Effects of Alcohol on Plasma Testosterone and Luteinizing Hormone Levels Jack H. Mendelson, M.D.. James Ellingboe, Ph.D., Nancy K. Mello, Ph.D., and J o h n Kuehnle The findings obtained in this study indicate that the major effect of ethanol on plasma testosterone levels is occurring at a peripheral (testicular) rather than central (hypothalamicpituitary) site.
I
N 1926, Silvestrini’ reported the presence of testicular atrophy and gynecomastia in male alcoholics who also had alcohol-induced liver disease. The mechanisms underlying testicular atrophy and gynecomastia have been a matter of concern for physicians who treat patients with alcohol-related problems. Galvao-Teles and his associates2 concluded that a derangement in androgen metabolism was the primary factor associated with gynecomastia and testicular atrophy in alcoholic patients. Van Thiel and his associates3 concluded that a dual effect. alcohol-induced gonadal failure and hypothalamic-pituitary suppression, was present in males who had alcohol-related liver disease. Van Thiel et al.‘ were also able to produce hypogonadism in rats that were administered large doses of alcohol. Findings in experimental animals obtained by Van Thiel et al. were in agreement with those previously reported by Badr and Bartke,5 who found that alcohol produced dose-related decrements in testosterone levels in mice. In addition to direct effects of alcohol on gonadal function, there are data that indicate that alcohol-induced changes in hepatic function may affect gonadal steroid levels. Rubin et aL6 reported that chronic ethanol intake may increase hepatic testosterone A-ring reductase activity with concomitant acceleration of the rate of testosterone biotransformation. Gordon and his colleagues’ have observed the effects of chronic ethanol administration for periods up to 4 wk on plasma testosterone and gonadotropin levels in normal males. They reported, a “dampening of the episodic bursts of testosterone secretion followed by a fall in the plasma level of the steroid” during the first 5 days of alcohol administration. An additional fall in plasma testosterone levels occurred when alcohol was administered chronically for 12- 14 days. Gordon et a].’ found that chronic alcohol
intake reduced the production rate of testosterone but increased the metabolic clearance rate. Data obtained with respect to plasma luteinizing hormone levels suggested that ethanol was acting in an inhibitory manner at two sites: hypothalamic-pituitary and gonadal levels. In 1974, we conducted a series of studies to determine the effects of chronic ethanol intake on plasma testosterone levels in male alcohol addicts.* We found that chronic ethanol intake produced a significant suppression in plasma testosterone levels and that the degree of suppression correlated with blood ethanol values. In these studies, daily morning plasma testosterone levels prior to, during, and following chronic ethanol intake were obtained over periods of 26-28 consecutive days. However, it is now known that there may be very wide variations in plasma testosterone levels in normal healthy males.9 Thus, assessment of any potential drug or alcohol effects on testosterone and gonadotropin levels must take into account not only circadian differences but ultradian variation as well. Therefore, our most recent studies have been designed to measure plasma levels of testosterone and luteinizing hormone at frequent‘intervals and to correlate changes in these hormone levels with specific values on the blood alcohol curve. MATERIALS AND METHODS Adult male volunteers provided informed consent to participate in these studies. All of the male subjects (mean age, 23 yr) had no past or current history of alcohol or drug abuse or mental or physical illness. Physical and laboratory examinations for all subjects were within normal limits. Plasma samples were collected from a chronic indwelling intravenous catheter prior to and following alcohol adminisFrom the Alcohol and Drug Abuse Research Center. Harvard Medical School-McLean Hospital, Belmont. MllSS.
