Chronobiological Evaluation of the Active Biliary and Renal Secretion of Ampicillin

White, Catherine A.; Pardue, Roseline L.; Huang, Chunhua; Warren, J. B.

doi:10.3109/07420529509057290

Cited by 18 publications

(25 citation statements)

References 13 publications

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“…Studies done in our laboratory have found that LEA has a lower systemic clearance, greater uptake, and retention by the organs of the reticuloendothelial system (RES) and prolonged circulating blood levels as compared to free ampicillin. 8 These results correlate well with other studies found in the literature. [12][13][14] These characteristics of liposomal formulations may reduce the effect of diurnal biological rhythms on the apparent clearance of encapsulated drug.…”

Section: Introductionsupporting

confidence: 94%

“…Similar temporal changes in pharmacokinetics and nephrotoxicity of tobramycin in rats were also documented by Lin et al 6,7 The renal and biliary clearance (active secretion) of ampicillin in rats also exhibits a circadian rhythm which results in the plasma concentration-time profiles having a 2-fold longer MRT during the resting phase (1200) as compared to the active phase (2400). 8 The observed chronobiological variations may be due to the changes in the rates of biliary and renal excretion. Renal clearance is generally lower during the rest cycle and reaches a maximum in the middle of the active cycle.…”

Section: Introductionmentioning

confidence: 99%

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Chronokinetics of Liposomal Encapsulated Ampicillin in Fasting and Nonfasting Rats

Pardue

White

1996

Journal of Pharmaceutical Sciences

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The chronobiological effect on the pharmacokinetics of liposomal encapsulated ampicillin (LEA) was compared at noon (1200) and midnight (2400) after intravenous injection of 50 mg/kg of LEA in rats. The effects of fasting on the circadian rhythms of LEA were also investigated. Serial blood samples were collected for 2 h. Bile and urine were collected during the entire study. Plasma data was analyzed by noncompartmental methods. Dosing of LEA at 2400, when the animals were active, resulted in a 50% decrease in mean residence time (MRT) and a 20% increase in systemic clearance (Cltotal). The increase in Cltotal was reflected by increases in biliary (Clbile) and renal (Clrenal) clearance at 2400. In addition, the steady-state volume of distribution (Vss) at 2400 was also decreased by about 50% as compared to dosing at 1200. Interestingly, no difference in the pharmacokinetic parameters were observed in fasting animals at 1200 and 2400. Since rats consume very little food during their sleep cycle, restriction of food intake did not have any affect on the pharmacokinetics of LEA at 1200. However, fasting rats had an approximately 36% decrease in Cltotal as compared to nonfasting rats at 2400. This decrease in systemic clearance was paralleled by a 60% and 24% decrease in Clbile and Clrenal, respectively. These variations could be attributed to changes in bile composition and/or lipoprotein concentrations in the plasma as a result of "forced" fasting at 2400 when the animals are generally more active and food intake is high.

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Section: Introductionsupporting

confidence: 94%

Section: Introductionmentioning

confidence: 99%

Chronokinetics of Liposomal Encapsulated Ampicillin in Fasting and Nonfasting Rats

Pardue

White

1996

Journal of Pharmaceutical Sciences

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“…Several studies have reported temporal variations in the pharmacokinetics of antimicrobial drugs (1,3,13,16,26,(29)(30)(31). Our results show that the total clearance of ceftriaxone varies rhythmically during the day, with its maximum during the dark (activity) period and its minimum during the light (rest) period in rats; however, it must be noted that as intravenous administration was not performed, bioavailability was not included in our CL T calculation.…”

mentioning

confidence: 51%

“…A population pharmacokinetic study of amikacin in humans showed higher values for k el in the morning than in the evening. Ampicillin biliar and renal clearances were significantly higher during the active cycle of rats than during the sleep cycle (16,30).…”

mentioning

confidence: 92%

“…Basal bile flow has been reported to exhibit a circadian rhythm with higher values during the active phase of rats (10). The biliar anion carrier system shows its maximum transport capacity during activity (rather than rest) in rats (16,30). Urinary water, protein and glycosaminoglycan excretions, and glomerular filtration rate (GFR) and renal plasma flow (RPF) show a circadian rhythmicity in rats, with markedly increased values observed during the dark phase in the animals (6,21,22).…”

mentioning

confidence: 99%

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Daily Variations in Ceftriaxone Pharmacokinetics in Rats

Rebuelto

Ambros

Rubio

2003

Antimicrob Agents Chemother

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The aim of this study was to determine whether the time of day ceftriaxone was administered modified its pharmacokinetics. Ceftriaxone was given intraperitoneally at either 0400, 1000, 1600, and 2200 h to Sprague-Dawley rats synchronized under a light-dark cycle of 12 h of light and 12 h of dark. Pharmacokinetic parameters were analyzed for the presence of a 24-h rhythm. Results showed significant daily variations (P < 0.05) in ceftriaxone clearance, with the highest values during the dark phase. It is concluded that time-dependent variations in ceftriaxone pharmacokinetics may affect the therapeutic efficacy of current once-daily dosing schedules

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Rat auxiliary liver transplantation without portal vein reconstruction: Comparison with the portal vein‐arterialized model

et al. 2001

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Auxiliary liver transplantation (ALT) has been reintroduced in clinical cases recently and is now believed to be a viable alternative to orthotopic liver transplantation. To provide a simple rat ALT model for studying the physiological and immunological aspects of the ALT graft, a new ALT was performed, and the comparison between this new model and the portal arterialized one that was reported by other investigators was carried out. At first, we confirmed that liver could tolerate the deprivation of its portal flow well, using a portosystemic shunted rat model. The new rat ALT model, in which the ALT graft obtained its blood inflow only from the hepatic artery, was then performed. Our results demonstrated that 50% of the hepatic artery-alone ALT graft showed almost normal structure histologically at 1 month after grafting, with bile secretion preserved. By contrast, only 8% 1-month graft survival was noted in the portal arterialized group, and all grafts stopped bile secretion 1 week after operation. In conclusion, with arterial blood supply alone, the ALT graft survived and demonstrated normal bile secretion function for more than 1 month. Portal vein arterialization is not an appropriate way to establish the graft's blood supply if no pressure adjustment measures were taken in advance.

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Chronobiological Evaluation of the Active Biliary and Renal Secretion of Ampicillin

Cited by 18 publications

References 13 publications

Chronokinetics of Liposomal Encapsulated Ampicillin in Fasting and Nonfasting Rats

Chronokinetics of Liposomal Encapsulated Ampicillin in Fasting and Nonfasting Rats

Daily Variations in Ceftriaxone Pharmacokinetics in Rats

Rat auxiliary liver transplantation without portal vein reconstruction: Comparison with the portal vein‐arterialized model

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