Potentiates ASIC3 currents (homotrimer and ASIC1a-ASIC3, ASIC1b-ASIC3, ASIC2a-ASIC3 and ASIC2b-ASIC3 heterotrimers) (PubMed:28396446). It increases the peak current amplitude of ASIC3 homotrimer by 1.48-fold (PubMed:28396446). In addition, it slows the desensitization kinetics of ASIC3 (homotrimer and heterotrimer-containing ASIC3) (PubMed:28396446). The current amplitude at the end of a 10-second proton pulse of ASIC3 homotrimer is 26% instead of 1% without the peptide (PubMed:28396446). It strongly acts by binding to the channel in the closed state (PubMed:28396446). It shows a higher affinity for ASIC3 homotrimers than does CNF-Tx1.2 (PubMed:28396446). It changes the apparent proton affinity of ASIC3 (to higher pH for potentiation and to lower pH for desensitization) (PubMed:28396446). It competes with FMRFamide (AC P69145) for a common binding site (PubMed:28396446). In vivo, intramuscular injection into mice enhances acid-induced muscle pain (PubMed:28396446). Potentiates ASIC3 (homotrimer) currents (PubMed:28396446) and heterotrimer-containing ASIC3 (Probable). It increases the peak current amplitude of ASIC3 homotrimer by 1.2-fold (PubMed:28396446). In addition, it slows the desensitization kinetics of ASIC3 (the current amplitude at the end of a 10-second proton pulse is 40% instead of 1% without the peptide) (PubMed:28396446). It shows a lower affinity for ASIC3 than CNF-Tx1.1 (PubMed:28396446). In vivo, intramuscular injection into mice enhances acid-induced muscle pain (Probable). CNF-Tx1.3: Potentiates ASIC3 (homotrimer) currents (PubMed:28396446) and heterotrimer-containing ASIC3 (Probable). Is less potent than CNF-Tx1.1 and CNF-Tx1.2 (PubMed:28396446). In addition, it slows the desensitization kinetics of ASIC3 (Probable). In vivo, intramuscular injection into mice enhances acid-induced muscle pain (Probable). Expressed by the venom duct. The amidation of Phe-8 is essential for rat ASIC3 current potentiation. A synthetic peptide with Phe-8 not amidated does not potentiate ASIC3 current. Belongs to the NPY family.