Supported in part by Grant DA 01676-01 from the National Institute on Drug Abuse. Reprint requests should be addressed to Jack H. Mendelson. M . D . . Alcohol and Drug Abuse Research Cenier. McLean Hospital, I15 Mill Street, Belmoni, Mass. 02178. @ 1978 by Grune & Straiton. Inc. 01454008/78/0203-0032~01 .oo/o
Alcoholism: Clinicaland Experimental Research, Vol. 2 . No. 3 (July). 1978
255
MENDELSON ET AL
256
tration. Plasma samples were collected every 20 min for a period beginning I hr prior to alcohol administration and continuing through 5 hr following alcohol intake. Plasma testosterone concentrations were determined using a highly specific double-antibody radioimmunoassay procedure previously described in detail.'O Plasma testosterone inter- and intra-assay coefficients of variation were 13%, 13%. and 60% as determined by analysis of controls having mean concentrations of 1200, 631, and 160 ng/100 ml, respectively. The error inherent in the assay method was similar between and within assays. As used for this study, the method had a practical lower limit of sensitivity of about 250 ng/ 100 ml. Plasma luteinizing hormone concentrations were measured using a double-antibody method similar to that described by Midgley.ll Results are expressed as nanograms of LER-907 per milliliter of plasma based on a secondary standard purchased from Serono Laboratories, Boston, Mass. Plasma luteinizing hormone intra- and interassay precisions were 4% and 175%.respectively, for a control with a mean luteinizing hormone concentration of96 ng/ml. To minimize differences due to larger interassay variance, all samples from a single subject were assayed in the same assay batch. As used in these studies, the luteinizing hormone assay had a lower limit of sensitivity of about 5 ng/ml. BLOOO ALCOHOL CWM
.
ASCENMNG
PEAK
To determine if the presence of ethanol in the plasma samples would interfere with the luteinizing hormone (LH) radioimmunoassay, 6 replicates of each of the 2 control plasma samples (mean LH 93 and 145 mg/ml) were analyzed with and without 100 mg/100 ml of ethanol. The same concentration of ethanol was also added to a serially diluted luteinizing hormone standard, analyzed in triplicate, which constituted the standard curve. No differences were found when comparing control plasma samples or standards assayed in the presence or absence of ethanol. RESULTS
Figure 1 presents plasma testosterone and luteinizing hormone levels during the ascending, peak, and descending phases of the blood alcohol curve for 16 normal adult males. Computation of plasma testosterone and luteinizing hormone levels was carried out by obtaining the mean level for all values determined on the ascending, peak, and descending phases of the blood alcohol curve. Plasma testosterone levels and plasma luteinizing hormone levels were within the normal
DESCEWlNQ
1
950
850
750
650
550
70
1
1
T 60
50 40
30
R
-B
636
+a4
+2m
0
3.3
4.4
2.4
R
0
BI
104
59
SE
0
72
46
23
Fig. 1. Plasma testosterone and luteinizing hormono levels during the ascending, peak, and descending phases of the blood alcohol curve for 16 normal adult males. Computation of plasma testosterone and luteinizing hormone levels was carried out by obtaining the mean level for all values determined on the ascending, peak, and descending phases of the blood alcohol curve. (Reproduced by permission.Is)
PLASMA TESTOSTERONE AND LH LEVELS
adult male range for all subjects prior to alcohol administration. After alcohol intake and during the ascending limb of the blood alcohol curve, there was a significant fall ( p < 0.05) in plasma testosterone levels. A further decrement in plasma testosterone levels was observed when peak blood alcohol levels occurred ( p < 0.01). During the ascending phase of the blood alcohol curve, there was no significant increase in plasma luteinizing hormone levels. However, plasma luteinizing hormone levels were significantly elevated when blood alcohol levels were at peak values ( p < 0.01). During the descending phase of the blood alcohol curve, plasma testosterone levels were significantly lower than pre-alcohol values ( p < 0.01). DISCUSSION
The findings obtained in this study indicate that the major effect of ethanol on plasma testosterone levels is occurring at a peripheral (testicular) rather than central (hypothalamic-pituitary) site. I f alcohol suppressed testosterone production via an initial suppression of hypothalamic-pituitary function, a decrease in plasma luteinizing hormone levels should have been observed antecedent to changes in plasma testosterone levels. We have observed that opiates depress plasma testosterone levels via initial suppression of luteinizing hormone secretion from the pituitary.” In contrast to opiates, alcohol produces a significant increase in plasma luteinizing hormone levels when blood alcohol levels are highest and plasma testosterone levels are lowest. The most parsimonious explanation for this phenomenon is that alcohol-induced decrements in plasma testosterone levels result in “long loop” feedback effects on hypothalamic-pituitary mechanisms that produce a surge in luteinizing hormone secretion. This mechanism would be expected to operate in any situation where plasma testosterone levels were lowered. In studies with rats, Cicero and his colleague^'^ found that alcohol does act at hypothalamic-pituitary sites, and they have postulated that alcohol decreases secretion of L H R H from t h e hypothalamus. The discrepancy between these findings and those obtained in our study may be based on species differences. On the other hand, differences may also be related to dosage factors and route of administration.
