Telmisartan enhances voltage-gated Na+ currents and modulates action potential firing in excitable cells, according to integrated experimental and in silico models.
Telmisartan may directly enhance voltage-gated Na+ currents and modulate action potential firing in excitable cells, independent of its AT1 receptor antagonism.
Telmisartan (TEL) is a non-peptide, orally administered antihypertensive agent primarily known as angiotensin II type 1 (AT1) blocker. In this review, we provide a detailed overview of how TEL modulates voltage-gated Na+ current (INa) and affects action potential (AP) firing behavior. TEL exerts differential stimulatory effects on the peak and late components of INa when subjected to brief depolarizing pulses across a range of cell types, such as mHippoE-14 hippocampal neuron, cultured dorsal root ganglion neurons, and HL-1 atrial cardiomyocytes. TEL can augment the non-inactivating (persistent) INa elicited by ascending long ramp pulse in mHippoE-14 cells. By using a parvalbumin-expressing interneuron-based modeled cell combined with bifurcation analysis, it is possible to predict how applied current influences subthreshold oscillations and the generation of somatic spiking in the presence of TEL. According to the Hodgkin-Huxley model, mimicking the action of TEL—characterized by an increased peak amplitude of INa and a slowed inactivation time course—leads to the emergence of periodic oscillations in membrane potential. Using a Markovian process, a separate model can also be mathematically constructed, showing that changes in certain rate constants can simulate the effect of TEL on INa in cardiac cells. The molecular docking prediction between TEL and the NaV1.7 channel was made by expected formation of hydrophobic interactions as well as hydrogen bonding. In addition to its antagonistic action at the AT1 receptor and its agonistic activation of peroxisome proliferator-activator-γ, TEL may also directly enhance INa, thereby modulating AP firing in a variety of excitable cells. Current evidence supports TEL’s modulatory impact on NaV channel activity and cellular excitability, while also acknowledging that the mechanism—whether direct or indirect—remains under investigation.
Wu et al. (Sun,) reported a review. Telmisartan was evaluated. Telmisartan enhances voltage-gated Na+ currents and modulates action potential firing in excitable cells, according to integrated experimental and in silico models.