Toxin
Imperatoxin I (IpTx) is a peptide toxin derived from the venom of the African scorpion Pandinus imperator.
There are two subtypes of this toxin:
- Imperatoxin A (activator): a peptide toxin which enhances the influx of Ca2+ from the sarcoplasmatic reticulum into the cell.
- Imperatoxin I (inhibitor): a peptide toxin which decreases the influx of Ca2+ from the sarcoplasmatic reticulum into the cell.