OBJECTIVETo analyze the pharmacokinetics of intraperitoneal chemotherapy with mitomycin C (MMC) bound to activated carbon particles.

METHODSA nude mouse model with transplanted human gastric cancer was established. The mice were given MMC by i.v. or intraperitoneal (i.p.) injections, or given i.p. MMC bound to activated carbon particles (MMC-CH). Pharmacokinetic assays were carried out at different time points (0.5, 1, 2, 3, 6, 12 and 24 h) in 7 mice per each time point, to compare the MMC concentrations revealed by the above mentioned methods.

RESULTSThe MMC concentration in peritoneal exudate, omentum and lymph nodes of MMC-CH group was significantly higher than that of MMC solution i.p. group and MMC i.v. group (P < 0.001). On the other hand, the MMC level in serum was significantly lower than that in two control groups (P < 0.001). High MMC level was maintained longer than 24 hours in the MMC-CH group. Intraperitoneal chemotherapy with MMC solution resulted in a low MMC concentration in serum, peritoneal exudates and lymph nodes, and only a transient high level of MMC in the omentum. After i.v. administration, a significantly higher level of MMC concentration occurred in the serum, but only a shortly increased concentration of MMC in the omentum, and lower concentration in peritoneal exudate and lymph nodes as compared with those in the other two groups (P < 0.001).

CONCLUSIONHigh concentration of MMC in peritoneal exudate, omentum and lymph nodes maintained longer than 24 hours and a significantly lower MMC serum concentration can be achieved by administration of intraperitoneal administration of MMC bound to activated carbon particles.

Animals ; Antibiotics, Antineoplastic ; administration & dosage ; pharmacokinetics ; Charcoal ; administration & dosage ; pharmacokinetics ; Female ; Humans ; Injections, Intraperitoneal ; Male ; Mice ; Mice, Inbred BALB C ; Mice, Nude ; Mitomycin ; administration & dosage ; pharmacokinetics ; Neoplasm Transplantation ; Stomach Neoplasms ; drug therapy ; metabolism ; pathology

Chronic obstructive pulmonary disease (COPD) is a type of progressive, obstructive lung disease characterized by long-term poor airflow. The symptoms of COPD may be relieved and its progression delayed by fluticasone (FTS), salmeterol (SM), and tiotropium (TTP). The aim of this study is to investigate pharmacokinetic (PK) characteristics of inhaled FTS, SM, and TTP after co-administration. An open-label, single-arm, three-period, simple ascending dose study was conducted in 10 healthy male subjects. A single dose of FTS/SM (250/50 µg) and TTP (18 µg) were concomitantly inhaled in period 1, and the dose of each drug was escalated to two- and three-fold in periods 2 and 3, respectively, with a 2-week washout between periods. Activated charcoal was co-administered before and after inhalation to block gastrointestinal absorption. Blood samples for PK analysis were collected up to 24 hours. PK parameters were obtained by non-compartmental analysis. FTS, SM, and TTP rapidly reached maximum plasma concentration after inhalation (0.08–3.00 h, 0.03–0.10 h and 0.03–0.10 h, respectively) and were eliminated with mean half-lives of 9.29–10.44 h, 6.09–12.39 h and 0.25–47.42 h, respectively. PK assessment of the lowest dose of TTP was limited due to relatively low systemic exposure compared to the lower limit of quantification. In conclusion, PK characteristics of FTS, SM, and TTP by pulmonary absorption were evaluated after concurrent inhalation. FTS and SM showed dose-proportional PK profiles between 250–750 µg and 50–150 µg, respectively, while TTP presented dose-proportionality in the early phase exposure between 18-54 µg.
Charcoal ; Fluticasone* ; Gastrointestinal Absorption ; Humans ; Inhalation* ; Lung Diseases, Obstructive ; Male ; Pharmacokinetics ; Plasma ; Pulmonary Disease, Chronic Obstructive ; Respiratory Tract Absorption ; Salmeterol Xinafoate* ; Tiotropium Bromide*

OBJECTIVETo explore toxicokinetics of tetramethylene disulphotetramine (TETS) in rabbit and the effects on toxicokinetics of TETS after activated charcoal by gavage.

