- Urinary bladder hyporeflexia and reduced pain-related behaviour in P2X3-deficient mice. Cockayne, D.A., Hamilton, S.G., Zhu, Q.M., Dunn, P.M., Zhong, Y., Novakovic, S., Malmberg, A.B., Cain, G., Berson, A., Kassotakis, L., Hedley, L., Lachnit, W.G., Burnstock, G., McMahon, S.B., Ford, A.P. Nature (2000)