Sandwich ELISA quantitative detection kit for Rat trkA in cell culture supernates, cell lysates and tissue homogenates.Tropomyosin receptor kinase A (TrkA) are efficacious in attenuating skeletal pain.1 TrkA mutants were able to activate signaling cascades and were even more efficient in promoting neurite outgrowth than the wild-type receptor.2 TrkA is part of a sub-family of protein kinases which includes TrkB and TrkC. Also, there are other neurotrophic factors structurally related to NGF BDNF (for Brain-Derived Neurotrophic Factor), NT-3 (for Neurotrophin-3) and NT-4 (for Neurotrophin-4). While TrkA mediates the effects of NGF, TrkB is bound and activated by BDNF, NT-4, and NT-3. Further, TrkC binds and is activated by NT-3.3 TrkA receptor was found in keratoconus-affected corneas, along with an increased level of repressor isoform of Sp3 transcription factor.4 The standard product used in this kit is extracellular part (A33-P418) of recombinant rat TRKA, consisting of 386 amino acids with the molecular weight of 69kD.