CA2-OXIDE CGMP SIGNALING IN RABBIT PAROTID ACINAR-CELLS( NITRIC)

Guanosine 3',5'-cyclic monophosphate (cGMP) is a second messenger gene rated in response to hormones or neurotransmitters in various tissues and cells. In parotid acinar cells, the activation of muscarinic choli nergic and beta-adrenergic receptors induces an increase in intracellu lar cGMP. However, the mechanism of cGMP production in parotid acinar cells has not been well elucidated, cGMP production is induced by the activation of guanylyl cyclases, which are directly activated by nitri c oxide (NO). NO plays an important role as an inter- and intracellula r signal molecule in various organs and cells. Biosynthesis of NO is c atalyzed by KO synthase (NOS), and NO generation is controlled by the regulation of NOS activity, for example by Ca2+. We have studied the r egulation of NOS activity, NO generation and cGMP production in rabbit parotid acinar cells, and have demonstrated a functional Ca2+-NO-cGMP signaling pathway.