Doublet of action potentials evoked by intracellular injection of current into rat motoneurones

• Autorzy: Mrowczynski W. , Krutki P. , Celichowski J.
• Języki publikacji: EN

Abstrakty

EN

Experiments were based on electrophysiological method of direct stimulation and recording from motoneurones located in L4–L5 segments of the rats spinal cord. Records from spontaneously fi ring motoneurones were collected after intracellular application of a current of gradually increasing intensity. Current threshold for generation of the fi rst action potential was determined. Additionally, intervals between six fi rst potentials were analyzed. It was demonstrated that the gradually increasing current intensity caused the generation of doublets in 68% of motoneurones studied. Doublets appeared when stimulating current increased to 120–500% of the threshold value. Moreover, the appearance of the doublet resulted in a signifi cant prolongation of time interval to the subsequent, third action potential. These results suggest that doublets in motoneuronal fi ring appear as a result of their strong synaptic excitation. The prolonged interpulse interval after the doublet fi ring can be due to an increase of duration and amplitude of afterhyperpolarization (AHP), previously observed in antidromic doublet stimulation.

• Wydawca: -
• Czasopismo: Acta Neurobiologiae Experimentalis
• Rocznik: 2009
• Tom: 69
• Numer: 3
• Opis fizyczny: p.328

Twórcy

autor

Mrowczynski W.

• Department of Neurobiology, University School of Physical Education in Poznan, Poznan, Poland

autor

Krutki P.

• Department of Neurobiology, University School of Physical Education in Poznan, Poznan, Poland

autor

Celichowski J.

• Department of Neurobiology, University School of Physical Education in Poznan, Poznan, Poland