http://magazine.mindandmuscle.net/magmain.php?issueID=6&pageID=72
2nd paragraph in the conclusion from Bills study, incase there is any doubt.
Nolvadex would seem to provide a better and more stable increase in testosterone levels
Why are you being an asshole about this? And no, I'm not spouting "bro-telligence" at you. I get tested during EVERY PCT, and I can tell you with fact I was below baseline after 4 weeks of Nolva, but above baseline after 4 weeks of Clomid from two different cycles of THE SAME COMPOUNDS.
As for studies...
Credit to Blown_SC at ironforlife for these:
Tamox vs Clomid
Am J Physiol 1983 Feb;240(2):E125-30
Disparate effect of clomiphene and
tamoxifen on pituitary gonadotropin release in vitro.
Adashi EY, Hsueh AJ, Bambino TH, Yen SS.
The direct effects of clomiphene citrate (Clomid),
tamoxifen, and estradiol (E2) on the gonadotropin-releasing hormone (GnRH)-stimulated release of luteinizing hormone (LH) and follicle-stimulating hormone (FSH) were studied in cultured anterior pituitary cells obtained from adult ovariectomized rats. Treatment of pituitary cells with
Clomid or enclomid (10(-8) M) in vitro for 2 days resulted in a marked sensitization of the gonadotroph to GnRH as reflected by a 6.5-fold decrease in the ED50 of GnRH in terms of LH release from 2.2 x 10(-9) M in untreated cells to 3.6 x 10(-10) M. Treatment with E2 or
Clomid also increased the sensitivity of the gonadotroph to GnRH in terms of FSH release by 4.3- and 3.3-fold respectively.
Tamoxifen, a related antiestrogen, comparable to
Clomid in terms of its ability to compete with E2 for pituitary
estrogen receptors, was without effect on the GnRH-stimulated LH release at a concentration of 10(-7) M. Furthermore,
tamoxifen, unlike
Clomid, caused an apparent but not statistically significant inhibition of the sensitizing effect of E2 on the GnRH-stimulated release of LH. Our findings suggest that
Clomid and its Enclomid isomer, unlike
tamoxifen, exert a direct estrogenic rather than an antiestrogenic effect on cultured pituitary cells by enhancing the GnRH-stimulated release of gonadotropin.
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Br J Pharmacol 1978 Apr;62(4):487-93
Differential depletion of cytoplasmic high affinity oestrogen receptors after the in vivo administration of the antioestrogens, clomiphene, MER-25 and
tamoxifen.
Kurl RN, Morris ID.
1 The in vivo actions of the oestrogen antagonists, MER-25 and
tamoxifen upon the cytosol oestrogen receptors prepared from amygdala, hypothalamus, pituitary and uterus of rats were studied 24 h after drug administration. 2 There was a dose-related depletion of cytosol oestrogen receptors. However, the uterine and pituitary receptors were consistently affected at a lower dose than were those from the brain. 3 The ratios of the combined central ED50 to the combined peripheral ED50 were clomiphene 169 greater than MER-25 19.2 greater than
tamoxifen 2.13. 4 The receptor changes were not related to biological activity monitored by serum luteinizing hormone levels and uterotrophic response. 5 The possible role of these drug effects in the induction of ovulation and future developments are discussed.
Case for Clomid
J Clin Endocrinol Metab 1985 Nov;61(5):842-5
Evidence for a role of endogenous
estrogen in the hypothalamic control of gonadotropin secretion in men.
Winters SJ, Troen P.
To examine the mechanism by which endogenous
estrogens inhibit gonadotropin secretion in men, blood samples were drawn every 10 min for 12 h in five men before and at the completion of 3 weeks of treatment with the
estrogen antagonist clomiphene citrate (50 mg twice daily). Samples were analyzed for LH and alpha-subunit by RIA. Clomiphene produced a 3-fold rise in circulating LH levels, which was associated with a 80% increase in pulse frequency and a 70% increase in pulse amplitude. Immunoreactive alpha-subunit secretion was also pulsatile before and after clomiphene treatment. Mean alpha-levels rose 70%, together with a 39% increase in pulse frequency and a 41% increase in pulse amplitude. Circulating testosterone and estradiol levels increased 2-fold and FSH levels increased 3-fold after clomiphene treatment. Insofar as each LH and uncombined alpha-subunit pulse reflects a LHRH secretory episode, our data indicate that endogenous
estrogens tonically restrain the hypothalamic release of LHRH. From these results and those of previous studies, we conclude that
estrogens as well as androgens are important in the testicular feedback inhibition of the hypothalamic oscillator that governs pulsatile gonadotropin secretion.
