Effects of extracellular ATP on survival of sensory neurons in the dorsal root ganglia of rats

Abstract

ATP was added to the cultured sensory neurons obtained from the dorsal root ganglia of the neonatal rats and PBS was added to serve as control. MTT assays were conducted to evaluate the survival and activity of the cultured neurons. And the silicone regenerative chamber was used after the sciatic nerve incision of the mature SD rat. 1 mmol/L ATP was injected into the left chamber and 0. 09 % natrium chloride was injected into the right chamber as controls. The changes of nitric oxide synthase (NOS) activity in the corresponding dorsal root ganglia were measured histochemically and image analysis was also performed 4 days after the sciatic nerve injury. The results showed that extracellular ATP could enhance the survival of the neurons and the number of NOS positive neurons were significantly different between the ATP and control groups (P<0. 05). It was suggested that extracellular ATP had neurotrophic effect on neurons survival and could inhibit the NOS activity of the sensory neurons after the peripheral nerve incision, hence exerting the protective effect on the neurons, which was valuable for nerve regeneration after nerve injury.

Keywords

extracellular ATP / neurotrophins / neurons / nitric oxide synthase / Sprague-Dawley rats

References

[1] Van EldikL. Neurotrophic activity of S-100B in cultures of dorsal root ganglia from embryonic chick and fetal rat. Brain Res, 1991, 524: 280-280

[2] NearyJ T, RathboneM P, CattabeniF, et al.. Trophic actions of extracellular nucleotides and nucleosides on glial and neuronal cells. Trends Neurosci, 1996, 19: 13-13

[3] StoneT W. Purines and receptors. TiNS, 1998, 21: 16-16

[4] IkeuchiY, NishizakiT. ATP-regulated K channel and cytosolic Ca²⁺ mobilization in cultured rat spinal neurons. Eur J Pharmcol, 1996, 302: 163-163

[5] GuY, SpasicZ, WuW. The effects of remaining axons on motoneuron survival and NOS expression following axotomy in the adult rat. Dev Neurosci, 1997, 19(3): 255-255

[6] DawsonV L, DawsonT M. Nitric oxide in neuronal degeneration. Proc Soc Exp Biol Med, 1996, 211: 33-33

[7] ShibutaS, KosakaJ, MashimoT, et al.. Nitric oxide-induced cytotoxicity attenuation by thiopentone sodium but not pentobarbitone sodium in primary brain cultures. Br J Pharmacology, 1998, 124: 804-804