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van Luik EM, Vaes EWP, Vesseur MAM, Wilmes N, Meijs DAM, Laven SAJS, Mohseni-Alsalhi Z, de Haas S, Spaanderman MEA, Ghossein-Doha C. Sex Differences in the Anti-Hypertensive Effect of Calcium-Channel Blockers: A Systematic Review and Meta-Analysis. Biomedicines 2023; 11:1622. [PMID: 37371717 DOI: 10.3390/biomedicines11061622] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2023] [Revised: 05/23/2023] [Accepted: 05/30/2023] [Indexed: 06/29/2023] Open
Abstract
Cardiovascular disease (CVD) is the number one cause of death worldwide, with hypertension as the leading risk factor for both sexes. As sex may affect responsiveness to antihypertensive compounds, guidelines for CVD prevention might necessitate divergence between females and males. To this end, we studied the effectiveness of calcium channel blockers (CCB) on blood pressure (BP), heart rate (HR) and cardiac function between sexes. We performed a systematic review and meta-analysis on studies on CCB from inception to May 2020. Studies had to present both baseline and follow-up measurements of the outcome variables of interest and present data in a sex-stratified manner. Mean differences were calculated using a random-effects model. In total, 38 studies with 8202 participants were used for this review. In females as compared to males, systolic BP decreased by -27.6 mmHg (95%CI -36.4; -18.8) (-17.1% (95%CI -22.5;-11.6)) versus -14.4 mmHg (95%CI -19.0; -9.9) (-9.8% (95%CI -12.9;-6.7)) (between-sex difference p < 0.01), diastolic BP decreased by -14.1 (95%CI -18.8; -9.3) (-15.2%(95%CI -20.3;-10.1)) versus -10.6 mmHg (95%CI -14.0; -7.3) (-11.2% (95%CI -14.8;-7.7)) (between-sex difference p = 0.24). HR decreased by -1.8 bpm (95%CI -2.5; -1.2) (-2.5% (95%CI -3.4; -1.6)) in females compared to no change in males (0.3 bpm (95% CI -1.2; 1.8)) (between-sex difference p = 0.01). In conclusion, CCB lowers BP in both sexes, but the observed effect is larger in females as compared to males.
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Affiliation(s)
- Eveline M van Luik
- Department of Obstetrics and Gynaecology, Maastricht University Medical Center (MUMC+), 6229 HX Maastricht, The Netherlands
| | - Esmée W P Vaes
- Department of Obstetrics and Gynaecology, Maastricht University Medical Center (MUMC+), 6229 HX Maastricht, The Netherlands
| | - Maud A M Vesseur
- Department of Obstetrics and Gynaecology, Maastricht University Medical Center (MUMC+), 6229 HX Maastricht, The Netherlands
| | - Nick Wilmes
- Department of Obstetrics and Gynaecology, Maastricht University Medical Center (MUMC+), 6229 HX Maastricht, The Netherlands
- Cardiovascular Research Institute Maastricht, School for Cardiovascular Diseases, Maastricht University, 6229 ER Maastricht, The Netherlands
| | - Daniek A M Meijs
- Department of Obstetrics and Gynaecology, Maastricht University Medical Center (MUMC+), 6229 HX Maastricht, The Netherlands
- Cardiovascular Research Institute Maastricht, School for Cardiovascular Diseases, Maastricht University, 6229 ER Maastricht, The Netherlands
| | - Sophie A J S Laven
- Department of Obstetrics and Gynaecology, Maastricht University Medical Center (MUMC+), 6229 HX Maastricht, The Netherlands
| | - Zenab Mohseni-Alsalhi
- Department of Obstetrics and Gynaecology, Maastricht University Medical Center (MUMC+), 6229 HX Maastricht, The Netherlands
| | - Sander de Haas
- Department of Obstetrics and Gynaecology, Maastricht University Medical Center (MUMC+), 6229 HX Maastricht, The Netherlands
