Effects of 20,000 EU of Clinical Center Reference Endotoxin (CCRE) Versus Placebo(ENDOHEART)

To determine the systemic inflammatory effects of inhaled endotoxin and associated alterations in cardiovascular function. Subjects will undergo an exposure to inhaled endotoxin in a crossover fashion with normal saline inhalation. Blood samples and sputum samples will be taken before and after inhalation challenge to measure markers of systemic inflammation. Cardiovascular measures, including a heart rate variability monitor, flow mediated dilation of the brachial artery and left ventricular stain will also be measured.