Potent agonist for both PKR1/PROKR1 and PKR2/PROKR2 (PubMed:12054613). Potently contracts gastrointestinal (GI) smooth muscle (PubMed:10567694). Expressed by the venom gland. This toxin does not inhibit Kv1.1/KCNA1, Kv1.2/KCNA2, Kv1.3/KCNA3, Kv1.4/KCNA4, Kv1.5/KCNA5, Kv2.1/KCNB1, Kv3.4/KCNC4, Kv4.2/KCND2, K2P2.1/KCNK2, Kv11/KCNH, Kv7.1/KCNQ1, Kv7.2/KCNQ2, Kv7.3/KCNQ3, Kir1.1/KCNJ1, Kir2.1/KCNJ2, Kir2.2/KCNJ12, Kir3.1/KCNJ3-Kir3.2/KCNJ6 (GIRK1,2) and Kir3.1/KCNJ3-Kir3.4/KCNJ5 (GIRK1,4). Belongs to the AVIT (prokineticin) family.