| | - Marc E A Spaanderman
- Department of Obstetrics and Gynaecology, Maastricht University Medical Center (MUMC+), 6229 HX Maastricht, The Netherlands
- Department of Obstetrics and Gynaecology, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands
| | - Chahinda Ghossein-Doha
- Department of Obstetrics and Gynaecology, Maastricht University Medical Center (MUMC+), 6229 HX Maastricht, The Netherlands
- Cardiovascular Research Institute Maastricht, School for Cardiovascular Diseases, Maastricht University, 6229 ER Maastricht, The Netherlands
- Department of Cardiology, Maastricht University Medical Center (MUMC+), 6229 HX Maastricht, The Netherlands
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Walrand S, Hesse M, d’Abadie P, Jamar F. Hepatic Arterial Buffer Response in Liver Radioembolization and Potential Use for Improved Cancer Therapy. Cancers (Basel) 2021; 13:cancers13071537. [PMID: 33810511 PMCID: PMC8036746 DOI: 10.3390/cancers13071537] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Revised: 03/22/2021] [Accepted: 03/23/2021] [Indexed: 02/08/2023] Open
Abstract
Simple Summary Radioembolization of hepatic tumors is performed by injecting 90Y or 166Ho loaded spheres into the hepatic artery. A twofold tumor to normal liver absorbed dose ratio is commonly obtained. In order to improve tumoral cell killing while preserving lobule function, co-injection of arterial vasoconstrictor has been proposed, but without success: the hepatic arterial buffer response quickly inhibits the arterioles vasoconstriction. The aim of the study is to investigate whether it is possible to take benefit from this buffer response, by co-infusing a mesenteric arterial vasodilator in order to dump the hepatic lobules arterial flow. Animal studies evidencing such mechanism are reviewed. Some potential mesenteric vasodilators are identified and their safety profile discussed. A four to sixfold improvement of the tumoral to normal tissue dose ratio is expected, pushing the therapy towards a real curative intention, especially in hepatocellular carcinoma (HCC), more frequent in obese subjects, and where ultra-selective spheres delivery is often not possible. Abstract Liver radioembolization is a treatment option for unresectable liver cancers, performed by infusion of 90Y or 166Ho loaded spheres in the hepatic artery. As tumoral cells are mainly perfused via the liver artery unlike hepatic lobules, a twofold tumor to normal liver dose ratio is commonly obtained. To improve tumoral cell killing while preserving lobules, co-infusion of arterial vasoconstrictor has been proposed but with limited success: the hepatic arterial buffer response (HABR) and hepatic vascular escape mechanism hamper the arterioles vasoconstriction. The proposed project aims to take benefit from the HABR by co-infusing a mesenteric arterial vasodilator: the portal flow enhancement inducing the vasoconstriction of the intra sinusoids arterioles barely impacts liver tumors that are mainly fed by novel and anarchic external arterioles. Animal studies were reviewed and dopexamine was identified as a promising safe candidate, reducing by four the hepatic lobules arterial flow. A clinical trial design is proposed. A four to sixfold improvement of the tumoral to normal tissue dose ratio is expected, pushing the therapy towards a real curative intention, especially in HCC where ultra-selective spheres delivery is often not possible.
