DavidZ said:
The large initial dosages (about 2,500 IU/week for 2 or 3 weeks) is a stimulation test. These dosages are necessary, particularly with older men, because initial leydig cell response is often weak. It takes some time for leydig cell response to return to full capacity. The HCG shot dosage is then adjusted based on subsequent blood tests and clinical response.
Skipping days between HCG shots is the way to go.
There's a common misconception that HCG shuts down the h/p axis. While the increase in T that results from HCG does shut down the h/p axis as you would expect, HCG itself actually stimulates the h/p axis.
When a man is "responsive" to HCG, the response occurs in 2 ways - the testicles and the h/p axis. Medline article 4044781 documents HCG's "self-priming" effect on the h/p axis. This article indicates that an initial peak in T occurs 2 to 8 hours after an HCG shot and a second peak in T occurs 48 to 72 hours after the shot. The second peak is caused by LH production. In other words, HCG primes the pump (the h/p axis).
Stimulates how? Production of GRH? Some of his protcols started again this misconception that guys can "bridge" between cycles with hCG. We all know now, there is no such thing as a bridge.
I dont see how hCG can stimulate GRH, leading to LH production? Can you please show us how this happens? Or does it stimulate the HP directly?
David I only see the abstract on the net, if you have it, can you post it to this board entirely, I would like to look at it more closely. I wonder if this had to do with its pharmokinetics.
Swale, what are your thoughts to that study?
David here is something else that I found:
Prolonged biphasic response of plasma testosterone to single intramuscular injections of human chorionic gonadotropin.
Padron RS, Wischusen J, Hudson B, Burger HG, de Kretser DM.
The response of plasma testosterone to varying doses of hCG (0--6000 IU) given as a single im injection has been evaluated in normal men.
After an initial rise at 2 h, the levels of testosterone demonstrated a secondary rise, reaching a peak 48 h after the im injection. The magnitude of the response varied directly with the dose of hCG used, and at the highest dose (6000 IU) testosterone levels were still elevated 6 days after administration. Plasma estradiol levels showed a dose-dependent rise, with peak levels being attained 24 h after hCG. The prolonged response of plasma testosterone to a single injection of hCG should prompt a reevaluation of diagnostic and therapeutic regimens using this agent.
PMID: 7372789 [PubMed - indexed for MEDLINE]
AND
Testicular responsiveness to a single hCG dose in patients with testicular feminization.
Balducci R, Adamo MV, Mangiantini A, Municchi G, Toscano V.
Clinica Pediatrica 2nd University, La Sapienza, Rome, Italy.
The suggestion that androgens may regulate testosterone (T) production in rat Leydig cells by a receptor-mediated feed-back mechanism, led us to investigate whether in vivo the absence of testicular androgen receptors, as it occurs in testicular feminization (TF), may modify the characteristic testicular response observed in men and prepubertal children after a single dose of hCG. Subjects consist of: 1) six normal men, 2) two adult patients with the complete form of androgen insensitivity syndrome (TF), 3) 12 normal prepubertal boys, 4) one prepubertal boy with the same form of TF. Each subject received i.m. a single dose of hCG 3500 IU/m2 b.s. and blood samples were collected basally and 2, 4, 24, 48, 72 and 96 hours after the hormonal stimulus. Serum levels of T, 17 alpha hydroxyprogesterone (17OHP) and 17 beta estradiol (E2) were measured at each collection time.
In normal men a significant increase in T (M +/- SE) was observed at 4 h (758.6 +/- 135 ng/dl, P less than 0.05) and a more significant increase at 48 h (1082 +/- 60.3 ng/dl, P less than 0.001). E2 and 17OHP peaked significantly at 24 h (81.5 +/- 9.6 pg/ml and 460.7 +/- 90.9 ng/dl respectively). This response pattern is characteristic of the testicular desensitization which occurs in normal man after a single hCG dose. The same response pattern has been observed in the two TF adult patients suggesting that human testicular desensitization in vivo does not depend on androgen receptors.(ABSTRACT TRUNCATED AT 250 WORDS)
PMID: 2793066 [PubMed - indexed for MEDLINE]