2 57
The effects of alcohol on steroidogenesis in the testes have not been studied in detail. Pilot studies carried out in our laboratory“ with decapsulated testes preparations indicate that alcohol produces a direct suppression of the biosynthesis of testosterone in a dose-related manner. Current studies are in progress to determine the basic mechanisms involved in this suppressive effect. For example, it would be important to determine if alcohol was acting to interfere with membrane permeability, second messenger systems, or depletion of cofactors (as a consequence of ethanol catabolism) required for steroidogenesis in the testes. There are a number of important questions concerning the behavioral significance of alcohol-induced changes in gonadal steroids and pituitary peptides, such as luteinizing hormone. For example, is it possible that increments in plasma luteinizing hormone, associated with initial decrements in plasma testosterone levels, may produce some alterations in sexual and aggressive behavior? Although sexual arousal in males may increase during alcohol intoxication, sexual performance is frequently compromised. These behavioral phenomena would be consistent with observed increments in plasma luteinizing hormone levels, but with decrements in plasma testosterone levels. Moreover, these behavioral-neuroendocrine relationships following acute alcohol intake are in marked contrast to those that occur following opiate administration. As noted previously, opiates produce a suppression i n luteinizing hormone levels followed by a decrement in plasma testosterone levels. I Z Behaviorally, opiates tend to decrease both aggressive and sexual behavior; opiate addicts often report both loss of libido and impairment in sexual performance. We postulate that increased libidinal drive and aggressive behavior following acute alcohol intake by males are associated with neural mechanisms that also regulate the secretory activity of gonadotropic hormones. REFERENCES 1. Silvestrini R: Gynecomastia. Reforma Med 142:701, 1926 2. Galvao-Teles A, Anderson DC, Burke GW, et a]: Biologically active androgen and estradiol in men with chronic liver disease. Lancet 1:173-177, 1973 3. Van Thiel DH, Lester R, Sherins RJ: Hypogonadism in alcoholic liver disease: Evidence for a double defect. Gastroenterology 67:1188-1199,1974
2 58
4. Van Thiel DH, Gavaler J. Lester R, et al: Alcohol-induced testicular atrophy. Gastroenterology 69:326-332, I975 5. Badr F, Bartke A: Effect of ethyl alcohol on plasma testosterone level in mice. Steroids 23:921-928. 1974 6. Rubin E. Lieber CS, Altman K, et al: Testosterone metabolism in the liver. Science 191563-564, 1976 7. Gordon GG,Altman K, Southren AL, et al: Effect of alcohol (ethanol) administration on sex-hormone metabolism in normal men. N Engl J Med 295:793-797, 1976 8. Mendelson JH, Mello NK: Alcohol, aggression and androgens. Res Pub1 Assoc Res Nerv Ment Dis 52:225-247, 1974 9. Alford PP, Baker HWG, Patel YC, et al: Temporal patterns of circulating hormones as assessed by continuous blood sampling. J Clin Endocrinol Metab 36:108-116, 1973 10. Mendelson JH, Kuehnle JC, Ellingboe J, et al: Plasma testosterone levels before, during and after chronic marihuanasmoking. N Engl J Med 291:1051-1055, 1974
MENDELSON ET AL.