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Margiotta-Casaluci L, Owen SF, Rand-Weaver M, Winter MJ. Testing the Translational Power of the Zebrafish: An Interspecies Analysis of Responses to Cardiovascular Drugs. Front Pharmacol 2019; 10:893. [PMID: 31474857 PMCID: PMC6707810 DOI: 10.3389/fphar.2019.00893] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2019] [Accepted: 07/16/2019] [Indexed: 12/04/2022] Open
Abstract
The zebrafish is rapidly emerging as a promising alternative in vivo model for the detection of drug-induced cardiovascular effects. Despite its increasing popularity, the ability of this model to inform the drug development process is often limited by the uncertainties around the quantitative relevance of zebrafish responses compared with nonclinical mammalian species and ultimately humans. In this test of concept study, we provide a comparative quantitative analysis of the in vivo cardiovascular responses of zebrafish, rat, dog, and human to three model compounds (propranolol, losartan, and captopril), which act as modulators of two key systems (beta-adrenergic and renin–angiotensin systems) involved in the regulation of cardiovascular functions. We used in vivo imaging techniques to generate novel experimental data of drug-mediated cardiovascular effects in zebrafish larvae. These data were combined with a database of interspecies mammalian responses (i.e., heart rate, blood flow, vessel diameter, and stroke volume) extracted from the literature to perform a meta-analysis of effect size and direction across multiple species. In spite of the high heterogeneity of study design parameters, our analysis highlighted that zebrafish and human responses were largely comparable in >80% of drug/endpoint combinations. However, it also revealed a high intraspecies variability, which, in some cases, prevented a conclusive interpretation of the drug-induced effect. Despite the shortcomings of our study, the meta-analysis approach, combined with a suitable data visualization strategy, enabled us to observe patterns of response that would likely remain undetected with more traditional methods of qualitative comparative analysis. We propose that expanding this approach to larger datasets encompassing multiple drugs and modes of action would enable a rigorous and systematic assessment of the applicability domain of the zebrafish from both a mechanistic and phenotypic standpoint. This will increase the confidence in its application for the early detection of adverse drug reactions in any major organ system.
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Affiliation(s)
| | - Stewart F Owen
- Global Safety, Health & Environment, AstraZeneca, Alderley Park, Macclesfield, United Kingdom
| | - Mariann Rand-Weaver
- College of Health and Life Sciences, Brunel University London, London, United Kingdom
| | - Matthew J Winter
- School of Biosciences, College of Life and Environmental Science, University of Exeter, Exeter, United Kingdom
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Huber R, Weisser S, Luedtke R. Effects of abdominal hot compresses on indocyanine green elimination--a randomized cross over study in healthy subjects. BMC Gastroenterol 2007; 7:27. [PMID: 17623067 PMCID: PMC1931598 DOI: 10.1186/1471-230x-7-27] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/16/2006] [Accepted: 07/10/2007] [Indexed: 01/10/2023] Open
Abstract
BACKGROUND Hot compresses on the right upper abdomen are used as support for patients with liver diseases in Germany. The study was designed to determine, whether they affect hepatic blood flow. METHODS Single dose kinetics of indocyanine green (ICG) were studied in 13 healthy subjects with or without hot compresses on the right upper abdomen over 40 minutes. The time interval between the investigations was 8 days, the sequence was randomly assigned. RESULTS Within non-linear kinetic analyses the area under the curves (AUC) were 23% (95% confidence interval [CI]: 5-37%) lower with hot compresses. In the initial phase, however, no differences were detected (p = 0.295). The differences occurred only in the late phase after 30-40 minutes, when the genuine ICG is eliminated from the plasma and only the degradation product remains. CONCLUSION Hot compresses have no effect on ICG elimination in healthy subjects but seem to affect the elimination of ICG metabolites. TRIAL REGISTRATION ClinicalTrials.gov NCT00484913.
