[Synaptic excitation of reticulospinal neurons during the startle reaction in cats anesthetized with chloralose].
Synaptic processes in the bulbar and pontine reticulospinal neurons (RS-neurons) were studied in chloralose-anesthetized cats during startle reaction to somatic stimulation ("spino-bulbo-spinal"--SBS-reflex). Excitatory PSPs were found to be a main type of synaptic responses in the RS-neurons; they were oligosynaptic (including monosynaptic) and polysynaptic. The comparison between synaptic responses of RS-neurons and SBS-reflexes showed that the polysynaptic EPSPs were most effective in generation of a SBS descending volley. It was also shown that about half of bulbar and pontine RS-neurons were simultaneously involved in suprasegmental relay of the SBS-reflexes. Conduction velocities in their axons ranged between 30 and 98 m/s (mean 64.5 +/- 16.5 m/s). Some functional features of the reticular centre of startle reaction are discussed.
D000768:Anesthesia, General; D000818:Animals; D002415:Cats; D002698:Chloralose; D005116:Extrapyramidal Tracts / Q000502:physiology*; D008564:Membrane Potentials; D011930:Reaction Time / Q000502:physiology; D013216:Reflex, Startle / Q000502:physiology*; D012154:Reticular Formation / Q000502:physiology*; D013116:Spinal Cord / Q000502:physiology*; D013569:Synapses / Q000502:physiology; D009435:Synaptic Transmission
D002698:Chloralose
Sinapticheskoe vozbuzhdenie retikulo-spinal'nykh neĭronov pri osushchestvlenii reaktsii vzdragivaniia u koshek narkotizirovannykh khloralozoĭ.