From the Research
Baclofen and Calcium Interaction
- Baclofen has been shown to interact with calcium channels in various studies 1, 2, 3, 4, 5
- The interaction between baclofen and calcium channels can lead to a reduction in presynaptic calcium influx, which in turn can reduce excitatory transmitter release 2, 3, 5
- Baclofen has been found to inhibit L-type-like voltage-dependent calcium channels in cerebellar granule cell cultures with a half maximal effective concentration of 4 nM 2
- The inhibition of calcium channels by baclofen can be modulated by guanine nucleotides, with GTP-gamma-S increasing the ability of baclofen to inhibit calcium-channel currents 4
- Baclofen has also been shown to reduce the duration of orthodromic action potentials in muscle group Ia afferent terminations, which is consistent with a reduction in presynaptic calcium influx 5
Mechanism of Action
- The mechanism of action of baclofen involves the activation of GABAB receptors, which can lead to a reduction in presynaptic calcium influx 1, 3, 5
- The reduction in presynaptic calcium influx can lead to a decrease in excitatory transmitter release, which can contribute to the therapeutic effects of baclofen in the treatment of spasticity 1, 3, 5
- Baclofen may also interact with other ion channels, such as potassium channels, but the evidence suggests that the primary mechanism of action involves the inhibition of calcium channels 2, 4, 5
Concentration-Dependent Effects
- The effects of baclofen on calcium channels are concentration-dependent, with nanomolar concentrations being effective in inhibiting calcium-channel currents 2, 4
- The half maximal effective concentration of baclofen for inhibiting calcium-channel currents can vary depending on the specific conditions and cell type, but is generally in the range of 1-10 nM 2, 4