{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,6]],"date-time":"2026-10-06T20:18:54Z","timestamp":1791317934876,"version":"4.3.1"},"reference-count":0,"publisher":"Wiley","issue":"1","license":[{"start":{"date-parts":[[1985,9,1]],"date-time":"1985-09-01T00:00:00Z","timestamp":494380800000},"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":[[1985,9]]},"abstract":"<jats:p>The large B cells of bull\u2010frog sympathetic ganglia are well known to be depolarized by slow synaptic transmission, muscarinic agonists, analogues of luteinizing hormone\u2010releasing hormone (LHRH), and substance P. Voltage\u2010clamp analysis shows that these actions result from two underlying mechanisms: inhibition of the M\u2010current, a voltage\u2010dependent potassium current; and in some cells, an inward current associated with an increase in conductance. The additional inward current appears as a voltage\u2010insensitive change in the instantaneous conductance (i.e. apparent leak conductance). The additional inward current is typically slower in onset and offset than is M\u2010current inhibition. It is typically seen for higher concentrations and longer durations of agonist application. In many cells, only a decrease in M\u2010current can be demonstrated. Muscarine inhibits the M\u2010current with 50% inhibition (I50) at 0.7 microM. At least 86% of the M\u2010current is muscarine sensitive. At comparable concentrations, oxotremorine produces less M\u2010current inhibition than does muscarine. Some analogues of teleost LHRH (T\u2010LHRH) are more potent as M\u2010current inhibitors than T\u2010LHRH itself. Those peptides tend to act more slowly than T\u2010LHRH. Substance P shows variable potency for M\u2010current inhibition, with I50 s ranging from 2 nM to greater than 2 microM on different cells. The response to long applications of substance P desensitizes in some cells, which has not been observed for comparable applications of muscarinic or LHRH agonists. Other tachykinins (including substance K) inhibit the M\u2010current. C\u2010terminal fragments of substance P are ineffective, and M\u2010current inhibition by substance P is not blocked by [D\u2010Pro2,D\u2010Trp7,9]\u2010 or [D\u2010Arg1,D\u2010Pro2, D\u2010Trp7,9,Leu11] substance P. The slow muscarinic excitatory post\u2010synaptic potential (e.p.s.p.) produces a graded inhibition of up to 90% of the M\u2010current. Occasional cells show an additional inward current with an associated increase in conductance during the slow e.p.s.p. This effect is less marked than with exogenous muscarinic agonists. The late, slow e.p.s.p., which is produced by stimulation of high threshold C\u2010fibre inputs and is resistant to cholinergic antagonists, also involves M\u2010current inhibition. An additional inward current can be observed in some cells. M\u2010current inhibition (by agonists or slow synaptic potentials) increases the number of spikes produced by a given depolarizing current, often allowing maintained firing. This action is not mimicked by equivalent depolarization, and is still seen when the cell is manually clamped to the original resting potential.(ABSTRACT TRUNCATED AT 400 WORDS)<\/jats:p>","DOI":"10.1113\/jphysiol.1985.sp015785","type":"journal-article","created":{"date-parts":[[2014,12,19]],"date-time":"2014-12-19T06:45:49Z","timestamp":1418971549000},"page":"63-87","source":"Crossref","is-referenced-by-count":81,"title":["Muscarinic and peptidergic excitation of bull\u2010frog sympathetic neurones."],"prefix":"10.1113","volume":"366","author":[{"given":"S W","family":"Jones","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"311","published-online":{"date-parts":[[1985,9]]},"container-title":["The Journal of Physiology"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/api.wiley.com\/onlinelibrary\/tdm\/v1\/articles\/10.1113%2Fjphysiol.1985.sp015785","content-type":"unspecified","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/physoc.onlinelibrary.wiley.com\/doi\/pdf\/10.1113\/jphysiol.1985.sp015785","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2023,10,20]],"date-time":"2023-10-20T06:32:55Z","timestamp":1697783575000},"score":1,"resource":{"primary":{"URL":"https:\/\/physoc.onlinelibrary.wiley.com\/doi\/10.1113\/jphysiol.1985.sp015785"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[1985,9]]},"references-count":0,"journal-issue":{"issue":"1","published-print":{"date-parts":[[1985,9]]}},"alternative-id":["10.1113\/jphysiol.1985.sp015785"],"URL":"https:\/\/doi.org\/10.1113\/jphysiol.1985.sp015785","archive":["Portico"],"relation":{},"ISSN":["0022-3751","1469-7793"],"issn-type":[{"value":"0022-3751","type":"print"},{"value":"1469-7793","type":"electronic"}],"subject":[],"published":{"date-parts":[[1985,9]]}}}