J Androl 1991 Jul-Aug;12(4):258-63
The effects of normal aging on the response of the pituitary-gonadal axis to chronic clomiphene administration in men.
Tenover JS, Bremner WJ.
Department of Medicine, University of Washington School of Medicine, Seattle.
Serum androgens decline with age in normal men, despite normal or elevated bioactive serum gonadotropins, suggesting that primary testicular dysfunction occurs with aging. The authors further assessed the question of age-related testicular dysfunction by evaluating whether raising serum gonadotropins above the normal serum range for an extended time in healthy elderly men might result in bringing their gonadal function to a level similar to that found in young adult men. Five elderly (65 to 85 years old) and five young adult men (26 to 33 years old) were given 50 mg of clomiphene citrate (CC) twice a day for 8 weeks to stimulate gonadotropin production. During that time, testosterone (T), non-sex hormone-binding globulin bound T, and estradiol increased significantly in both age groups, while serum inhibin increased significantly only in the young adult men. The increases in serum androgens with CC administration were significantly greater in the young adult men than in the elderly men. These hormone changes occurred in the setting of serum gonadotropins that increased significantly in both age groups, although there was a tendency for the elderly men to have a smaller increase in luteinizing hormone. Despite 8 weeks of stimulation of the pituitary-gonadal axis by CC administration, the elderly men demonstrated significantly diminished testicular responses compared with the young adult men. Sertoli cell function, as determined by inhibin production, was more diminished in the elderly men than was Leydig cell function. These data strengthen the hypothesis that normal aging in men is accompanied by a decline in testicular function.
Urology 1991 Oct;38(4):317-22
Possible hypothalamic impotence. Male counterpart to hypothalamic amenorrhea?
Guay AT, Bansal S, Hodge MB.
Section of Endocrinology, Lahey Clinic Medical Center, Burlington, Massachusetts.
Twenty-one men with erectile complaints who were found to have a low level of serum testosterone without a reciprocal elevation of the serum levels of luteinizing hormone were evaluated to identify whether the defect was of hypothalamic or of pituitary origin. Patients underwent a luteinizing hormone (LH)-follicle-stimulating hormone (FSH)-releasing hormone stimulation test that showed a normal but sluggish increase in LH and FSH levels, thus ruling out a pituitary defect and suggesting a suprapituitary abnormality. This was confirmed when, in response to clomiphene, patients had a normal increase in gonadotropin and testosterone levels. Although the basal as well as clomiphene and gonadotropin releasing hormone-stimulated levels of total testosterone and gonadotropins were identical in men less than and more than fifty years old, the elevation of free testosterone levels in response to clomiphene was higher in patients younger than fifty. This suggested that although the primary abnormality found in these patients is altered secretion of gonadotropin hormone-releasing hormone from the hypothalamus, an age-related decline in the responsivity of Leydig cells to LH may make it more manifest in older patients. Elevation of testosterone levels from a subnormal to a normal range in response to clomiphene administered for seven days suggests that the defect is functional and reversible and that the drug may be useful in treatment of sexual dysfunction in this group of patients.
Nephron 1993;63(4):390-4
Effect of clomiphene citrate on hormonal profile in male hemodialysis and kidney transplant patients.
Martin-Malo A, Benito P, Castillo D, Espinosa M, Burdiel LG, Perez R, Aljama P.
Department of Nephrology, Hospital Universitario Reina Sofia, Cordoba, Spain.
The aim of this study was to evaluate the role of clomiphene citrate (CC) therapy in the hypothalamus-pituitary-gonadal axis of male uremic subjects. Thirty-four patients on hemodialysis (HD) and 8 successful kidney transplant subjects (RT) were evaluated. Nine healthy males were used as controls (C). At baseline, zinc, testosterone (TEST), prolactin (PRL), FSH, LH and estradiol plasma concentrations were measured. All subjects were treated with CC (100 mg/day) for a week. The aforementioned parameters were determined again on the seventh day of CC therapy, and 3 days after drug withdrawal. Following CC, there was a rise in FSH, LH and TEST levels in all subjects (p < 0.05); it is interesting to stress that TEST became normal in HD. In addition, we observed a decrease of PRL after CC only in HD patients (p < 0.01). In summary, CC was able to partially correct most of the hormonal disturbances of the gonadal axis in uremic patients.