METHODSEight rabbits were exposed through gavage and vein respectively, the blood samples were collected from the center artery in ear of rabbit at an arranged time. Four rabbits were exposed after being intubated into urethra and common bile duct. The samples of bile and urine were collected at arranged times. After being exposed by gavage, activated charcoal (1 g/kg) was administrated in the activated charcoal group and the distilled water (1 g/kg) administrated to the controls. The samples of blood were collected from the center artery in ear of rabbit at arranged times. The contents of TETS in samples were determined by GC/NPD method. Analysed by the 3p87 soft, toxicokinetics parameters of TETS were acquired.

RESULTSTETS was eliminated very slowly in rabbit. The plasma half time in elimination phase (Tke1/2) of TETS was 56.9 hours in vein exposure group and 262.5 hours in oral exposure group respectively. The plasma clearance (CL) of it was only 15.4 ml.kg(-1).h(-1) in oral exposure group and 24.1 ml.kg(-1).h(-1) in vein exposure group. TETS was eliminated from urine in rabbit. The eliminated amount of it from urine was more 5 times than from bile. All parameters of toxicokinetics of TETS were significantly different between the activated charcoal group and the control. Compared to the control, Tke1/2 of TETS in the activated charcoal group was equal to 55%, CL was increased over 3-fold, area under the curve was equal to 30%.

CONCLUSIONTETS was a poison eliminated very slowly in body. The eliminated amount of it from urine was more than from bile. The excretion of TETS could be quickened after activated charcoal by gavage.

Animals ; Antidotes ; administration & dosage ; Bile ; metabolism ; Bridged-Ring Compounds ; blood ; pharmacokinetics ; urine ; Charcoal ; administration & dosage ; Female ; Male ; Metabolic Clearance Rate ; drug effects ; Rabbits

PURPOSE: Postoperative ileus (POI) is an impairment of coordinated gastrointestinal (GI) motility that develops as a consequence of abdominal surgery and is a major factor contributing to patient morbidity and prolonged hospitalization. The aim of this study was to investigate the effects of different 5-hydroxytryptamine 4 (5-HT4) receptor agonists, which stimulate excitatory pathways, on a POI model. MATERIALS AND METHODS: The experimental model of POI in guinea pigs was created by laparotomy, gentle manipulation of the cecum for 60 seconds, and closure by suture, all under anesthesia. Different degrees of restoration of GI transit were measured by the migration of charcoal. Colonic transit was indirectly assessed via measurement of fecal pellet output every hour for 5 hours after administration of various doses of mosapride, tegaserod, prucalopride, and 5-HT. RESULTS: Charcoal transit assay showed that various 5-HT4 receptor agonists can accelerate delayed upper GI transit in a dose-dependent manner. However, fecal pellet output assay suggested that only prucalopride had a significant effect in accelerating colonic motility in POI. CONCLUSION: Although mosapride, tegaserod, and prucalopride produce beneficial effects to hasten upper GI transit in the POI model, prucalopride administered orally restores lower GI transit as well as upper GI transit after operation in a conscious guinea pig. This drug may serve as a useful candidate for examination in a clinical trial for POI.
Administration, Oral ; Animals ; Benzamides/pharmacology ; Benzofurans/administration & dosage/*pharmacology ; Charcoal/pharmacokinetics ; Colon/drug effects ; Dose-Response Relationship, Drug ; Gastrointestinal Motility/*drug effects ; Guinea Pigs ; Ileus/*surgery ; Indoles/pharmacology ; Laparotomy ; Male ; Morpholines/pharmacology ; Postoperative Complications/drug therapy ; Serotonin/pharmacology ; Serotonin 5-HT4 Receptor Agonists/*pharmacology