To examine the role of NMBR+ dorsal horn neurons in itch and pain transmission, the authors treated mice with NMB-SAP (Cat. #IT-70; 2–3 μg, i.t.) at which no side effects were observed. NMB-SAP treated mice barely showed scratching behaviors, whereas control mice exhibited NMB-induced scratching with a rapid onset of scratching responses. These data demonstrate an important role of NMBR+ neurons in itch transmission. In contrast to notable deficits in itch transmission, NMB-SAP treated mice exhibited normal behavioral responses to acute mechanical stimuli, thermal stimuli and tail immersion. The authors also examined inflammatory pain behaviors of NMB-SAP treated mice and found normal nocifensive behaviors.
Wan, L., H. Jin, X.-Y. Liu, J. Jeffry, D.M. Barry, K.-F. Shen, J.-H. Peng, X.-T. Liu, J.-H. Jin, Y. Sun, R. Kim, Q.-T. Meng, P. Mo, J. Yin, A. Tao, R. Bardoni, and Z.-F. Chen, Distinct roles of NMB and GRP in itch transmission. Scientific Reports, 2017. 7(1): p. 15466.
NMB-SAP (Cat. #IT-70) is a tool for eliminating cells that express Neuromedin B receptor; targeted via Neuromedin B, eliminated via saporin. Neuromedin B (NMB) and GRP are two members of the mammalian bombesin family of peptides. These two peptides activate structurally similar but pharmacologically distinct G-protein-coupled receptors. NMB is expressed in a subset of sensory neurons that co-label with calcitonin gene-related peptide and TRPV1, suggestive of a role for NMB in nociception. In the periphery, NMB and GRP have a wide variety of actions including smooth muscle contraction and exocrine and endocrine functions. In the CNS these peptides regulate food intake and body temperature, as well as stress behavioral responses.
NMB-SAP eliminates Neuromedin B receptor expressing cells. All other cells are left untouched. It is not suitable for retrograde transport.