The changes of the thyroid function and serum testosterone levels after long-term L-NAME treatment in male rats

1998 ◽  
Vol 21 (4) ◽  
pp. 234-238 ◽  
Author(s):  
M. Haluzík ◽  
J. Nedvídková ◽  
V. Kopský ◽  
J. Jahodová ◽  
B. Hořejší ◽  
...  
Keyword(s):  
Thyroid Function ◽  
Serum Testosterone ◽  
Male Rats ◽  
Testosterone Levels

Short- and long-term effects of testosterone on diaphragm in castrated and normal male rats

1997 ◽  
Vol 82 (1) ◽  
pp. 134-143 ◽  
Author(s):  
David J. Prezant ◽  
Manoj L. Karwa ◽  
Helen H. Kim ◽  
Diane Maggiore ◽  
Virginia Chung ◽  
...  
Keyword(s):  
Serum Testosterone ◽  
Male Rats ◽  
Normal Male ◽  
Type Ii ◽  
Long Term Effects ◽  
Testosterone Levels ◽  
Diaphragm Function ◽  
Short And Long Term ◽  
Normal Males

Prezant, David J., Manoj L. Karwa, Helen H. Kim, Diane Maggiore, Virginia Chung, and David E. Valentine. Short- and long-term effects of testosterone on diaphragm in castrated and normal male rats. J. Appl. Physiol. 82(1): 134–143, 1997.—The effects of short- and long-term testosterone absence or treatment on the diaphragm were studied in castrated and sexually normal male rats. Compared with control rats (untreated normal males), testosterone absence or treatment did not significantly affect costal weight. In untreated castrated males, there were significant decreases in specific forces, type II fiber cross-sectional area, and myosin heavy chain (MHC) isoform 2B after 2.5 wk. In castrated males that received testosterone, there were significant increases in specific forces, type II total fiber proportional area, and relative expression of all adult diaphragm fast MHC isoforms (MHC-2all) after 2.5 wk. In normal males that received testosterone, the only significant finding was an increase in MHC-2B after 2.5 wk. Across all groups, there was close correlation between increases in maximum tetanic forces and MHC-2all. Changes in diaphragm function and composition were closely related to changes in serum testosterone levels at 2.5 wk. The lack of significant change in diaphragm function at 10 wk occurred despite changes in serum testosterone levels and diaphragm composition similar to those at 2.5 wk. These findings support our hypothesis that the effects of testosterone are dependent on basal circulating androgen levels and study duration.

scholarly journals Decreased Serum Testosterone Levels in Long-Term Adult Survivors with Fatty Liver after Childhood Stem Cell Transplantation

2012 ◽  
Vol 18 (7) ◽  
pp. 1119-1127 ◽  
Author(s):  
Hiromi Hyodo ◽  
Hiroyuki Ishiguro ◽  
Yuichiro Tomita ◽  
Hiromitsu Takakura ◽  
Takashi Koike ◽  
...  
Keyword(s):  
Stem Cell ◽  
Stem Cell Transplantation ◽  
Fatty Liver ◽  
Cell Transplantation ◽  
Serum Testosterone ◽  
Adult Survivors ◽  
Testosterone Levels

scholarly journals The Production of Testosterone and Gene Expression in Neonatal Testes of Rats Exposed to Diisoheptyl Phthalate During Pregnancy is Inhibited

2021 ◽  
Vol 12 ◽  
Author(s):  
Bin Ji ◽  
Zina Wen ◽  
Chaobo Ni ◽  
Qiqi Zhu ◽  
Yiyan Wang ◽  
...  
Keyword(s):  
Leydig Cell ◽  
Corn Oil ◽  
Serum Testosterone ◽  
Male Rats ◽  
Sprague Dawley ◽  
Testosterone Levels ◽  
Protein Levels ◽  
Gestational Exposure ◽  
Phthalate Plasticizer ◽  
Neonatal Testis

Background: Diisoheptyl phthalate (DIHP) is a phthalate plasticizer, which is a branched phthalate. Here, we reported the effects of gestational exposure to DIHP on testis development in male rats.Methods: Pregnant Sprague-Dawley rats were orally fed with vehicle (corn oil, control) or DIHP (10, 100, 500, and 1,000 mg/kg) from gestational day (GD) 12–21. At GD21, serum testosterone levels, the number and distribution of fetal Leydig cells, and testicular mRNA and protein levels, the incidence of multinucleated gonocytes, and focal testicular hypoplasia in the neonatal testis were measured.Results: DIHP increased the fetal Leydig cell cluster size and decreased the fetal Leydig cell size with LOAEL of 10 mg/kg. DIHP did not affect the fetal Leydig cell number. DIHP significantly lowered serum testosterone levels, down-regulated the expression of steroidogenesis-related genes (Lhcgr, Star, Cyp11a1, Hsd3b1, Cyp17a1, and Hsd17b3) and testis descent-related gene (Insl3) as well as protein levels of cholesterol side-chain cleavage enzyme (CYP11A1) and insulin-like 3 (INSL3). DIHP dose-dependently increased the percentage of multinucleated gonocytes with the low observed adverse-effect level (LOAEL) of 100 mg/kg. DIHP induced focal testicular hypoplasia.Conclusion: Gestational exposure to DIHP causes testis dysgenesis in rats.

