HCG desensitization DOES NOT occur clinically. Anyone who says it does, does not know the literature, is trying to advance a myth, and probably believes in the hCG diet! Can hCG desensitization occur? Absolutely. There are many animal models demonstrating this effect, but, again, this effect is NOT seen clinically in FDA approved doses or less. Is there evidence for hCG desensitization in humans for hCG doses higher than FDA approved levels? Indirectly, a single (just one thats why you couldnt post any back up to your claim) study in does over 5,000 IU exploring testicular response to hCG administration reveals a leveling of T production.
hCG administration does stimulate estradiol and progesterone production. In fact, the estradiol rise occurs before the T rise.
The article "van Bergeijk L, Gooren LJ, van der Veen EA, de Vries CP. Effects of short- and long-term administration of tamoxifen on hCG-induced testicular steroidogenesis in man: no evidence for an oestradiol-induced steroidogenic lesion. Int J Androl 1985;8(1):28-36,: cited as support does nothing of the sort. This is a vain attempt to confuse the issue and by hopefully presenting a peer-reviewed article to win the argument. It ain't gonna work!
According to the abstract, the study examines the effect of tamoxifen hCG-induced testicular steroidogenesis. They do not use a model of hCG desensitization. The study is exploring a "local" effect of estradiol on T production. In fact, if you even give the slightest thought the study is about hCG desensitization, the study would not work!!! Duh . . . If the cells were desensitized to hCG, they would not produce estradiol or T, thus NO study on tamoxifen effects.
Another study (abstract below) cited by another forum is "Tang P-Z, Tsai-Morris CH, Dufau ML. Regulation of 3{beta}-Hydroxysteroid Dehydrogenase in Gonadotropin-Induced Steroidogenic Desensitization of Leydig Cells. Endocrinology 1998;139(11):4496-505." THIS IS A STUDY IN RATS!!! This expert is so desperate to prove him/herself. they cite rat studies. If we were to translate this study to humans, which is fraught with so many pitfalls, the easiest method is by dose (IU/kg). The dose for the rats is 100-125 IU/kg. For a 75 kg human, this would be 7,500 IU or more. A dose more than FDA approved, used clinically, and what they claim to cause hCG desensitization.
3{beta}-hydroxysteroid dehydrogenase/{Delta}5-{Delta}4 isomerases (3{beta}-HSD) are enzymes that catalyze the conversion of {Delta}5 to {Delta}4 steroids in the gonads and adrenal for the biosynthesis of sex steroid and corticoids. In gonadotropin-desensitized Leydig cells, from rats treated with high doses of human CG (hCG), testosterone production is markedly reduced, a finding that was attributed in part to reduction of CYP17 expression. In this study, we present evidence for an additional steroidogenic lesion induced by gonadotropin. Using differential display analysis of messenger RNA (mRNA) from Leydig cells of rats treated with a single desensitizing dose of hCG (2.5 {micro}g), we found that transcripts for type I and type II 3{beta}-HSD were substantially (5- to 8-fold) down-regulated. This major reduction, confirmed by RNase protection assay, was observed at the high hCG dose (2.5 {micro}g), whereas minor or no change was found at lower doses (0.01 and 0.1 {micro}g). In contrast, 3{beta}-HSD mRNA transcripts were not changed in luteinized ovaries of pseudopregnant rats treated with 2.5 {micro}g hCG. The down-regulation of 3{beta}-HSD mRNA in the Leydig cell resulted from changes at the transcriptional level. Western blot analysis showed 3{beta}-HSD protein was significantly reduced by hCG treatment, with changes that were coincidental with the reduction of enzyme activity and temporally consistent with the reduction of 3{beta}-HSD mRNA but independent of LH receptor down-regulation. The reduction of 3{beta}-HSD mRNA resulting from transcriptional inhibition of gene expression, and the consequent reduction of 3{beta}-HSD activity could contribute to the inhibition of androgen production in gonadotropin-induced steroidogenic desensitization of Leydig cells. The gender-specific regulation of 3{beta}-HSD by hCG reflects differential transcriptional regulation of the enzymes to accommodate physiological hormonal requirements and reproductive function
In case the readers did not notice this is the same study PP is referencing in its atricle to back up its "desensitization theory".......................