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Affiliation(s)
- Roman Huber
- Department of Internal Medicine II, Freiburg University Hospital, Germany
| | - Sven Weisser
- Department of Internal Medicine II, Freiburg University Hospital, Germany
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De Visscher G, Leunens V, Borgers M, Reneman RS, Flameng W, van Rossem K. Nirs mediated CBF assessment: validating the indocyanine green bolus transit detection by comparison with coloured microsphere flowmetry. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2004; 540:37-45. [PMID: 15174600 DOI: 10.1007/978-1-4757-6125-2_7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/29/2023]
Affiliation(s)
- Geofrey De Visscher
- Department of Molecular Cell Biology, CARIM, University of Maastricht, The Netherlands
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Shih TTF, Chang CJ, Tseng WYI, Hsiao JK, Shen LC, Liu TW, Yang PC. Effect of calcium channel blockers on vertebral bone marrow perfusion of the lumbar spine. Radiology 2004; 231:24-30. [PMID: 15068937 DOI: 10.1148/radiol.2311030382] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
PURPOSE To investigate the effect of calcium channel blockers on blood perfusion of vertebral bone marrow in the lumbar spine. MATERIALS AND METHODS Sixteen healthy volunteers (eight men and eight women) underwent dynamic contrast material-enhanced magnetic resonance (MR) imaging of the lumbar spine. One hundred twenty minutes after the first MR examination, each subject ingested 10 mg sublingual nifedipine before undergoing a second MR examination 20-25 minutes later. Semiquantitative (peak enhancement ratio and enhancement slope) and quantitative (amplitude and rate constant of the exchange [K(out)]) parameters were analyzed with the time-intensity curve. Data obtained before and after administration of nifedipine were compared. The Wilcoxon signed rank test and Spearman rank correlation test were used. RESULTS Median peak enhancement ratio of vertebral bodies decreased from 0.60 (mean +/- SD, 0.68 +/- 0.29) to 0.51 (mean, 0.56 +/- 0.24) after administration of nifedipine. Median and mean decreases were 0.11 and 0.12 +/- 0.15, respectively, and the percentage difference was 17% (P =.005). A P value of less than.05 was considered to indicate a statistically significant difference. Median enhancement slope changed from 0.45 (mean, 0.45 +/- 0.13) to 0.41 (mean, 0.40 +/- 0.24). Median and mean changes were 0.05 and 0.04 +/- 0.23, respectively, and the percentage difference was 9% (P =.334). Median amplitude changed from 0.059 (mean, 0.059 +/- 0.028) to 0.045 (mean, 0.048 +/- 0.023). Median and mean changes were 0.008 and 0.011 +/- 0.025, respectively, and the percentage difference was 18% (P =.072). Median K(out) changed from 0.068 (mean, 0.063 +/- 0.018) to 0.067 (mean, 0.066 +/- 0.028). Median and mean changes were 0.011 and 0.004 +/- 0.028, respectively (P =.404). Nifedipine affected peak enhancement ratio significantly but did not affect enhancement slope, amplitude, or K(out). Data before and after administration of nifedipine showed no differences between men and women. Spearman rank correlation coefficients suggest no significance between the differences in heart rate and blood pressure and the differences in peak enhancement ratio, enhancement slope, amplitude, or K(out). CONCLUSION After sublingual administration of nifedipine, the peak enhancement ratio of vertebral bone marrow decreased.
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Affiliation(s)
- Tiffany Ting-Fang Shih
- Department of Radiology and Internal Medicine, National Taiwan University, Medical College and Hospital, 7 Chung-Shan S Rd, Taipei 100, Taiwan.
