Calcium sulfide (CaS), a donor of hydrogen sulfide (H(2)S): a new antihypertensive drug?

Hypertension is the leading cause of cardiovascular diseases, and an estimated 972 million people in the world are suffering from this problem. Indubitably, hypertension is an important worldwide public-health challenge. In recent years many efforts have been made to devise novel therapies involving new targets implicated in cardiovascular diseases. Hydrogen sulfide (H(2)S) is a member of a growing family of "gasotransmitters". It is clear that H(2)S plays a pivotal role in the basal regulation of vessels tone. Also studies demonstrate that intravenous sodium hydrosulfide (NaHS), a donor of H(2)S, dose-dependently decreases systolic blood pressure. However, because of its active chemical property, NaHS can be easily oxidized, even spontaneously ignited in the open air. Moreover, its solution is not stable. So the pharmacal use of NaHS is limited by its properties. Calcium sulfide (CaS), one of the effective components in a traditional herb, is another donor of H(2)S. It has more stable chemical properties than NaHS. We hypotheses that CaS might be given by mouth as a new antihypertensive drug through certain dosage form designing. To test this hypothesis, we should establish animal models for studies including drug efficacy, drug safety, drug toxicology, drug metabolism and drug kinetics.