Multiple Neurokinin Receptors in the Rat Lower Urinary Tract

In recent years huge evidence has accumulated indicating that neuropeptides are widely distributed in the lower urinary tract of various animal species(l). The aim of this study was to determine the relative ability of neurokinins (subs tance P, SP; neurokinin A, NKA; neurokinin B, NKB) and tachykinins (kassinin, KASS; eledoisin, ELE; physalaemin, PHYS) to activate motility and produce plasma extravasation in the rat lower urinary tract. The effects of neurokinins (NKs) and tachykinins (TKs) were compared to those of capsaicin, a drug known to stimulate neuropeptide release from primary afferent fibers (2).