EFFECT OF CHRONIC ETHANOL ADMINISTRATION AND ABSTINENCE ON SERUM THYROID-STIMULATING HORMONE, PROLACTIN AND GROWTH HORMONE CONCENTRATIONS IN RATS WITH HIGH AND LOW ETHANOL INTAKE

Serum anterior pituitary hormone levels of genetically selectedAA and ANA rats of Wistar origin as well as those of experimentallyselected heavy drinkers (HD) and light drinkers (LD) among normalWistar rats were studied. AA and HD rats consumed high doseswhile ANA and LD rats preferred low doses of ethanol. Serumthyroid-stimulating hormone (TSH), prolactin and growth hormone(GH) concentrations were measured by specific radio-immunoassaysbefore chronic ethanol administration, during physical dependenceand on subsequent withdrawal. Basal TSH levels and TSH responsesto cold were as a rule decreased in the course of ethanol intakeand abstinence, whereas the TRH-induced TSH elevation becamemore consistent than before ethanol. There was no differencein basal prolactin levels between ethanol preferring and non-preferringrats at abstinence, whereas 30 min cold-exposure seemed to decreasethem in HD and LD rats. The high prolactin levels before ethanoland during physical dependence appear to be caused by stressfactors involved in the blood collecting procedure. GH levelswere not significantly different in ANA, AA, LD and HD ratsand neither ethanol intake nor subsequent withdrawal consistentlymodified GH levels. It is concluded that the observed minoralterations in the levels of anterior pituitary hormones hardlyplay any significant role in the development of alcohol dependence.