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Slehria S, Rajvanshi P, Ito Y, Sokhi RP, Bhargava KK, Palestro CJ, McCuskey RS, Gupta S. Hepatic sinusoidal vasodilators improve transplanted cell engraftment and ameliorate microcirculatory perturbations in the liver. Hepatology 2002; 35:1320-8. [PMID: 12029617 DOI: 10.1053/jhep.2002.33201] [Citation(s) in RCA: 80] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
After transplantation, hepatocytes entering liver sinusoids are engrafted, whereas cells entrapped in portal spaces are cleared. We studied whether hepatic sinusoidal dilatation will increase the entry of transplanted cells in the liver lobule, improve cell engraftment, and decrease microcirculatory perturbations. F344 rat hepatocytes were transplanted intrasplenically into syngeneic dipeptidyl peptidase IV (DPPIV)-deficient rats. Animals were treated with adrenergic receptor blockers (phentolamine, labetalol), a calcium channel blocker (nifedipine), and splanchnic vasodilators (nitroglycerine, calcitonin gene-related peptide [CGRP], glucagon). Transplanted cells were localized by histochemistry. The hepatic microcirculation was studied with in vivo videomicroscopy. Changes in cell translocations were analyzed by injection of (99m)Tc-labeled hepatocytes. Pretreatment with phentolamine and nitroglycerine increased transplanted cell entry in liver sinusoids, whereas labetalol, nifedipine, CGRP, and glucagon were ineffective. Increased deposition of transplanted cells in sinusoids resulted in greater cell engraftment. In vivo microscopy showed disruption of sinusoidal blood flow immediately after cell transplantation with circulatory restoration requiring more than 12 to 24 hours after cell transplantation. However, in nitroglycerine-treated animals, sinusoidal blood flow was perturbed less. Nitroglycerine did not meaningfully increase intrapulmonary cell translocations. In conclusion, these findings indicate that hepatic sinusoidal capacitance is regulated by alpha-adrenergic- and nitroglycerine-responsive elements. Sinusoidal vasodilatation benefited intrahepatic distribution of transplanted cells and restored hepatic microcirculation after cell transplantation. This shall facilitate optimization of clinical cell transplantation and offers novel ways to investigate vascular mechanisms regulating hepatic sinusoidal reactivity.
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Affiliation(s)
- Sanjeev Slehria
- Marion Bessin Liver Research Center, Department of Medicine, Albert Einstein College of Medicine, Bronx, NY 10461, USA
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De Visscher G, van Rossem K, Van Reempts J, Borgers M, Flameng W, Reneman RS. Cerebral blood flow assessment with indocyanine green bolus transit detection by near-infrared spectroscopy in the rat. Comp Biochem Physiol A Mol Integr Physiol 2002; 132:87-95. [PMID: 12062195 DOI: 10.1016/s1095-6433(01)00533-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
In this study we evaluated the feasibility of measuring cerebral blood flow in rats by monitoring the transit of an indocyanine green bolus through the brain with multiwavelength near-infrared spectroscopy. Different volumes of a 1 mg/ml indocyanine green solution (5, 15, 25, 50 microl) were injected intravenously in the search for an optimal dose. Clear transit curves were obtained with all doses and a blood flow index could easily be determined. The indocyanine green signal obtained with the bolus of 5 microl rapidly returned to baseline and interfered minimally with the haemoglobin and cytochrome oxidase signals. This dose was used in a second study to evaluate the reproducibility of the signal and the effect of hypercapnia. Two groups of rats received 7 repetitive boli of indocyanine green. In one group, 7% CO(2) was added to the gas mixture before the second, fourth and sixth indocyanine green injection. Hypercapnia consistently caused a significant increase in blood flow index, cerebral haemoglobin concentration and O(2)-saturation. In the control group these variables remained stable in time. We conclude that monitoring of the transit of an indocyanine green bolus with multiwavelength near-infrared spectroscopy can be used to assess cerebral blood flow qualitatively in rats in combination with continuous monitoring of brain oxygenation.
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Affiliation(s)
- Geofrey De Visscher
- Department of Physiology, CARIM, University of Maastricht, Maastricht, The Netherlands.
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Abstract
Although the study of hepatic circulation is complicated by the dual blood supply and complex anatomy of the liver, many distinct methods are available to facilitate its study. Before embarking on an investigation of hepatic hemodynamics, the investigator must be familiar with the available methods and their applications. All methods have their own attributes and limitations. No one method is superior to the others, but, depending on the aspect of hepatic hemodynamics to be investigated, a particular methodology may yield distinct advantages.
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Affiliation(s)
- N Garcia
- Department of Internal Medicine, Division of Gastroenterology, Hepatology and Nutrition, Medical College of Virginia, Virginia Commonwealth University, USA.
