Ethanol elimination by rats as a function of reproductive state, gender and nutritional status

Alcohol elimination was studied in rats of different ages, reproductive states and nutritional deprivation, with the following results: 1) blood levels of ethanol 180 min after a single dose of 1.5 g/kg, ip were significantly higher in adult male (74 days old, N=5) than in young male rats (34 days old, N = 5): 92.4 ñ 8.4 vs 6.8 + 3.4 mg/lOO ml, means ñ SD, respectively; 2) when male rats were given a low protein diet for 48 h, blood ethanol levels after a single dose were significantly increased in young males (38.6 ñ 14.6 mg/l00 ml) but no effect after a single dose was found in the same animals at an older age (93.2 ñ 5.0 mg/l00 ml); 3) blood levels in female rats were higher than in young males both in the virgin and pregnant states, but during lactation a significant drop in blood levels of ethanol was observed. Blood levels of ethanol (mg/l00 ml) 180 min after a single dose of 1.5 g/kg, ip, in females, were: virgin (N=6): 44.9 ñ 16. 1, pregnant (N = 5): 40.0 ñ 10.4, lactant (N = 5): 8.8 5.8. This difference between virgin and pregnant and lactant rats was not related to changes in ADH activity which did not differ between groups. The present study indicates that in male rats the effect of a short-term protein deprivation on ethanol elimination is dependent on the age of the animal. In females, reproductive state is an important factor in determining ethanol elimination.

Ethanol pharmacokinetics in lactating women

Experimental studies in rats have demonstrated that lactating females have blood ethanol levels five times lower than those observed in non-lactating rats. The purpose of the present study was to verify if this phenomenon also occurs in human beings. Five lactating (L) and five control (C) women received, after formal agreement to the experimental procedure, 0.4 g/kg of ethanol as vodka (Stolichnaya, USSR), between 9:00 and 10:15 a.m. Blood and milk samples were collected 10, 20, 40, 60, 90, 150 and 180 min after ethanol ingestion. Ethanol levels in blood and milk were measured by gas chromatography using the head space technique. Results indicated that: time to reach maximal blood levels was significantly longer in the L group (L: 48.0 +/- 10.9, C: 31.2 +/- 16.4 min, means +/- SD), area under the curve was smaller when group L was compared to group C (L: 3821.5 +/- 1240.5, C: 5154.8 +/- 1313.7 mg per cent x min, means +/- SD), ethanol blood levels (mg/dl) at 150 and 180 min were significantly lower in the L group (150: L, 10.5 +/- 5.6; C, 18.7 +/- 6.8; 180: L, 3.9 +/- 2.8; C, 13.2 +/- 6.4, means +/- SD). Concentration of ethanol in milk was similar to concentration in blood. These results indicate the importance of lactation for ethanol pharmacokinetics and raise questions about the pharmacokinetics of other drugs ingested by lactating women