title: Rectangular fluctuations in potential of the afferent nerve terminal during depolarization in the frog muscle spindle.
abstract: Rectangular fluctuations in potential are observed during application of depolarizing currents from 1.5 to 6.3 nA across the air-gap on which the myelinated segment just outside the capsule in isolated muscle spindles is laid. The rapid decay in the potential is often triggered by after-hyperpolarization following afferent discharges. The fluctuations are not affected by TTX or in Na+-free solution but are reversibly blocked by 100 microM quinine. The results suggest that the fluctuations may be due to [Ca2+]i-activated Pk.
mesh_terms: D000200:Action Potentials / Q000187:drug effects; D000344:Afferent Pathways / Q000187:drug effects / Q000502:physiology*; D000818:Animals; D002118:Calcium / Q000494:pharmacology; D009132:Muscles / Q000294:innervation*; D011803:Quinine / Q000494:pharmacology; D011898:Ranidae; D012964:Sodium / Q000494:pharmacology; D013779:Tetrodotoxin / Q000494:pharmacology
chemical_list: D013779:Tetrodotoxin; D012964:Sodium; D011803:Quinine; D002118:Calcium