title: Influence of calcium on the Limulus photoreceptor potential.
mesh_terms: D000818:Animals; D002118:Calcium / Q000494:pharmacology*; D004558:Electric Stimulation; D005071:Evoked Potentials / Q000187:drug effects; D006737:Horseshoe Crabs; D009474:Neurons / Q000187:drug effects; D010786:Photoreceptor Cells / Q000187:drug effects*; D012964:Sodium / Q000494:pharmacology; D014700:Verapamil / Q000494:pharmacology
chemical_list: D012964:Sodium; D014700:Verapamil; D002118:Calcium