Khasabov SG, Simone DA (2013) Loss of neurons in rostral ventromedial medulla that express neurokinin-1 receptors decreases the development of hyperalgesia. Neuroscience 250C:151-165. doi: 10.1016/j.neuroscience.2013.06.057
Summary: Previous data has indicated that neurokinin-1 receptors are located on ON cells in the rostral ventromedial medulla (RVM). ON cells are considered pronociceptive because noxious stimulation is stimulatory. In this work the authors eliminated ON cells using 0.3-μl injections of 1 μM SSP-SAP (Cat. #IT-11) into the left and right side of the RVM. Blank-SAP (Cat. #IT-21) was used as a control. SSP-SAP treatment did not change mechanical or heat withdrawal responses, or change morphine-induced analgesia. A significant reduction in the duration of nocifensive behaviors induced by various hyperalgesic stimulators indicated that these neurons are involved in pain facilitation rather than modulation.