5.0MB

https://ntp.niehs.nih.gov/ntp/ohat/methanol/methanol_monograph.pdf

... standard deviation SE standard error T testosterone TAS-DIET Technical Assessment System ... to fnd the inhibited spermiation lesion characteristic of reduced testosterone levels. ...

TOX-62: WY-14,643 (CASRN 50892-23-4) 2.6MB

https://ntp.niehs.nih.gov/sites/default/files/ntp/htdocs/st_rpts/tox062.pdf

... of hamsters, and concentrations of testosterone and luteinizing hormone were decreased ... hormones: estradiol, testosterone, follicle-stimulating hormone, and luteinizing hormone. ...

Addendum to ICCVAM Evaluation of In Vitro Test Methods for Detecting... 2.9MB

https://ntp.niehs.nih.gov/iccvam/docs/endo_docs/edaddendfinal.pdf

... data . testosterone propionate, also proposed for in vivo testing by EPA, was excluded because it is readily hydrolyzed in vivo to its parent compound, testosterone, which has ...

Epididymis, Duct - Atrophy - Nonneoplastic Lesion Atlas 290KB

https://ntp.niehs.nih.gov/atlas/nnl/reproductive-system-male/epididymis/Duct-Atrophy

The epididymis is an androgen-dependent tissue, and atrophy can be seen in response to decreased testosterone, decreased dihydrotestosterone (e.g., 5α-reductase inhibition), or ...

Prostate, Acinus - Atrophy - Nonneoplastic Lesion Atlas 294KB

https://ntp.niehs.nih.gov/atlas/nnl/reproductive-system-male/prostate/Acinus-Atrophy

Inhibitors of 5α-reductases, enzymes involved in intraprostatic conversion of testosterone to its biologically active form dihydrotestosterone, such as finasteride and ...

Seminal Vesicle, Epithelium - Hyperplasia - Nonneoplastic Lesion... 292KB

https://ntp.niehs.nih.gov/atlas/nnl/reproductive-system-male/seminal-vesicle/Epithelium-Hyperplasia

Seminal vesicle hyperplasia in rats has been reported following exposure to methylnitrosourea in the presence of either ethinyl estradiol or testosterone. In contrast to ...

TR-485: Oxymetholone (CASRN 434-07-1) in F344/N Rats and Toxicology... 12.4MB

https://ntp.niehs.nih.gov/sites/default/files/ntp/htdocs/lt_rpts/tr485.pdf

... steroid analogues of testosterone, which has complicated and divergent biological effects. ... HUMAN EXPOSURE Oxymetholone is a synthetic androgen related structurally to testosterone. ...

Epididymis - Hypospermia 878KB

https://ntp.niehs.nih.gov/sites/default/files/nnl/male_reproductive/epididymis/hypospermia/epididymis_hypospermia_508_pdf.pdf

Some toxicants can cause a decrease in transit time, thereby reducing normal sperm content (with no effect on spermatogenesis). Reduced testosterone levels will also result in ...

TR-560: Androstenedione (CASRN 63-05-8) in F344/N Rats and B6C3F1... 7.1MB

https://ntp.niehs.nih.gov/sites/default/files/ntp/htdocs/lt_rpts/tr560.pdf

... It is produced com- mercially for use as an intermediate in the synthesis of testosterone ... mones, which are known carcinogens, testosterone or estrone and ultimately to estradiol ...

Epididymis, Duct - Atrophy 914KB

https://ntp.niehs.nih.gov/sites/default/files/nnl/male_reproductive/epididymis/ductatrophy/epididymis_duct_atrophy_508_pdf.pdf

The epididymis is an androgen- dependent tissue, and atrophy can be seen in response to decreased testosterone, decreased dihydrotestosterone (e.g., 5α-reductase inhibition), or ...

Prostate, Acinus - Atrophy 831KB

https://ntp.niehs.nih.gov/sites/default/files/nnl/male_reproductive/prostate/acinatrophy/prostate_acinus_atrophy_508_pdf.pdf

Inhibitors of 5α-reductases, enzymes involved in intraprostatic conversion of testosterone to its biologically active form dihydrotestosterone, such as finasteride and ...

TOX-97: Toxicity Studies of Perfluoroalkyl Carboxylates (Perfluorohexa... 8.6MB

https://ntp.niehs.nih.gov/sites/default/files/ntp/htdocs/st_rpts/tox097_508.pdf

... No effect ↑ No effect No effect ↑ Testosterone No effect No effect No effect No ... Total Triiodothyronine No effect ↑ Testosterone ↓ ↑ Gene Expression Acox1 ↑ ↑ ...

Seminal Vesicle, Epithelium - Hyperplasia PDF 951KB

https://ntp.niehs.nih.gov/sites/default/files/nnl/male_reproductive/seminal_vesicle/epihyperpl/seminal_vesicle-epithelium-hyperplasia-pdf_508.pdf

Seminal vesicle hyperplasia in rats has been reported following exposure to methylnitrosourea in the presence of either ethinyl estradiol or testosterone. In contrast to ...

