L-type Ca²⁺ Channels at Low External Calcium Differentially Regulate Neurotransmitter Release in Proximal-Distal Compartments of the Frog Neuromuscular Junction.

ABSTRACT: L-type Ca²⁺ channels (LTCCs) are key elements in electromechanical coupling in striated muscles and formation of neuromuscular junctions (NMJs). However, the significance of LTCCs in regulation of neurotransmitter release is still far from understanding. Here, we found that LTCCs can increase evoked neurotransmitter release (especially asynchronous component) and spontaneous exocytosis in two functionally different compartment of the frog NMJ, namely distal and proximal parts. The effects of LTCC blockage on evoked and spontaneous release as well as timing of exocytotic events were prevented by inhibition of either protein kinase C (PKC) or P2Y receptors (P2Y-Rs). Hence, endogenous signaling via P2Y-R/PKC axis can sustain LTCC activity. Application of ATP, a co-neurotransmitter

SUBMITTER: Tsentsevitsky AN 

PROVIDER: S-EPMC11421649 | biostudies-literature | 2022 Nov

REPOSITORIES: biostudies-literature