OD1 is a scorpion peptide that has been isolated initially from the venom of the scorpion Odonthobuthus doriae. OD1 potently inhibits fast inactivation of mammalian channels Na_v1.7 (EC50 4.5 nM), Na_v1.4 (EC₅₀ 10 ± 2 nM) and Na_v1.6 (EC₅₀ 47 ± 10 nM). OD1 also blocks fast inactivation of the para/tipE insect channel (EC₅₀ 80 nM). OD1 weakly affects mammalian Na_v1.3 and Na_v1.5 (EC₅₀ > 1 μM) and does not affect Na_v1.2 and Na_v1.8. OD1 induces spontaneous pain when injected in animal in association with our without Veratridine and can be used to test the analgesic effects of Na_v1.7 blockers in-vivo.

A, C, Time course of the modulating effect of OD1 #ODX001 (50 nM) on hNav1.7 current.  The current was elicited by a 50 ms-depolarizing pulse to -25 mV (estimated V_1/2) or to -10 mV from a holding potential of -90 mV. Inter-sweep period was 10 s. Current amplitudes were plotted against time. Black bar indicates toxin application. B, D, Representative recording traces of Nav1.7 current in control condition (black) and after the effect of OD1 #ODX001 had stabilized (red). The inactivation kinetics of current was fitted with the standard mono-exponential function. E, Families of hNav1.7 current traces in control and in the presence of 50 nM OD1 #ODX001. Currents were evoked by depolarizing pulses from -60 mV to 40 mV, while the cell was hold at -90 mV. F, Amplitude-voltage relationships obtained from E.

AA sequence:   GVRDAYIADDKNCVYTCASNGYCNTECTKNGAESGYCQWIGRYGNACWCIKLPDEVPIRIPGKCR-NH₂
Disulfide bonds:   C13-C64 ; C17-C37 ; C23-C47 ; C27-C49
Length (aa): 65
Formula:  C₃₀₈H₄₆₆N₉₀O₉₅S₈
Appearance: White lyophilized solid
CAS number: Not available
Molecular Weight: 7206.20 Da
Source: Synthetic
Counterion: TFA salts
Solubility: Water or saline buffer, 5 mg/mL maximum (recommendation)
Purity: >95%