BK channel activation by L-type Ca²⁺ channels Ca_V1.2 and Ca_V1.3 during the subthreshold phase of an action potential.

ABSTRACT: Mammalian circadian (24 h) rhythms are timed by the pattern of spontaneous action potential firing in the suprachiasmatic nucleus (SCN). This oscillation in firing is produced through circadian regulation of several membrane currents, including large-conductance Ca²⁺- and voltage-activated K⁺ (BK) and L-type Ca²⁺ channel (LTCC) currents. During the day steady-state BK currents depend mostly on LTCCs for activation, whereas at night they depend predominantly on ryanodine receptors (RyRs). However, the contribution of these Ca²⁺ channels to BK channel activation during action potential firing has not been thoroughly investigated. In this study, we used a pharmacological approach to determine that both LTCCs and RyRs contribute to the baseline membr

SUBMITTER: Plante AE 

PROVIDER: S-EPMC8409951 | biostudies-literature | 2021 Aug

REPOSITORIES: biostudies-literature