Does low-threshold electrical stimulation of muscle afferent fibers affect expression of the pool of neurotrophin 3 in the lumbar spinal cord of the rat?

• Autorzy: Gajewska O. , Piasecka J. , Kasicki S. , Skup M. , Czarkowska-Bauch J.
• Języki publikacji: EN

Abstrakty

EN

Availability of brain-derived neurotrophic factor (BDNF) and neurotrophin 4 (NT-4) in the nervous system depends on the neuronal activity. We have previously shown that moderate locomotor exercise causes an increase of BDNF and NT-4 proteins but not neurotrophin 3 (NT-3) in the lumbar spinal cord. The questions arise whether NT-3 is regulated in a different way than BDNF and NT-4 or, that proprioceptive stimulation during treadmill locomotion is not sufficient to activate NT-3? To verify the latter possibility we applied direct electrical stimulation of the tibial nerve to activate the low-threshold muscle afferent fibers eliciting monosynaptic Hoffmann (H) reflex, an analog of the stretch reflex. Both the H-reflex and direct motor response (M), recorded from the soleus muscle, allowed keeping the strength of stimulus near the threshold of M response, confirming that stimulus is primarily addressed to lowthreshold afferents. The cuff stimulating electrode over the nerve and recording intramuscular electrodes were implanted bilaterally. The tibial nerve was stimulated unilaterally, throughout one and four weeks, starting two weeks after implantation of electrodes. The contralateral limb served as a control. Two sessions of stimulation daily, 30 min each (rectangular pulse of 300 µs duration at 0.33 Hz) were separated by about 2 h break. The total number of stimuli delivered was about 800 per day. The expression of NT-3 in the spinal cord was evaluated immunohistochemically (IR, Santa Cruz antibody) in the lumbar L4/L5 segments. Both neuropil and numerous cell bodies expressed NT-3. Perikaryonal expression was predominantly observed in the lower dorsal horn laminae (III- VI), in the intermediate zone and in the lamina IX. However, the effects of implantation and stimulation on the expression of NT-3 was negligible. The effect will be verified quantitatively with Elisa method. Supported by MSE grant N N401 0480 33.

• Wydawca: -
• Czasopismo: Acta Neurobiologiae Experimentalis
• Rocznik: 2011
• Tom: 71
• Numer: 1
• Opis fizyczny: p.166

Twórcy

autor

Gajewska O.

• Nencki Institute of Experimental Biology, Warsaw, Poland

autor

Piasecka J.

• Nencki Institute of Experimental Biology, Warsaw, Poland

autor

Kasicki S.

• Nencki Institute of Experimental Biology, Warsaw, Poland

autor

Skup M.

• Nencki Institute of Experimental Biology, Warsaw, Poland

autor

Czarkowska-Bauch J.

• Nencki Institute of Experimental Biology, Warsaw, Poland