Roma Kalra

Immunosuppressive and Anti-Inflammatory Effects of Nicotine Administered by Patch in an Animal Model

ABSTRACT To study the immunological effects of nicotine, there are several rodent models for chronic nicotine administration. These models include subcutaneously implanted miniosmotic pumps, nicotine-spiked drinking water, and self-administration via jugular cannulae. Administration of nicotine via these routes affects the immune system. Smokers frequently use nicotine patches to quit smoking, and the immunological effects of nicotine patches are largely unknown. To determine whether the nicotine patch affects the immune system, nicotine patches were affixed daily onto the backs of Lewis rats for 3 to 4 weeks. The patches efficiently raised the levels of nicotine and cotinine in serum and strongly inhibited the antibody-forming cell response of spleen cells to sheep red blood cells. The nicotine patch also suppressed the concanavalin A-induced T-cell proliferation and mobilization of intracellular Ca2+ by spleen cells, as well as the fever response of animals to subcutaneous administration of turpentine. Moreover, immunosuppression was associated with chronic activation of protein tyrosine kinase and phospholipase C-γ1 activities. Thus, in this animal model of nicotine administration, the nicotine patch efficiently raises the levels of nicotine and cotinine in serum and impairs both the immune and inflammatory responses.

Response of F344 rats to inhalation of subclinical levels of sarin: exploring potential causes of Gulf War illness

Subclinical, repeated exposures of F344 rats to sarin resulted in brain alterations in densities of chlonergic receptor subtypes that may be associated with memory loss and cognitive dysfunction. The exposures also depressed the immune system. The rat appears to be a good model for studying the effects of subclinical exposure to a nerve gas.