I I . Midgley AR: Radioimmunoassay: A method for human chronic gonadotropin and human luteinizing hormone. Endocrinology 79:lO- 18, 1966 12. Mirin SM, Mendelson JH, Ellingboe J, et al: Acute effects of heroin and naltrexone on testosterone and gonadotropin secretion: A pilot study. Psychoneuroendocrinology 1:359-369, 1976
13. Cicero TJ, Bernstein D. Badger TM: Effects of acute alcohol administration on reproductive endocrinology in the male rat. Alcohol Clin Exp Res 2:249-254, 1978 14. Ellingboe J, Varanelli C: Effects of ethanol on testosterone production in isolated rat Leydig cell preparations. (in preparation) 15. Mendelson JH, Mello NK, Ellingboe J, et al: Effects of acute alcohol intake on pituitary-gonadal hormones in
normal human males. J Pharmacol Exp Ther 202:676-682, 1977
I
N 1926, Silvestrini’ reported the presence of testicular atrophy and gynecomastia in male alcoholics who also had alcohol-induced liver disease. The mechanisms underlying testicular atrophy and gynecomastia have been a matter of concern for physicians who treat patients with alcohol-related problems. Galvao-Teles and his associates2 concluded that a derangement in androgen metabolism was the primary factor associated with gynecomastia and testicular atrophy in alcoholic patients. Van Thiel and his associates3 concluded that a dual effect. alcohol-induced gonadal failure and hypothalamic-pituitary suppression, was present in males who had alcohol-related liver disease. Van Thiel et al.‘ were also able to produce hypogonadism in rats that were administered large doses of alcohol. Findings in experimental animals obtained by Van Thiel et al. were in agreement with those previously reported by Badr and Bartke,5 who found that alcohol produced dose-related decrements in testosterone levels in mice. In addition to direct effects of alcohol on gonadal function, there are data that indicate that alcohol-induced changes in hepatic function may affect gonadal steroid levels. Rubin et aL6 reported that chronic ethanol intake may increase hepatic testosterone A-ring reductase activity with concomitant acceleration of the rate of testosterone biotransformation. Gordon and his colleagues’ have observed the effects of chronic ethanol administration for periods up to 4 wk on plasma testosterone and gonadotropin levels in normal males. They reported, a “dampening of the episodic bursts of testosterone secretion followed by a fall in the plasma level of the steroid” during the first 5 days of alcohol administration. An additional fall in plasma testosterone levels occurred when alcohol was administered chronically for 12- 14 days. Gordon et a].’ found that chronic alcohol
intake reduced the production rate of testosterone but increased the metabolic clearance rate. Data obtained with respect to plasma luteinizing hormone levels suggested that ethanol was acting in an inhibitory manner at two sites: hypothalamic-pituitary and gonadal levels. In 1974, we conducted a series of studies to determine the effects of chronic ethanol intake on plasma testosterone levels in male alcohol addicts.* We found that chronic ethanol intake produced a significant suppression in plasma testosterone levels and that the degree of suppression correlated with blood ethanol values. In these studies, daily morning plasma testosterone levels prior to, during, and following chronic ethanol intake were obtained over periods of 26-28 consecutive days. However, it is now known that there may be very wide variations in plasma testosterone levels in normal healthy males.9 Thus, assessment of any potential drug or alcohol effects on testosterone and gonadotropin levels must take into account not only circadian differences but ultradian variation as well. Therefore, our most recent studies have been designed to measure plasma levels of testosterone and luteinizing hormone at frequent‘intervals and to correlate changes in these hormone levels with specific values on the blood alcohol curve. MATERIALS AND METHODS Adult male volunteers provided informed consent to participate in these studies. All of the male subjects (mean age, 23 yr) had no past or current history of alcohol or drug abuse or mental or physical illness. Physical and laboratory examinations for all subjects were within normal limits. Plasma samples were collected from a chronic indwelling intravenous catheter prior to and following alcohol adminisFrom the Alcohol and Drug Abuse Research Center. Harvard Medical School-McLean Hospital, Belmont. MllSS.
Supported in part by Grant DA 01676-01 from the National Institute on Drug Abuse. Reprint requests should be addressed to Jack H. Mendelson. M . D . . Alcohol and Drug Abuse Research Cenier. McLean Hospital, I15 Mill Street, Belmoni, Mass. 02178. @ 1978 by Grune & Straiton. Inc. 01454008/78/0203-0032~01 .oo/o
Alcoholism: Clinicaland Experimental Research, Vol. 2 . No. 3 (July). 1978
255
MENDELSON ET AL
256
tration. Plasma samples were collected every 20 min for a period beginning I hr prior to alcohol administration and continuing through 5 hr following alcohol intake. Plasma testosterone concentrations were determined using a highly specific double-antibody radioimmunoassay procedure previously described in detail.'O Plasma testosterone inter- and intra-assay coefficients of variation were 13%, 13%. and 60% as determined by analysis of controls having mean concentrations of 1200, 631, and 160 ng/100 ml, respectively. The error inherent in the assay method was similar between and within assays. As used for this study, the method had a practical lower limit of sensitivity of about 250 ng/ 100 ml. Plasma luteinizing hormone concentrations were measured using a double-antibody method similar to that described by Midgley.ll Results are expressed as nanograms of LER-907 per milliliter of plasma based on a secondary standard purchased from Serono Laboratories, Boston, Mass. Plasma luteinizing hormone intra- and interassay precisions were 4% and 175%.respectively, for a control with a mean luteinizing hormone concentration of96 ng/ml. To minimize differences due to larger interassay variance, all samples from a single subject were assayed in the same assay batch. As used in these studies, the luteinizing hormone assay had a lower limit of sensitivity of about 5 ng/ml. BLOOO ALCOHOL CWM
.
