Validated assays for the determination of gemcitabine in human plasma and urine using high-performance liquid chromatography with ultraviolet detection.

Procedures are described for the determination of gemcitabine, a new anti-tumor agent, and its uridine metabolite in human plasma and in human urine. The sample preparation for the plasma assay involves precipitation of plasma proteins with isopropanol and ethyl acetate. Following this, the solids are discarded and the supernatant is evaporated to dryness.

Disposition in humans of racemic picenadol, an opioid analgesic.

Racemic picenadol is being tested clinically as an analgesic. The (+)-enantiomer of picenadol is an opioid agonist and the (-)-enantiomer is a weak agonist/antagonist. The disposition of racemic [14C] picenadol was studied in healthy men after a single dose was administered im (N = 3) and orally (N = 5).

Physiologic disposition of pergolide.

Pergolide, a synthetic ergoline, is a potent long-acting dopaminergic drug effective in Parkinson's disease and amenorrhea-galactorrhea. After 138 micrograms 14C-pergolide orally to healthy subjects, radioactivity was present in plasma and red blood cells. Salivary radioactivity was one third to one tenth that in plasma.

The relationship between blood levels and dose of methylmercury in man.

The kinetics of blood deposition and clearance of methylmercury were measured in volunteers given a single meal of fish containing 18 to 22 microgram mercury/kg body weight. Peak blood concentrations were achieved within 4 to 14 hr. Disappearance from blood was biphasic, with average half-times of 7.

The disposition of l-3-[(dimethylamino)-(m-dioxan-5-yl)methyl]pyridine in man.

l-3-[(Dimethylamino)-(m-dioxan-5-yl)methyl]pyridine hydrochloride (LY 108380) is being evaluated in man as a potentially useful, nonaddicting analgesic agent. This substituted dioxane is structurally different from any currently known analgesic. Following im administration of the 14C-labeled compound to healthy volunteers, the drug was absorbed rapidly (t1/2(abs) = 2--20 min).