Effect of ethanol infusion on the pituitary-testicular responsiveness to gonadotropin releasing hormone and thyrotropin releasing hormone in normal males and in chronic alcoholics presenting with hypogonadism.
Level 2 - randomized trial
Small randomized crossover physiological challenge trial comparing two cohorts.
PubMed 6423720 · doi:10.1007/BF03348339
What was done
Nine chronic male alcoholics with hypogonadism (without overt liver failure) and 10 healthy male controls were evaluated under baseline conditions and during a 3-hour infusion of saline versus 0.4 g/kg ethanol. At 60 minutes into the infusion, subjects received intravenous gonadotropin-releasing hormone (GnRH, 100 µg) and thyrotropin-releasing hormone (TRH, 200 µg). A subgroup of six alcoholics and six controls also underwent a third test with 0.8 g/kg ethanol. Tests were administered in random order at intervals of at least three weeks following a 48-hour period of abstinence. Plasma levels of FSH, LH, prolactin, and testosterone were measured by radioimmunoassay.
What was found
Baseline 08:00 plasma samples over three consecutive days showed significantly higher FSH, LH, and prolactin, and significantly lower testosterone, in alcoholics versus controls (exact numerical values not reported in abstract). Infusion of 0.4 g/kg ethanol did not alter the GnRH and TRH response pattern in either group. Doubling the dose to 0.8 g/kg caused a significant reduction of LH response in normal subjects, but had no similar effect in alcoholics. The mean LH increment was significantly lower in alcoholics than in controls during saline and 0.4 g/kg ethanol infusions, but the difference was not statistically significant at the 0.8 g/kg dose.
Why it matters
This study demonstrates that acute high-dose alcohol directly blunts pituitary LH secretion in healthy males, whereas chronic alcoholics exhibit baseline pituitary-gonadal dysfunction that does not shift further with acute alcohol exposure.
Limits
The study is constrained by a very small sample size (n = 19 overall, n = 12 for the high-dose phase) and was restricted to males. The abstract provides no exact numerical values, effect estimates, or confidence intervals, and the text in the abstract was truncated.
Cited by
- contradicts Acute alcohol consumption typically increases GnRH, LH, FSH, and estrogen/estradiol levels, while decreasing testosterone and progesterone levels.