{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,8]],"date-time":"2026-10-08T20:02:21Z","timestamp":1791489741961,"version":"4.3.4"},"reference-count":0,"publisher":"Wiley","issue":"1","license":[{"start":{"date-parts":[[1987,4,1]],"date-time":"1987-04-01T00:00:00Z","timestamp":544233600000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/onlinelibrary.wiley.com\/termsAndConditions#vor"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["The Journal of Physiology"],"published-print":{"date-parts":[[1987,4]]},"abstract":"<jats:p>1. The repolarization of the action potential, and a fast after\u2010hyperpolarization (a.h.p.) were studied in CA1 pyramidal cells (n = 76) in rat hippocampal slices (28\u201037 degrees C). Single spikes were elicited by brief (1\u20103 ms) current pulses, at membrane potentials close to rest (\u201060 to \u201070 mV). 2. Each action potential was followed by four after\u2010potentials: (a) the fast a.h.p., lasting 2\u20105 ms; (b) an after\u2010depolarization; (c) a medium a.h.p., (50\u2010100 ms); and (d) a slow a.h.p. (1\u20102 s). Both the fast a.h.p. and the slow a.h.p. (but not the medium a.h.p.) were inhibited by Ca2+\u2010free medium or Ca2+\u2010channel blockers (Co2+, Mn2+ or Cd2+); but tetraethylammonium (TEA; 0.5\u20102 nM) blocked only the fast a.h.p., and noradrenaline (2\u20105 microM) only the slow a.h.p. This suggests that two Ca2+\u2010activated K+ currents were involved: a fast, TEA\u2010sensitive one (IC) underlying the fast a.h.p., and a slow noradrenaline\u2010sensitive one (IAHP) underlying the slow a.h.p. 3. Like the fast a.h.p., spike repolarization seems to depend on a Ca2+\u2010dependent K+ current of the fast, TEA\u2010sensitive kind (IC). The repolarization was slowed by Ca2+\u2010free medium, Co2+, Mn2+, Cd2+, or TEA, but not by noradrenaline. Charybdotoxin (CTX; 30 nM), a scorpion toxin which blocks the large\u2010conductance Ca2+\u2010activated K+ channel in muscle, had a similar effect to TEA. The effects of TEA and Cd2+ (or Mn2+) showed mutual occlusion. Raising the external K+ concentration reduced the fast a.h.p. and slowed the spike repolarization, whereas Cl\u2010 loading of the cell was ineffective. 4. The transient K+ current, IA, seems also to contribute to spike repolarization, because: (a) 4\u2010aminopyridine (4\u2010AP; 0.1 mM), which blocks IA, slowed the spike repolarization; (b) depolarizing pre\u2010pulses, which inactivate IA, had a similar effect; (c) hyperpolarizing pre\u2010pulses speeded up the spike repolarization; (d) the effects of 4\u2010AP and pre\u2010pulses persisted during Ca2+ blockade (like IA); and (e) depolarizing pre\u2010pulses reduced the effect of 4\u2010AP. 5. Pre\u2010pulses or 4\u2010AP broadened the spike less, and in a different manner, than Ca2+\u2010free medium, Cd2+, Co2+, Mn2+, TEA or CTX. The former broadening was uniform, with little effect on the fast a.h.p., whereas the latter affected mostly the last two\u2010thirds of the spike repolarization and abolished the fast a.h.p.(ABSTRACT TRUNCATED AT 400 WORDS)<\/jats:p>","DOI":"10.1113\/jphysiol.1987.sp016517","type":"journal-article","created":{"date-parts":[[2014,12,19]],"date-time":"2014-12-19T06:41:54Z","timestamp":1418971314000},"page":"733-759","source":"Crossref","is-referenced-by-count":562,"title":["Action potential repolarization and a fast after\u2010hyperpolarization in rat hippocampal pyramidal cells."],"prefix":"10.1113","volume":"385","author":[{"given":"J F","family":"Storm","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"311","published-online":{"date-parts":[[1987,4]]},"container-title":["The Journal of Physiology"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/api.wiley.com\/onlinelibrary\/tdm\/v1\/articles\/10.1113%2Fjphysiol.1987.sp016517","content-type":"unspecified","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/physoc.onlinelibrary.wiley.com\/doi\/pdf\/10.1113\/jphysiol.1987.sp016517","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2023,10,21]],"date-time":"2023-10-21T09:48:30Z","timestamp":1697881710000},"score":1,"resource":{"primary":{"URL":"https:\/\/physoc.onlinelibrary.wiley.com\/doi\/10.1113\/jphysiol.1987.sp016517"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[1987,4]]},"references-count":0,"journal-issue":{"issue":"1","published-print":{"date-parts":[[1987,4]]}},"alternative-id":["10.1113\/jphysiol.1987.sp016517"],"URL":"https:\/\/doi.org\/10.1113\/jphysiol.1987.sp016517","archive":["Portico"],"relation":{},"ISSN":["0022-3751","1469-7793"],"issn-type":[{"value":"0022-3751","type":"print"},{"value":"1469-7793","type":"electronic"}],"subject":[],"published":{"date-parts":[[1987,4]]}}}