EFFECTS OF A BACTERIAL POLYSACCHARIDE (PIROMEN®) ON THE PITUITARY-ADRENAL AXIS: CORTISONE BLOCKADE OF PIROMENINDUCED RELEASE OF ACTH

Abstract

The bacterial polysaccharide, Piromen, stimulates the pituitary to release ACTH. The intensity of the response varies with the dose of the drug employed. Certain aspects of the increased adrenal activity following Piromen are somewhat atypical, e.g., failure of the thymus to involute in animals, and positive nitrogen balance in humans. An attempt was made to determine whether the ACTH-releasing effects of this drug could be blocked by pre-existing levels of steroid. Male, 100 gm rats were pre-treated with cortisone, desoxycorticosterone, followed by a triggering dose of Piromen known to cause ACTH release. When adequate time was given to effect complete absorption of cortisone (pre-injection) the response to Piromen was completely blocked. Desoxycorticosterone had no effect. It is concluded that the pituitary-stimulating effects of Piromen are largely governed by pre-existing levels of circulating steroids especially of the glucocorticoid variety.