Moreover, a non-selective PDE inhibitor theophylline, when administered orally at a dose of 100 mg kg−1 to mice, increased plasma levels of cAMP up to 296.9 pmol mL−1 at 20 min post-dose (Cheng et al. 1997), whereas after i.p. dose of 50 mg kg−1 to rats with endotoxemia, it elevated concentrations of this nucleotide to 228.22 pmol mL−1 0.5 h after drug administration (our own unpublished data). The gene discussed is ALDH7A1; the disease is serum lipopolysaccharide activity.