Alcohol effects on LH and FSH in ovariectomized female monkeys

The acute effects of alcohol (2.5, 3.0, 3.5 g/kg) and sucrose control solution on basal levels of luteinizing hormone (LH) and follicle stimulating hormone (FSH) were compared in recently and chronically ovariectomized female rhesus monkeys. Integrated plasma samples were collected at 20 min intervals for 3 hr before and 6 hr after nasogastric intubation of alcohol or isocaloric sucrose control solution. Baseline levels of LH and FSH were significantly higher in recently than in chronically ovariectomized females (p less than 0.001). Baseline LH pulse frequency was also significantly higher (p less than 0.001) in the recently ovariectomized group than in the chronically ovariectomized group (0.704 +/- 0.03 vs. 0.379 +/- 0.10 pulses/hr). FSH pulse frequency was equivalent in both groups (0.444 +/- 0.06 to 0.360 +/- 0.06 pulses/hr). After 2.5 g/kg of alcohol, peak blood alcohol levels were 243 to 256 mg/dl and LH decreased significantly (p less than 0.01) in both groups. After 3.0 g/kg alcohol, peak blood alcohol levels were 237 to 289 mg/dl, and basal LH levels (p less than 0.05) and LH pulse frequency (p less than 0.05) decreased significantly only in the recently ovariectomized group. After 3.5 g/kg of alcohol, peak blood alcohol levels exceeded 320 mg/dl, and LH did not change significantly in either group. Administration of 3.5 g/kg alcohol was associated with increased LH pulse amplitude in some individuals. Since lower alcohol doses (2.5 and 3.0 g/kg) and sucrose control administration were followed by a significant decline in LH (p less than 0.05-0.01) and the highest alcohol dose (3.5 g/kg) was not, these data suggest the possible influence of nonspecific "stress" on modulation of LH secretory activity. FSH did not change after sucrose administration in recently ovariectomized monkeys, but was significantly suppressed after 2.5 and 3.5 g/kg alcohol (p less than 0.05). In the chronically ovariectomized monkeys, FSH decreased significantly after administration of sucrose and all alcohol doses. LH suppression was not consistently associated with changes in FSH in either group--a finding consonant with the hypothesis that LH and FSH may be controlled by different hypothalamic regulatory factors.