Testis, Seminiferous Tubule - Retention, Spermatid 735KB

https://ntp.niehs.nih.gov/sites/default/files/nnl/male_reproductive/testis/setubreten/testis_seminiferous_tubule_-retention_spermatid_508.pdf

Spermiation is testosterone dependant, so spermatid retention also occurs with decreased intratesticular levels of testosterone. Although subtle, this finding is important to ...

Abstract for RACB89020 61KB

https://ntp.niehs.nih.gov/publications/abstracts/repro/racb89020

hypo- or azoospermia, and elevated relative intratesticular testosterone concentration. ... Absolute and relative intratesticular testosterone concentrations were unaffected. Estrous ...

TR-547: Ethinyl Estradiol (multigenerational) (CASRN 57-63-6... 8.3MB

https://ntp.niehs.nih.gov/ntp/htdocs/lt_rpts/tr547.pdf

... a real effect, correlating well with a decrease in testosterone level and body weight. ... and decreased testicular testosterone were observed in male fetuses examined ...

TOX-96: Toxicity Studies of Perfluoroalkyl Sulfonates (Perfluorobutane... 6.0MB

https://ntp.niehs.nih.gov/sites/default/files/ntp/htdocs/st_rpts/tox096_508.pdf

... ↓ No effect ↓ ↓ No effect ↑ Testosterone No effect No effect No effect No ... chemistry, thyroid hormone, and testosterone analyses; parent compound ...

Update on NICEATM Computational Resources 6.6MB

https://ntp.niehs.nih.gov/ntp/about_ntp/sacatm/2021/ppt/2021_sacatm_s4-1_kleinstreuer_v2_508.pdf

... I I ' ' Bis(2-ethylhexyl)hexanedioate Medroxyprogesterone acetate Testosterone ... Chemic-al CASRN OTXSIO Flag Assay ..!J ..!J ..!J ..!J ..!J Testosterone 58-22-0 ...

15th RoC: Glossary 200KB

https://ntp.niehs.nih.gov/ntp/roc/content/glossary_508.pdf

... derivative of the male hormone testosterone used to promote growth and repair of ... Leydig cell a cell in the testes that secretes the hormone testosterone lipid any of the ...

CERHR Monograph: Potential Human Reproductive and Di-n-Butyl... 5.9MB

https://ntp.niehs.nih.gov/ntp/ohat/phthalates/dbp/dbp_monograph_final.pdf

... in the level of the male sex hormone, testosterone, by DBP. In a study published after ... on the male reproductive tract along with a reduction in testicular testosterone levels. ...

RoC Profile: Oxymetholone; 15th RoC 2021 136KB

https://ntp.niehs.nih.gov/ntp/roc/content/profiles/oxymetholone.pdf

Oxymetholone is a synthetic anabolic steroid that is structurally re- lated to the male hormone testosterone (IARC 1977, NTP 1999). It exists at room temperature as white-to-creamy ...

ICCVAM Test Method Evaluation Report on the BG1Luc ER TA Test... 17.5MB

https://ntp.niehs.nih.gov/iccvam/docs/endo_docs/erta-tmer/bg1lucer-ta-tmer-combined.pdf

... POS (1/1) POS (1/1) POS (1/1) Methyl testosterone 58-18-4 POS POS POS (3/3) POS (1/1) ... Compound Natural Product Methyl testosterone 58-18-4 POS POS 3.29 × 10 -6 Steroid ...

Adrenal Gland, Cortex, X-Zone - Atrophy - Nonneoplastic Lesion... 298KB

https://ntp.niehs.nih.gov/atlas/nnl/endocrine-system/adrenal-gland/CortexX-Zone-Atrophy

Administration of androgens like testosterone is followed by rapid disappearance of the X-zone in female mice. Administration of certain other chemicals can also affect the X-zone, ...

Nomination Background: p-Synephrine (CASRN: 94-07-5) 1.3MB

https://ntp.niehs.nih.gov/ntp/htdocs/chem_background/exsumpdf/bitterorange_508.pdf

... Effects on Enzymes Sour orange juice inhibited microsomal CYP3A-mediated testosterone ... D,L-Synephrine (10 µM [1.7 µg/mL]) stimulated aromatization of testosterone in Sertoli ...

Risk Assessment of Exposure to Triazole Fungicides by Human Biomonitor... 1.3MB

https://ntp.niehs.nih.gov/sites/default/files/2024-03/SOT2024-Marciano-poster.pdf

... test as a post hoc, with 5% significance. Fig. 5. Total testosterone and androstenedione. ... Serum samples . Male volunteers § Total testosterone § Androstenedione . Male volunteers ...

