Inhibition of the effects of alfathesin and other steroid anesthetics by catatoxic steroids in rats.

In rats, the sleeping time induced by overdosage with eight steroid anesthetics--alfathesin, 3-(3-oxo-17beta-hydroxy-19-nor-4-androsten-17alpha-yl)-propionic acid-lactone (SC-8109), 21-hydroxy=5alpha-pregnane-3,20-dione (P-234), 4-pregnene-3,11,20-trione (Bio.66), 17-hydroxy-3-oxo-4-androstene-17alpha-propionic acid-gamma-lactone(SC-5233),3alpha-hydroxy-5beta-pregnane-11,20-dione, 5beta-pregnane-3,11,20-trione (U-1373), and hydroxydione--was abolished or considerably reduced by a variety of catatoxic compounds, particularly 3beta-hydroxy-20-oxo-5-pregnene-16alpha-carbonitrile (PCN), 9alpha-fluoro-11beta,17-dihydroxy-3-oxo-4-androstene-17alpha-propionic acid potassium salt (CS-1), prednisolone, ethylestrenol and spironolactone. Phenobarbital and diphenylhydantoin, two non-steroidal stimulators of hepatic microsomal drug metabolism, were also highly effective. In contrast, triamcinolone, estradiol,progesterone, desoxycorticosterone and hydroxydione, which exert little or no catatoxic activity, failed to significantly diminish anesthesia or sedation.