Hydrogen sulfide (H2S) is, like nitric oxide, an important gaseous mediator that has significant effects on the immunological, neurological, cardiovascular and pulmonary systems of mammals. Sodium hydrogen sulfide is an H2S donor commonly used in cellular and whole animal experimental systems. For example, it has...

Clobenpropit is a selective histamine H3 receptor antagonist (Ki = 0.17 nM in rat cortical membranes). Clobenpropit (0.3, 0.1, and 3 nM) reduces inhibition of electrically induced contractions in isolated guinea pig ileum longitudinal muscle by the H3 receptor agonist (R)-alpha-methylhistamine (Cay-25601). It does...

Thioperamide (maleate) is a selective histamine H3 receptor antagonist that crosses the blood-brain barrier. This compound binds to rat cerebral cortical cells in vitro with a pKi value of 8.4 and inhibits histamine binding in vivo with an ED50 value of 1 mg/kg. At a dose of 5 mg/kg thioperamide (maleate) inhibits...

Ribonucleotide reductase, the rate-limiting enzyme for de novo DNA synthesis, is a common target for chemotherapy. Its increased activity in cancer cells is associated with malignant transformation and proliferation. Trimidox is a specific ribonucleotide reductase inhibitor that reduces levels of dGTP and dCTP in...

Type 4 cyclic nucleotide phosphodiesterases (PDE4) isoforms selectively inactivate the second messenger cAMP by hydrolyzing the phosphodiester bond, producing AMP. (±)-Rolipram is a cell-permeable selective PDE4 inhibitor. Since PDE4 is abundant in leukocytes, (±)-rolipram inhibits inflammation by suppressing...