Pentraxins are a family of proteins emerging from genes that are conserved in their carboxy-terminal halves a pentraxin domain and are prototypical acute phase proteins with acquired novel amino-terminal domains. Pentraxins, include C reactive protein (CRP) and Serum Amyloid P component (SAP), which serve as indicators of inflammatory reactions as a result of the exposure of liver cells to cytokines, mainly interleukin-6 (IL-6). Neuronal Pentraxins: A new family of putative integral membrane pentraxins or Neuronal pentraxins identified through interaction with a presynaptic snake venom toxin taipoxin. NPX1, NPX2 and NPXR (Neuronal Pentraxin Receptor), the three neuronal pentraxins represent a novel neuronal uptake pathway that may function during synapse formation and remodeling. The N-terminal half of neuronal pentraxins are 20-30% identical to previously identified pentraxins (CRP and SAP), the three neuronal pentraxins are 50% identical to each other and are significantly larger than the classical pentraxins (>50 versus 30kDa), suggesting that they may have additional novel functions. NPX2 (Neuronal Pentraxin 2), 429aa in mouse, 432 in rat and 431 in human (chr 7q21), mainly expressed in brain, pancrease, liver and testis. It is likely to play role in the modification of cellular properties that underlie long-term plasticity. NPX1, NPX2 has potential N-linked glycosylation sites.