EFFECTS OF ACUTE ADMINISTRATION OF RECOMBINANT INTERFERON-ALPHA-2B ON PITUITARY-HORMONE SECRETION IN PATIENTS WITH CHRONIC ACTIVE HEPATITIS

The effect of a single intramuscular (IM) dose of 10 x 10(6) IU of recombinant interferon alpha-2b (alpha IFN) on adrenocorticotropin (ACTH), beta-endorphin (beta-EP), thyrotropin (TSH), growth hormone (GH), luteotropin (LH), and prolactin (PRL) was evaluated in seven patients suffering from chronic viral hepatitis (CVH). Alpha IFN increased ACTH (from 11.2 +/- 1.1 ng/L to 16.3 +/- 2.6 ng/L) and beta-EP (from 25.0 +/- 1.9 ng/L to 37.6 +/- 1.7 ng/L) plasma concentrations and lowered plasma TSH concentrations (from 2.4 +/- 0.4 mIU/L to 1.0 +/- 0.2 mIU/L). These effects were recorded between the fourth and the 12th hour after alpha IFN administration and occurred without significant variations in the remaining plasma hormonal levels. In seven additional patients who received a 3 x 10(6)-IU IM dose of the same IFN, no significant variations in ACTH, beta-EP, or TSH plasma levels were found. Data indicate that alpha IFN may influence the neural mechanisms controlling anterior pituitary secretion. However, high alpha IFN doses are required for this effect to occur.