2024-03-29T08:01:20Zhttp://digital.csic.es/dspace-oai/requestoai:digital.csic.es:10261/670312019-03-07T11:38:53Zcom_10261_54com_10261_1col_10261_307
Slow intrinsic spikes recorded in vivo in rat CA1-CA3 hippocampal pyramidal neurons
Núñez Molina, Ángel
García-Austt, E.
Buño, Washington
The membrane potential of 45 CA1-CA3 hippocampal pyramidal cells was recorded in curarized and urethanized rats. Two slow spike types were observed together with the usual Na+ type action potential. Slow spikes were termed HTS and LTS because they were essentially identical to the high and low threshold Ca2+ spikes observed in vitro and probably represent the same kinds of activities. LTS and HTS (22 and 29 cells, respectively) were triggered at potentials ≥ 65 mV and ≤ 55 mV, had mean durations of 23.7 and 90.4 ms and mean amplitudes of 11.5 and 39.3 mV, respectively, and fired an overriding burst of the action potentials. LTS and HTS were sometimes present in the same neuron (n = 16). Depolarizing pulses triggered rhythmic HTS at rates that increased with depolarization up to a 5 impulses/s maximum. The same limit was found with imposed membrane potential sine currents at frequencies within the θ rhythm range. With spontaneous or imposed hyperpolarizations LTS were evoked by depolarizing, at the break of hyperpolarizing pulses, or spontaneously. They were also evoked at the depolarizing, or recovery, slopes of inhibitory postsynaptic potentials. HTS and LTS supply pyramidal neurons with different firing patterns which enhance the system's integrative possibilities. Evidence is provided that θ is not exclusively generated by network properties, since rhythmic HTS may participate.
Peer Reviewed
2013-02-20T12:25:31Z
2013-02-20T12:25:31Z
1990
2013-02-20T12:25:31Z
artículo
http://purl.org/coar/resource_type/c_6501
Experimental Neurology 109: 294- 299 (1990)
0014-4886
http://hdl.handle.net/10261/67031
en
none
Academic Press