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Burggraaf J, Schoemaker RC, Lentjes EG, Cohen AF. Sorbitol as a marker for drug-induced decreases of variable duration in liver blood flow in healthy volunteers. Eur J Pharm Sci 2000; 12:133-9. [PMID: 11102741 DOI: 10.1016/s0928-0987(00)00148-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
OBJECTIVE Sorbitol has been suggested as a suitable marker to assess liver blood flow (LBF), after it was shown to adequately reflect prolonged changes in LBF but changes of a shorter duration have not been investigated. We therefore used sorbitol to evaluate drug-induced decreases in LBF of variable duration with i.v. infusions of somatostatin and its synthetic analogue octreotide. METHODS In a double-blind, placebo controlled, randomised study, six healthy males received sorbitol for 170 min. At sorbitol steady state, which was at 45 min after the start of the infusion (t=0), somatostatin or octreotide was infused for 30 min. Sampling for sorbitol assay and echo-Doppler hepatic portal vein flow measurements were done regularly and treatments were compared using ANOVA. RESULTS The sorbitol AUC over the 30-min intervention period was 15% (95% C.I.: +4, +22%) and 13% (+5, +24%) higher compared to placebo after somatostatin and octreotide respectively. The decline of sorbitol levels after termination of the intervention was faster for somatostatin compared to octreotide, demonstrated by the difference in the AUC (0-2 h) with placebo which was 8% (-3, +19%) lower after somatostatin, and 15% (+5, +26%) after octreotide. Portal venous blood flow decreased during the 30-min interventions; after somatostatin 27% (-14, -40%) and after octreotide 29% (-17, -42%). Portal flow was lower than placebo during the entire experiment after octreotide 30% (-10, -50%), but not after somatostatin 13% (-33, +7%). Changes in sorbitol levels and portal venous blood flow occurred simultaneously and were well correlated for each individual, making it likely that the interventions did not interfere with metabolism. CONCLUSION Sorbitol can be used to adequately assess decreases in LBF of variable duration in healthy volunteers.
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Affiliation(s)
- J Burggraaf
- Centre for Human Drug Research and Department of Clinical Chemistry, Leiden University Medical Centre, Leiden, The Netherlands.
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Roberts MS, Anissimov YG. Modeling of hepatic elimination and organ distribution kinetics with the extended convection-dispersion model. JOURNAL OF PHARMACOKINETICS AND BIOPHARMACEUTICS 1999; 27:343-82. [PMID: 10826128 DOI: 10.1023/a:1020992421184] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
The conventional convection-dispersion (also called axial dispersion) model is widely used to interrelate hepatic availability (F) and clearance (Cl) with the morphology and physiology of the liver and to predict effects such as changes in liver blood flow on F and Cl. An extended form of the convection-dispersion model has been developed to adequately describe the outflow concentration-time profiles for vascular markers at both short and long times after bolus injections into perfused livers. The model, based on flux concentration and a convolution of catheters and large vessels, assumes that solute elimination in hepatocytes follows either fast distribution into or radial diffusion in hepatocytes. The model includes a secondary vascular compartment, postulated to be interconnecting sinusoids. Analysis of the mean hepatic transit time (MTT) and normalized variance (CV2) of solutes with extraction showed that the discrepancy between the predictions of MTT and CV2 for the extended and unweighted conventional convection-dispersion models decreases as hepatic extraction increases. A correspondence of more than 95% in F and Cl exists for all solute extractions. In addition, the analysis showed that the outflow concentration-time profiles for both the extended and conventional models are essentially identical irrespective of the magnitude of rate constants representing permeability, volume, and clearance parameters, providing that there is significant hepatic extraction. In conclusion, the application of a newly developed extended convection-dispersion model has shown that the unweighted conventional convection-dispersion model can be used to describe the disposition of extracted solutes and, in particular, to estimate hepatic availability and clearance in both experimental and clinical situations.
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Affiliation(s)
- M S Roberts
- Department of Medicine, University of Queensland, Princess Alexandra Hospital, Woolloongabba, Australia.
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