D-Aspartic acid (D-Asp) and nitric oxide (NO) are two biologically active molecules playing important functions as neurotransmitters and neuromodulators of nerve impulse and as regulators of hormone production by endocrine organs. We studied the occurrence of D-Asp and NO as well as their effects on testosterone synthesis in the testis of boar. This model was chosen for our investigations because it contains more Leydig cells than other mammals. Indirect immunofluorescence applied to cryostat sections was used to evaluate the co-localization of D-Asp and of the enzyme nitric oxide synthase (NOS) in the same Leydig cells. D-Asp and NOS often co-existed in the same Leydig cells and were found, separately, in many other testicular cytotypes. D-Asp level was dosed by an enzymatic method performed on boar testis extracts and was 40+/- nmol/g of fresh tissue. NO measurement was carried out using a biochemical method by NOS activity determination and expressed as quantity of nitrites produced: it was +/- nmol/mg of tissue. The effects of the two molecules on steroid hormone production were evaluated by incubating testis homogenates, respectively with or without D-Asp and/or the NO-donor L-arginine (L-Arg). After incubation, the testosterone presence was measured by immunoenzymatic assay (EIA). These in vitro experiments showed that the addition of D-Asp to incubated testicular homogenates significantly increased testosterone concentration, whereas the addition of L-Arg decreased the hormone production. Moreover, the inclusion of L-Arg to an incubation medium of testicular homogenates with added D-Asp, completely inhibited the stimulating effects of this enantiomer. Our results suggest an autocrine action of both D-Asp and NO on the steroidogenetic activity of the Leydig cell.
Yes, yes, we all know this. It works. Tried it myself and I believe that short cycles are the way forward. BUT, we have enough questions from newbies on here about their mostly clueless PCT plans. I don't think that we need someone coming along on a board like this one saying 'look kids, I did a 6 weeks cycle, and used almost no PCT and I'm fine'. On a board like this one, that (to me) sends out the wrong message. Gregus perhaps has the experience to accurately assess what works for him. How many of the newbies that we hear from time and time again, would you feel confident saying the same thing about....?
I completely agree with you, Kyle. Whenever exogenous Testosterone is stopped – whether it was being taken for TRT or cycled for bodybuilding – some kind of ‘PCT’ (Post-Cycle Therapy) should be utilized to help ‘re-awaken’ your HPG axis after it had been shut down by Testosterone replacement or cycling. It is important to note that such PCT is NOT taken forever! The use of HCG and either Tamoxifen or Clomid will help greatly in reducing withdrawal symptoms by bolstering your body’s natural Testosterone production and greatly speeding up recovery time (the time it takes for your body to start creating its own testosterone again without any external substance).