Reversal of thermal hyperalgesia in a rat partial sciatic nerve ligation model by Prosaptide TX14(A).

We used the partial sciatic nerve ligation (PSL) model of Seltzer to assess thermal hyperalgesia after administration of Prosaptide 14-mer, TX14(A). At a dose of 200 microg/kg in Wistar rats, subcutaneous delivery of TX14(A) reversed thermal hyperalgesia at 3 and 24 h. Values declined at 48 h and returned to baseline at 72 h. A dosing study of TX(14)A gave a dependent response with 100 microg/kg having a similar potency to the 200 microg/kg study with 50 and 10 microg/kg responding somewhat lower. When TX(14)A was administered every fourth day for 12 days at 100 microg/kg, 24 h post injection values returned to baseline each time. Our results suggest that Prosaptide may have potential for therapeutic use in neuropathic pain syndromes in humans.