scholarly journals Evaluation of The Effect of Pasak Bumi (Eurycoma longifolia Jack) to Increase Androgen Levels

INSIST ◽  
2016 ◽  
Vol 1 (1) ◽  
Author(s):  
Hurip Pratomo
Keyword(s):  
Serum Testosterone ◽  
Female Rats ◽  
Male Rats ◽  
Male Rat ◽  
Testosterone Levels ◽  
Eurycoma Longifolia ◽  
Testosterone Administration ◽  
Eurycoma Longifolia Jack ◽  
Boiled Water ◽  
Androgen Levels

Abstract—Background:The ability of reproductive disorders in men and experimental male rat is characterized among other things by a decrease in androgen such as testosterone levels. Materials of pasak bumi root (Eurycoma longifolia Jack) increased libido behavior of experimental male rat. Libido associated with higher levels of testosterone, it is therefore necessary to evaluate the effect of pasak bumi on androgen levels such as testosterone. Methods: Male rats at 9.00 am treated controls and pasak bumi, then at 14.00 pm tempted with estrus female rats 10 minutes. Then, both control and pasak bumi blood  samples were collected from male rat heart on day 1st  and day 3rd  at 14.15 pm. Measurement of testosterone levels were calculated using radioimmunoassay (RIA). Results: An increase in serum  testosterone levels in the blood on day-3rd  administration pasak bumi boiled water 18 mg/200 g dose  significantly different than the  control within day 1st to 3rd. The average levels of testosterone administration control (boiled water of aquades) day 1st = 0.50 ng/ml, day 3rd = 2.46 ng / ml, increased markedly on pasak bumi treatment day 1st = 4.00 ng / ml and day 3 = 9.73 ng / ml, (Duncan test, α=0.05). Conclusions: Testosterone levels can be increased markedly after the consumption of the pasak bumi boiled water for 3 days.Keywords—Pasak bumi, a dose of  18 mg/200 g, testosterone.

LONG-TERM EFFECT OF CYPROTERONE ON TESTOSTERONE LEVELS IN MALE RATS

1973 ◽  
Vol 71 (4_Suppl) ◽  
pp. S119 ◽  
Author(s):  
S. H. Hasan ◽  
F. Neumann ◽  
B. Schenck
Keyword(s):  
Term Effect ◽  
Male Rats ◽  
Testosterone Levels ◽  
Long Term Effect

scholarly journals Breast Tissues in Transsexual Women–A Nonprostatic Source of Androgen Up-Regulated Production of Prostate-Specific Antigen

1999 ◽  
Vol 84 (9) ◽  
pp. 3313-3315
Author(s):  
Victor H. H. Goh
Keyword(s):  
Prostate Specific Antigen ◽  
Specific Antigen ◽  
Serum Testosterone ◽  
Serum Levels ◽  
Androgen Therapy ◽  
Testosterone Levels ◽  
The Mean ◽  
Breast Tissues ◽  
Serial Measurements

The present study made use of the female transsexual model and sought to evaluate the contributions of the ovarian, endometrial, and breast tissues to the androgen up-regulated production of prostate specific antigen (PSA). Serum levels of PSA were significantly raised in female transsexuals before surgery, after long-term androgen therapy (mean ± se = 35.3 ± 6.2 pg/mL) when compared with female transsexuals before surgery, but with no androgen therapy (mean ± se = 1.53 ± 0.25 pg/mL). In addition, in androngenized female transsexuals, after surgery, concentrations of PSA (mean ± se = 14.5 ± 2.8 pg/mL) were significantly lowered compared with androngenized female transsexuals after surgery, but the levels were, nevertheless, significantly higher than in normal females. Monthly im injection of 250 mg Sustanon-250 to female transsexuals had raised serum testosterone levels to within the male range. In five subjects, in whom serial measurements were taken, serum testosterone levels were greatly raised 24 h after the testosterone therapy; the mean level (±se) was 19.5 ± 2.1 ng/mL. But in spite of these high testosterone levels, serum PSA levels (mean ± se= 2.2 ± 0.9 pg/mL) were not significantly raised. However, after 12 months of androgen therapy, the mean (±se) PSA level in these five subjects was 47 ± 11.6 pg/mL and was significantly higher than the mean level in nonandrogenized female transsexuals. The present study confirmed that high levels of testosterone were able to up-regulate PSA production in women. This up-regulation of PSA production is both a dose- and time-dependent process. Furthermore, the evidence indicates that breast tissues are possibly a nonprostatic source of androgen up-regulated production of PSA women.