Response to Request for Data and Information on Zebrafish Embryo... 1.6MB

https://ntp.niehs.nih.gov/iccvam/pubcomment/fr-2016-26605/kanungo-508.pdf

... However, the testosterone level was elevated in ketamine-treated embryos. These results ... CYP aromatase; gene expression; testosterone Introduction Ketamine ...

ICCVAM Evaluation of In Vitro Test Methods for Detecting Potential... 10.6MB

https://ntp.niehs.nih.gov/iccvam/docs/endo_docs/edfinalrpt0503/edfinrpt.pdf

... data; . testosterone propionate, also proposed for in vivo testing by EPA, was excluded because it is readily hydrolyzed in vivo to its parent compound, testosterone, which has ...

TR-600: Di-n-butyl Phthalate Administered in Feed to Sprague... 3.4MB

https://ntp.niehs.nih.gov/ntp/htdocs/lt_rpts/tr600_508.pdf

... Low testosterone and decreased insulin-like peptide 3 (Insl3) levels have been observed ... fecundability. 87 Ten studies evaluated testosterone concentrations and DBP exposure. ...

Adrenal Gland, Cortex, X-Zone - Atrophy 412KB

https://ntp.niehs.nih.gov/sites/default/files/nnl/endocrine/adrenal/cxzatrophy/adrenal-gland-cortex-xzone-atrophy-pdf_508.pdf

... Administration of androgens like testosterone is followed by rapid disappearance of the X-zone in female mice. Administration of certain other chemicals can also affect the X-zone, ...

Nomination Background: Dibromoacetic acid (CASRN: 631-64-1) 266KB

https://ntp.niehs.nih.gov/ntp/htdocs/chem_background/exsumpdf/dibromoaceticacid_508.pdf

... In rats dosed with DBAA, serum testosterone fell to 17% of control2 days after a single ... form for discussions. 4 demonstrable effect on serum testosterone or sperm production. ...

NTP Monograph on Health Effects of Low-Level Lead 12.9MB

https://ntp.niehs.nih.gov/ntp/ohat/lead/final/monographhealtheffectslowlevellead_newissn_508.pdf

... status SPT skin prick test T testosterone T 3 triiodothryonine T 4 thyroxin Th-1 ... follicle-stimulating hormone (FSH), testosterone (T), and other hormones, including ...

TOX-99: A Gum Guggul Extract Formulation Administered by Gavage... 1.1MB

https://ntp.niehs.nih.gov/ntp/htdocs/st_rpts/tox99_508.pdf

... Treatment with a marketed GGE formulation decreased CYP2C9, CYP3A4-mediated testosterone ... protein (0.06 mg), midazolam (6 μM) Testosterone 6β-hydroxylase activity Potassium ...

Abstract for RACB89121 65KB

https://ntp.niehs.nih.gov/publications/abstracts/repro/racb89121

... Intratesticular testosterone. on the other hand, was reduced by over 50% at 80% and 90% BWT, compared to the ad lib controls, and reduced over 85% for the 70% BWT group. The ...

TOX-99: A Gum Guggul Extract Formulation Administered by Gavage... 1.1MB

https://ntp.niehs.nih.gov/sites/default/files/ntp/htdocs/st_rpts/tox99_508.pdf

... Treatment with a marketed GGE formulation decreased CYP2C9, CYP3A4-mediated testosterone ... protein (0.06 mg), midazolam (6 μM) Testosterone 6β-hydroxylase activity Potassium ...

RR-17: Scoping Review of Prenatal Exposure to Progestogens and... 960KB

https://ntp.niehs.nih.gov/sites/default/files/ntp/results/pubs/rr/reports/rr17_508.pdf

... called synthetic progestins) are structurally related to progesterone and testosterone. ... male animals consistent with inhibited testosterone (e.g., presence of a vaginal anlage, ...

Research Concept for Perfluorinated Compounds Class ; July 8... 78KB

https://ntp.niehs.nih.gov/ntp/noms/final_resconcept/pfoaconcept_508.pdf

... hematology, clinical chemistry (serum triglycerides, cholesterol, estradiol, testosterone, thyroid hormones, alkaline phosphatase, bile acids, globulin), SMVCE, and terminal ...

Abstract for TOX-99 69KB

https://ntp.niehs.nih.gov/publications/reports/tox/000s/tox099

... Treatment with a marketed GGE formulation decreased CYP2C9, CYP3A4-mediated testosterone 6β-hydroxylase, and CYP2C19 metabolic activity in human microsomal preparations. ...

Comment: Toxicology and Carcinogenesis Studies of Sodium Tungstate... 143KB

https://ntp.niehs.nih.gov/ntp/about_ntp/trpanel/2021/april/publiccomm/lemus20210318_trprp_508.pdf

... the appearance of number of Leydig cells, or change the serum levels of luteinizing hormone (LH), follicle-stimulating hormone (FSH) and testosterone (Ballester et al., 2005). ...