For all studies, the investigators will recruit healthy male volunteers between the ages of 18 and 64 years. Subjects will be non-smokers on no concomitant medications. Individuals with clinically significant co-morbidity such as heart failure, hypertension, hyperlipidaemia, diabetes mellitus, asthma, coagulopathy or bleeding disorders will be excluded. Exclusion criteria will also include those individuals who have had recent infective or inflammatory conditions or recently donated blood (within the last 3 months).