Injectable testosterone undecanoate has more favourable pharmacokinetics and pharmacodynamics than testosterone enanthate

1995 ◽  
Vol 132 (4) ◽  
pp. 514-519 ◽  
Author(s):  
Carl-Joachim Partsch ◽  
Gerhard F Weinbauer ◽  
Ruiying Fang ◽  
Eberhard Nieschlag
Keyword(s):  
Body Weight ◽  
Serum Testosterone ◽  
Pharmacokinetic Analysis ◽  
Male Hypogonadism ◽  
Androgen Deficiency ◽  
Testosterone Enanthate ◽  
Pharmacokinetics And Pharmacodynamics ◽  
Testosterone Undecanoate ◽  
Testosterone Levels

Partsch C-J, Weinbauer GF, Fang R, Nieschlag E. Injectable testosterone undecanoate has more favourable pharmacokinetics and pharmacodynamics than testosterone enanthate. Eur J Endocrinol 1995;132:514–19. ISSN 0804–4643 Testosterone preparations producing constant physiological testosterone serum levels are desirable for long-term treatment of androgen deficiency. However, all injectable testosterone esters used clinically for substitution of male hypogonadism are characterized by unfavourable pharmacokinetics. We therefore tested two groups of five long-term orchidectomized cynomolgus monkeys (Macaca fascicularis), which received a single intramuscular injection of 10 mg/kg body weight of an injectable testosterone undecanoate (TU) preparation or testosterone enanthate (TE) in a preclinical study to assess the pharmacokinetic and pharmacodynamic characteristics of TU in comparison to TE. The dose was equivalent to 6.3 and 7.2 mg of pure testosterone per kilogram body weight in the TU and TE group, respectively. Following injection of TU, mean serum testosterone rose to 58 ± 18 nmol/l on day 1 and remained at moderately supraphysiological levels of 40–68 nmol/l for 45 days. Thereafter, testosterone levels were maintained in the normal range of intact monkeys for another 56 days. The TE injection resulted in highly supraphysiological levels of 100–177 nmol/l from immediately after the injection to day 5. A rapid decline followed and testosterone levels reached the lower limit of normal after 31 days. Serum testosterone levels were significantly higher in the TEthan in the TU-treated animals on days 0.5–7 (p < 0.05). Significantly lower testosterone levels were seen in the TE than in the TU group on days 16, 22, 25 and 31 (p < 0.05). Pharmacokinetic analysis of serum testosterone levels showed a significantly higher area under the curve for TU (4051 ± 939 vs 1771 ±208 nmol·h/l; p < 0.045), a longer residence time (40.7 ±4.1 vs 11.6 ±1.1 days; p <0.00012), a longer terminal half-life (25.7 ± 4.0 vs 10.3 ± 1.1 days; p < 0.0069), and a lower maximal testosterone concentration (73 ± 12 vs 177 ± 21 nmol/l; p < 0.0027). Following TU injection, oestradiol levels increased from 48 ± 8 pmol.l to a plateau of 80–118 pmol/l from day 1 to day 59. In contrast, TE injection resulted in a rapid increase of oestradiol levels to a maximum of 166 ± 29 pmol/l after 4 days (p < 0.05 vs TU- treated group). In the TU and TE groups levels below 80 pmol/l were reached after 66 and 16 days, respectively. Ejaculatory response was induced for 14 weeks in the TU animals in contrast to 7 weeks in the TE animals. Ejaculate weight reached a maximum of 533 ± 163 mg at day 52 in the TU group (p < 0.05 vs TE group). In the TE animals, the maximal ejaculate weight of 41 ± 17 mg was seen at day 16. Thus, with respect to androgen substitution therapy, TU showed pharmacokinetic and pharmacodynamic properties clearly superior to those of TE and may provide an important improvement in the substitution of male androgen deficiency and also for male contraception. E Nieschlag, Institute of Reproductive Medicine of the University, Steinfurter Str. 107, D-48149 Münster, Germany

Effect of goitrogen administration on the circadian rhythm of serum thyroid stimulating hormone in the rat

1981 ◽  
Vol 98 (3) ◽  
pp. 396-401 ◽  
Author(s):  
B. Stringer ◽  
D. Wynford-Thomas ◽  
B. Jasani ◽  
E. D. Williams
Keyword(s):  
Circadian Rhythm ◽  
Thyroid Hormone ◽  
Circadian Rhythms ◽  
Thyroid Function ◽  
Diurnal Rhythm ◽  
Thyroid Stimulating Hormone ◽  
Male Rats ◽  
Hormone Synthesis ◽  
Serum Tsh

Abstract. Adult male rats were fed a goitrogen, aminotriazole, for 74 days at a dose known to suppress thyroid function completely. At the end of this period, these animals along with matched controls were killed in groups of seven at 3 hourly intervals throughout a 24 hour period, and serum TSH, T3, T4 and albumin assayed. No significant circadian rhythms of T3, T4 or albumin were found in either, but a highly significant rhythm of TSH was demonstrated both in controls and goitrogen treated groups, with a diminished relative amplitude in the latter. The results indicate that a significant diurnal rhythm of serum TSH persists in the rat despite long-term blockade of thyroid hormone synthesis and that the existence of this rhythm is therefore independent of the presence of circulating T3 or T4.

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