Olfaction Plasticity and Neuropeptides

New study shows that a pheromone neprilysin is important for olfactory plasticity in worms and reflects behaviors of attraction and dispersal. While this may be species specific, one might ponder if the mechanims are similar in higher organisms. In any event, this class of neuropeptides have influence on a variety of physiological processes.

Cohen writes "NEP expression is modulated by various factors, including interferon, interleukin (IL)-1, tumor necrosis factor (TNF), IL-4 and glucocorticoids. Tobacco smoke has been reported to inactivate NEP in vitro and in an animal model, but studies in humans have not demonstrated a clear difference in NEP activity between smokers and nonsmokers. Genetic variation in NEP could account for some of the wide variation observed in humans. Mice homozygous for NEP null mutations are surprisingly normal but do exhibit decreased blood pressure, increased microvascular permeability, and increased susceptibility to endotoxin shock. The hypothesis that genetic variation in NEP expression may cause differences in susceptibility to disorders such as bronchopulmonary dysplasia, lung cancer, asthma, and sepsis, in which neuropeptides have been implicated, remains untested but attractive."

American Journal of Respiratory Cell and Molecular Biology, Vol. 21, No. 1. (1999) http://www.citeulike.org/user/HEIRS/article/8027099

Science, Vol. 329, No. 5999. (24 September 2010), pp. 1647-1650. http://www.citeulike.org/user/HEIRS/article/8025793