Oscillating calcium signals in smooth muscle cells underlie the persistent basal tone of internal anal sphincter.

ABSTRACT: A persistent basal tone in the internal anal sphincter (IAS) is essential for keeping the anal canal closed and fecal continence; its inhibition via the rectoanal inhibitory reflex (RAIR) is required for successful defecation. However, cellular signals underlying the IAS basal tone remain enigmatic. Here we report the origin and molecular mechanisms of calcium signals that control the IAS basal tone, using a combination approach including a novel IAS slice preparation that retains cell arrangement and architecture as in vivo, 2-photon imaging, and cell-specific gene-modified mice. We found that IAS smooth muscle cells generate two forms of contractions (i.e., phasic and sustained contraction) and Ca²⁺ signals (i.e., synchronized Ca²⁺ oscillations [SCaOs] and asynchron

SUBMITTER: Lu P 

PROVIDER: S-EPMC8132622 | biostudies-literature | 2021 Aug

REPOSITORIES: biostudies-literature