Central action of prosaptide TX14(A) against gp120-induced allodynia in rats

We investigated the effect of the prosaposin-derived peptide prosaptide TX14(A) on tactile allodynia in rats following intraplantar injection of the HIV envelope glycoprotein gp120. Systemic administration of TX14(A) dose-dependently prevented onset of tactile allodynia following intraplantar injection of gp120 and also transiently alleviated established allodynia in the same model. TX14(A) did not prevent tactile allodynia when injected directly into the foot pad whereas intrathecal administration of TX14(A) both prevented and alleviated gp120-induced tactile allodynia. Nerve and spinal cord levels of TNFα protein were unchanged in intraplantar gp120 injected rats that displayed allodynia. These results indicate that TX14(A) has anti-allodynic properties in a rat model of gp120-induced tactile allodynia and that the mechanism of action of TX14(A) may include modulation of spinal nociceptive processing.