The pulsatile secretion of gonadotropins and growth hormone, and the biological activity of luteinizing hormone in men acutely intoxicated with ethanol.
Level 3 - non-randomized controlled study
Non-randomized self-controlled crossover trial (fixed treatment order)
PubMed 2128439 · doi:10.1111/j.1530-0277.1990.tb01840.x
What was done
Eight healthy male volunteers aged 20 to 26 received 1.5 g/kg of oral ethanol over 3 hours (18:00 to 21:00). Blood was sampled every 20 minutes for 20 hours (until 14:00 the following day) to evaluate pulsatile secretion of immunoreactive LH, FSH, and growth hormone (GH), along with bioactive LH, testosterone, cortisol, and prolactin. Each participant repeated the identical protocol without ethanol at least 1 month later as a self-control.
What was found
Ethanol intake reduced serum testosterone by an average of 23% (p < 0.05) between 10 and 16 hours after drinking began. Mean levels, pulse frequency, and pulse amplitude of LH and FSH remained unchanged, and LH biological activity was unaffected. Alcohol reduced the nightly GH peak in all 8 subjects and shifted peak timing in most. Cortisol increased by an average of 36% (p < 0.05) between 11 and 14 hours, while prolactin exhibited only marginal changes.
Why it matters
These findings indicate that acute alcohol-induced testosterone decline is not driven by hypothalamic-pituitary gonadotropin failure or altered LH bioactivity, while confirming that acute intoxication profoundly blunts nocturnal growth hormone release.
Limits
The sample size was very small (n = 8) and restricted to young healthy men. The intervention was not randomized (ethanol was always administered before the control session), creating potential period or order effects. Exact numerical values and dispersion metrics for GH, LH, FSH, and prolactin were not reported in the abstract.
Cited by
- contradicts Acute alcohol consumption typically increases GnRH, LH, FSH, and estrogen/estradiol levels, while decreasing testosterone and progesterone levels.