By implication, it would appear that circulating epithelial progenitor cells most likely do play an important role in airway repair, although whether this is a direct of indirect effect still needs to be established. Ultimately, infection is critical and is an area of active investigation in the lab. In summary, CK5 expressing circulating epithelial progenitor cells are present in circulation in normal human subjects and can be quantified with the real time PCR assay that we have established. Furthermore,Brivudine the circulating epithelial progenitor cells are significantly reduced immediately after lung transplantation, and then increase with time as lung function improves. We suggest that circulating epithelial progenitor cells may play an important role in airway repair after lung transplantation. In addition, circulating epithelial progenitor cells may be used as a biomarker of airway repair. Cocaine is a plant alkaloid derived from coca plant leaves and represents a major drug of abuse. In animal models, acute administration of cocaine evokes changes in locomotor activity, grooming, and feeding, and can induce uncontrolled repetitive behaviors. At the cellular level, cocaine elevates extracellular monoamine levels by inhibiting monoamine reuptake transporters, including DAT, SERT and NET. By acting on their cognate receptors, monoamines elicit both short-term and long-lasting alterations in the nervous system, which ultimately lead to the development of drug dependence. While dopamine is generally believed to be a principal neurotransmitter functioning in the mesolimbic dopamine system to mediate drug dependence, ample evidence suggests that other neurotransmitter systems are also required for the expression of drug addiction behaviors. In particular,Cefotiam hydrochloride serotonin is believed to play an important role in mediating the reinforcing effects of cocaine. For example, the induction of conditioned place preference by cocaine is normal in DAT knockout mice, but is eliminated in mice lacking both DAT and SERT. Further, it has been shown that that DAT knockout mice can still self-administer cocaine, though a recent study has challenged this finding. Therefore, to better understand the mechanistic underpinnings of drug addiction, and to develop new therapeutic interventions, a greater knowledge of the genes and molecules regulating cocaine’s behavioral effects is required. Despite their simplicity, invertebrate model organisms such as C. elegans and Drosophila are widely used in neurobiology and have yielded novel insights into relatively complex behavioral phenomena, including drug dependence. Furthermore, the major genes found to be involved in drug dependence are conserved in these organisms. The powerful genetics of invertebrate models, combined with their short generation time, make these organisms a valuable resource for the study of basic mechanisms underlying drug-induced behaviors. In the present study, we tested the effect of cocaine on C. elegans locomotion behavior. We find that acute cocaine treatment alters its locomotor activity. This behavioral response to cocaine is mediated by serotonin. In this study, we have shown that C. elegans responds to acute cocaine treatment by reducing locomotor activity, a behavioral response that is mediated by the neurotransmitter serotonin.