Responses of vomeronasal neurons to natural stimuli

The vomeronasal organ (VNO) of mammals plays an essential role in the detec tion of pheromones, We obtained simultaneous recordings of action potential s from Large subsets of VNO neurons. These cells responded to components of urine by increasing their firing rate. This chemosensory activation requir ed phospholipase C function. Unlike most other sensory neurons, VNO neurons did not adapt under prolonged stimulus exposure, The full time course of t he VNO spiking response is captured by a simple quantitative model of ligan d binding. Many individual VNO neurons were strongly selective for either m ale or female mouse urine, with the effective concentrations differing as m uch as a thousandfold. These results establish a framework for understandin g sensory coding in the vomeronasal system.