Tamoxifen
nolvadex aka
tamoxifen studies:
Arch Gynecol Obstet 1993;252(3):143-7
Tamoxifen treatment of oligozoospermia: a re-evaluation of its effects including additional sperm function tests.
Sterzik K, Rosenbusch B, Mogck J, Heyden M, Lichtenberger K.
Abteilung Frauenheilkunde, Geburtshilfe der Universitat, Ulm, Germany.
Because of previous contradictory results, we reevaluated the effects of
tamoxifen on 29 men presenting with idiopathic oligozoospermia. To determine whether a possible increase in sperm concentration might be correlated with an improvement of sperm quality, the hamster ovum penetration (HOP) test and the hypo-osmotic swelling (HOS) test were included as additional tests of sperm function. Patients were treated with
tamoxifen (20 mg/day) for 3 months. From 4 weeks until the end of the study,
tamoxifen had no significant effect (P > 0.05) on blood levels of luteinizing hormone (LH), follicle-stimulating hormone (FSH), testosterone (T), or estradiol (E2). There was no significant improvement (P > 0.05) of conventional semen parameters (volume, concentration, motility, morphology), and of HOP and HOS test results. The lack of correlation between a rise in hormone levels and improvement of sperm quality suggests that
tamoxifen is of questionable value in men with idiopathic oligozoospermia.
Asian J Androl 2001 Jun;3(2):115-9
Effect of intermittent treatment with
tamoxifen on reproduction in male rats.
Gill-Sharma MK, Balasinor N, Parte P.
Department of Neuroendocrinology, Institute for Research in Reproduction, ICMR, Parel, Mumbai, India.
[email protected]
AIM: To identify the antifertility effect of intermittent oral administration of
tamoxifen in male rat. METHODS:
Tamoxifen was administered orally at a dose of 0.4 mg x kg(-1) x d(-1) with an intermittent regime for 120 days. Treated and control rats were mated with cycling female rats on days 60, 90 and 120 of treatment. The mated males were sacrificed and the weights of reproductive organs were recorded, and the serum levels of LH, FSH, testosterone and estradiol estimated by radioimmunoassay. In the female rats, the numbers of implantation sites, corpora lutea, and numbers of normal and resorbed foetuses were recorded on d 21 of gestation. The potency, fecundity, fertility index, litter size and post-implantation loss were then calculated. RESULTS: The fecundity of male rats was completely suppressed by
tamoxifen while the potency was maintained at the control level. The fertility index was significantly decreased. No viable litters were sired. Post implantation loss, indicative of non-viable embryos, was observed but was not significantly increased above the control level. The weights of the testes, epididymides, ventral prostate and seminal vesicles were significantly reduced. The blood LH and testosterone levels were significantly decreased, but not FSH and estradiol. CONCLUSION: Intermittent oral
tamoxifen administration completely suppressed the fecundity of adult male rats with reserved potency.
Case study showing benefit to FSH, LH, and testosterone from tamox- Notice administration duration
Treatment of idiopathic and post varicocelectomy oligozoospermia with oral
tamoxifen citrate.
BJU Int 1999 Apr; 83: 646-8
Kadioglu TC Köksal IT Tunç M Nane I Tellaloglu S
[see related articles]
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Affiliation
Department of Urology, Faculty of Medicine, Istanbul University, Istanbul, Turkey.
Abstract
OBJECTIVE: To identify a subgroup of men who may benefit from
tamoxifen citrate (a widely prescribed drug for male infertility) among those with normogonadotrophic and hypergonadotrophic oligozoospermia, either idiopathic or after varicocelectomy. PATIENTS AND METHODS: The study included infertile men with oligozoospermia, 136 referred to our outpatient clinic and 84 infertile after varicocelectomy. All patients received
tamoxifen citrate (10 mg twice daily); semen analysis and hormone tests were repeated at the end of 3 and 6 months of treatment, the values being compared with those before treatment. RESULTS : The levels of follicle-stimulating hormone, luteinizing hormone and testosterone increased in all groups receiving
tamoxifen citrate. Normogonadotrophic patients had a significant increase in sperm count and concentration, while the slight increase detected in the hypergonadotrophic group was statistically insignificant. CONCLUSION: In patients with normogonadotrophic oligozoospermia,
tamoxifen citrate may be offered as a practical and economic alternative before using any assisted reproduction techniques. However, double-blind placebo-controlled trials are needed to confirm the findings of this preliminary study.