β-cyano-L-Alanine (Synonyms: BCA)

Hydrogen sulfide (H2S) is a naturally-occurring gasotransmitter with vasodilator and inflammatory modulating activity. [1][2] H2S is synthesized naturally in a range of mammalian tissues principally by the activity of two enzymes, cystathionine γ lyase (CSE) and cystathionine β synthetase (CBS). β-cyano-L-Alanine (BCA) is a reversible inhibitor of the H2S-synthesizing enzyme CSE. [3]  BCA blocks H2S synthesis in rat liver preparations with an IC50 value of 6.5 µM and increases blood pressure in anaesthetized rats induced with hemorrhagic shock by inhibiting endogenous H2S synthesis. [4]  BCA at 50 mg/kg blocked both L-cysteine- and LPS-induced hyperalgesia in rats.[5]

Reference:
[1]. Li, L., and Moore, P.K. Putative biological roles of hydrogen sulfide in health and disease: A breath of not so fresh air? Trends in Pharamacological Sciences 29(2), 84-90 (2007).
[2]. Wang, R. Two’s company, three’s a crowd: Can H2S be the third endogenous gaseous transmitter? The FASEB Journal 16(13), 1792-1798 (2002).
[3]. Pfeffer, M., and Ressler, C. ß-cyanoalanine, an inhibitor of rat liver cystathionase. Biochemical Pharmacology 16, 2299-2308 (1967).
[4]. Mok, Y.Y.P., Atan, M.S.B.M., Ping, C.Y., et al. Role of hydrogen sulphide in haemorrhagic shock in the rat: Protective effect of inhibitors of hydrogen sulphide biosynthesis. British Journal of Pharmacology 143, 881-889 (2004).
[5]. Kawabata, A., Ishiki, T., Nagasawa, K., et al. Hydrogen sulfide as a novel nociceptive messenger. Pain 132, 74-81 (2008).