ASCENMNG
PEAK
To determine if the presence of ethanol in the plasma samples would interfere with the luteinizing hormone (LH) radioimmunoassay, 6 replicates of each of the 2 control plasma samples (mean LH 93 and 145 mg/ml) were analyzed with and without 100 mg/100 ml of ethanol. The same concentration of ethanol was also added to a serially diluted luteinizing hormone standard, analyzed in triplicate, which constituted the standard curve. No differences were found when comparing control plasma samples or standards assayed in the presence or absence of ethanol. RESULTS
Figure 1 presents plasma testosterone and luteinizing hormone levels during the ascending, peak, and descending phases of the blood alcohol curve for 16 normal adult males. Computation of plasma testosterone and luteinizing hormone levels was carried out by obtaining the mean level for all values determined on the ascending, peak, and descending phases of the blood alcohol curve. Plasma testosterone levels and plasma luteinizing hormone levels were within the normal
DESCEWlNQ
1
950
850
750
650
550
70
1
1
T 60
50 40
30
R
-B
636
+a4
+2m
0
3.3
4.4
2.4
R
0
BI
104
59
SE
0
72
46
23
Fig. 1. Plasma testosterone and luteinizing hormono levels during the ascending, peak, and descending phases of the blood alcohol curve for 16 normal adult males. Computation of plasma testosterone and luteinizing hormone levels was carried out by obtaining the mean level for all values determined on the ascending, peak, and descending phases of the blood alcohol curve. (Reproduced by permission.Is)
PLASMA TESTOSTERONE AND LH LEVELS
adult male range for all subjects prior to alcohol administration. After alcohol intake and during the ascending limb of the blood alcohol curve, there was a significant fall ( p < 0.05) in plasma testosterone levels. A further decrement in plasma testosterone levels was observed when peak blood alcohol levels occurred ( p < 0.01). During the ascending phase of the blood alcohol curve, there was no significant increase in plasma luteinizing hormone levels. However, plasma luteinizing hormone levels were significantly elevated when blood alcohol levels were at peak values ( p < 0.01). During the descending phase of the blood alcohol curve, plasma testosterone levels were significantly lower than pre-alcohol values ( p < 0.01). DISCUSSION
The findings obtained in this study indicate that the major effect of ethanol on plasma testosterone levels is occurring at a peripheral (testicular) rather than central (hypothalamic-pituitary) site. I f alcohol suppressed testosterone production via an initial suppression of hypothalamic-pituitary function, a decrease in plasma luteinizing hormone levels should have been observed antecedent to changes in plasma testosterone levels. We have observed that opiates depress plasma testosterone levels via initial suppression of luteinizing hormone secretion from the pituitary.” In contrast to opiates, alcohol produces a significant increase in plasma luteinizing hormone levels when blood alcohol levels are highest and plasma testosterone levels are lowest. The most parsimonious explanation for this phenomenon is that alcohol-induced decrements in plasma testosterone levels result in “long loop” feedback effects on hypothalamic-pituitary mechanisms that produce a surge in luteinizing hormone secretion. This mechanism would be expected to operate in any situation where plasma testosterone levels were lowered. In studies with rats, Cicero and his colleague^'^ found that alcohol does act at hypothalamic-pituitary sites, and they have postulated that alcohol decreases secretion of L H R H from t h e hypothalamus. The discrepancy between these findings and those obtained in our study may be based on species differences. On the other hand, differences may also be related to dosage factors and route of administration.
