Different mechanisms underlying the stimulation of K(Ca) channels by nitric oxide and carbon monoxide.

ABSTRACT: The molecular mechanisms underlying the effects of nitric oxide (NO) and carbon monoxide (CO), individually and collectively, on large-conductance calcium-activated K(+) (K(Ca)) channels were investigated in rat vascular smooth muscle cells (SMCs). Both NO and CO increased the activity of native K(Ca) channels. Dehydrosoyasaponin-I, a specific agonist for beta subunit of K(Ca) channels, increased the open probability of native K(Ca) channels only when it was delivered to the cytoplasmic surface of membrane. CO, but not NO, further increased the activity of native K(Ca) channels that had been maximally stimulated by dehydrosoyasaponin-I. After treatment of SMCs with anti-K(Ca),beta subunit antisense oligodeoxynucleotides, the stimulatory effect of NO, but not of CO, on K(Ca) channels was nu

SUBMITTER: Wu L 

PROVIDER: S-EPMC151105 | biostudies-literature | 2002 Sep

REPOSITORIES: biostudies-literature