The Nitric Oxide/cGMP Pathway Tunes the Thermosensitivity of Swimming Motor Patterns in Xenopus laevis Tadpoles

摘要: We investigated the role of nitric oxide (NO)/cGMP pathway in setting thresholds for failure and recovery during hyperthermic stress swimming central pattern generator immobilized Xenopus tadpoles (stage 42). recorded motor patterns induced by tail skin stimulation (TS) (1 ms current pulse) or bath application 50 microm NMDA. Swimming rhythm frequency increased a linear manner with increasing temperature. In presence NO donor S-nitroso-N-acetylpenicillamine (SNAP), from was greatly slowed, often taking longer than duration experiment. Pharmacological activation NO/cGMP using SNAP 8-bromo-cGMP (1) decreased TS-evoked swim episodes; (2) temperature threshold circuit failure; (3) at which recovered; (4) time taken to recover. inhibition scavenger CPTIO, synthase (NOS) inhibitor L-NAME guanylyl cyclase ODQ (1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one) had opposite effects. NMDA rhythms were more resistant episodes, but effects on sensitivity evoked similar those swimming, suggesting that drug occur pattern-generating networks rather sensory pathways. conclude is involved temperatures subsequent fictive tadpoles, we suggest this part variable response prevent overexcitation abiotic under different environmental conditions.