2 57
The effects of alcohol on steroidogenesis in the testes have not been studied in detail. Pilot studies carried out in our laboratory“ with decapsulated testes preparations indicate that alcohol produces a direct suppression of the biosynthesis of testosterone in a dose-related manner. Current studies are in progress to determine the basic mechanisms involved in this suppressive effect. For example, it would be important to determine if alcohol was acting to interfere with membrane permeability, second messenger systems, or depletion of cofactors (as a consequence of ethanol catabolism) required for steroidogenesis in the testes. There are a number of important questions concerning the behavioral significance of alcohol-induced changes in gonadal steroids and pituitary peptides, such as luteinizing hormone. For example, is it possible that increments in plasma luteinizing hormone, associated with initial decrements in plasma testosterone levels, may produce some alterations in sexual and aggressive behavior? Although sexual arousal in males may increase during alcohol intoxication, sexual performance is frequently compromised. These behavioral phenomena would be consistent with observed increments in plasma luteinizing hormone levels, but with decrements in plasma testosterone levels. Moreover, these behavioral-neuroendocrine relationships following acute alcohol intake are in marked contrast to those that occur following opiate administration. As noted previously, opiates produce a suppression i n luteinizing hormone levels followed by a decrement in plasma testosterone levels. I Z Behaviorally, opiates tend to decrease both aggressive and sexual behavior; opiate addicts often report both loss of libido and impairment in sexual performance. We postulate that increased libidinal drive and aggressive behavior following acute alcohol intake by males are associated with neural mechanisms that also regulate the secretory activity of gonadotropic hormones. REFERENCES 1. Silvestrini R: Gynecomastia. Reforma Med 142:701, 1926 2. Galvao-Teles A, Anderson DC, Burke GW, et a]: Biologically active androgen and estradiol in men with chronic liver disease. Lancet 1:173-177, 1973 3. Van Thiel DH, Lester R, Sherins RJ: Hypogonadism in alcoholic liver disease: Evidence for a double defect. Gastroenterology 67:1188-1199,1974
2 58
4. Van Thiel DH, Gavaler J. Lester R, et al: Alcohol-induced testicular atrophy. Gastroenterology 69:326-332, I975 5. Badr F, Bartke A: Effect of ethyl alcohol on plasma testosterone level in mice. Steroids 23:921-928. 1974 6. Rubin E. Lieber CS, Altman K, et al: Testosterone metabolism in the liver. Science 191563-564, 1976 7. Gordon GG,Altman K, Southren AL, et al: Effect of alcohol (ethanol) administration on sex-hormone metabolism in normal men. N Engl J Med 295:793-797, 1976 8. Mendelson JH, Mello NK: Alcohol, aggression and androgens. Res Pub1 Assoc Res Nerv Ment Dis 52:225-247, 1974 9. Alford PP, Baker HWG, Patel YC, et al: Temporal patterns of circulating hormones as assessed by continuous blood sampling. J Clin Endocrinol Metab 36:108-116, 1973 10. Mendelson JH, Kuehnle JC, Ellingboe J, et al: Plasma testosterone levels before, during and after chronic marihuanasmoking. N Engl J Med 291:1051-1055, 1974
MENDELSON ET AL.
I I . Midgley AR: Radioimmunoassay: A method for human chronic gonadotropin and human luteinizing hormone. Endocrinology 79:lO- 18, 1966 12. Mirin SM, Mendelson JH, Ellingboe J, et al: Acute effects of heroin and naltrexone on testosterone and gonadotropin secretion: A pilot study. Psychoneuroendocrinology 1:359-369, 1976
13. Cicero TJ, Bernstein D. Badger TM: Effects of acute alcohol administration on reproductive endocrinology in the male rat. Alcohol Clin Exp Res 2:249-254, 1978 14. Ellingboe J, Varanelli C: Effects of ethanol on testosterone production in isolated rat Leydig cell preparations. (in preparation) 15. Mendelson JH, Mello NK, Ellingboe J, et al: Effects of acute alcohol intake on pituitary-gonadal hormones in
normal human males. J Pharmacol Exp Ther 202:676-682, 1977
