Allometric Analysis of Oxolinic Acid, Flumequine and Enrofloxacin in Fish

World Applied Sciences Journal 24 (2): 234-239, 2013 ISSN 1818-4952 IDOSI Publications, 2013 DOI: 10.5829/idosi.wasj.2013.24.02.836 Allometric Analysis of Oxolinic Acid, Flumequine and Enrofloxacin in Fish Anelyia M. Haritova and Lubomir D. Lashev Department of Pharmacology, Physiology and Physiological Chemistry, Faculty of Veterinary Medicine, Trakia Universiry, 6000 Stara Zagora, Bulgaria Submitted: Nov 23, 2012; Accepted: Jan 5, 2013; Published: Aug 5, 2013 Abstract: Allometric analysis of the total body clearance (Cl B), steady-state volume of distribution (V ss) and elimination half-life (t 1/2 ) based on the literature data in fish species was performed for oxolinic acid, flumequine, enrofloxacin. Values of Cl B and V ss show allometric dependence on body weight but values of t 1/2 can not be predicted after scaling toward body weight. Significant differences were found between allometric equations characteristic for the fish species and the homeotherm species. These results are reflectors of the differences in the level of the metabolic rate between cold-blooded and warm-blooded animal species. Key words: Quinolones Pharmacokinetics Allometric scaling Fish INTRODUCTION temperature and its salinity [14-17]. Another opinion also exists - neither water salinity nor fish species seemed to The allometric scaling is used as a method for play an important role in the disposition of oxytetracycline determining the pharmacokinetic characteristics and dose in salmonids rainbow trout and Chinook salmon [18]. of a drug in cases of lack of scientific data or empirical Some of the papers show that allometric relationship is experience for an animal species [1]. The basis of the more complicated, but it is possible to be recognized method is the relationship between metabolic rate and [19,20]. The reason why allometric scaling is applied with body weight of animal species. The aim is determining the deliberation is because it can lead to estimation of wrong dependencies of the dose defining pharmacokinetic dosage regimens by ignoring factors which influence the parameters of drugs (elimination half life, total body allometric relationship. Published investigations concern clearance, volume of distribution) on body weight [1-3]. antibacterial drugs are based on data for mammals and Allometric scaling relationships are based on the principle birds [3,21-24]. The only data of in poikiloterms is on that the amount of drug administered to an animal is enrofloxacin and iguanas [12]. Data about antibacterials in related to its body mass [4]. Most formularies are based fish are lacking. Current investigation aimed to analyze the on data for mammals. The present pharmacological published information about pharmacokinetic parameters information for birds is delivered from studies on (t 1/2, Cl B and V ss) of enrofloxacin, flumequine and oxolinic relatively small number of species mostly form family acid in order to find allometric relationship on the body Galliformes, other poultry species, pigeons and quails [1]. weight in fish species. Currently, these antibacterial Extrapolation of dosing regimens by using allometric substances are used in the fish farms and the information scaling from mammals and domestic poultry to other about them is relatively sufficient for such type of species is complicated, limited and differences were found investigations. even within the class of birds [1,5,6,]. The pharmacokinetic data for poikiloterm vertebrates MATERIALS AND METHODS are quite scarce and are available mainly for fish species [7] and reptiles [8-13]. The pharmacokinetics of drugs in The allometric analysis of pharmacokinetic poikilotherm species (especially fish) is influenced of more parameters of enrofloxacin, flumequine and oxolinic acid factors compared to birds and mammals and the most was performed using data from published studies for fish popular of them are the environmental water species, cited in Table 1. Only data for intravenously Corresponding Author: Lubomir D. Lashev, Department of Pharmacology, Physiology and Physiological Chemistry, Faculty of Veterinary Medicine, Trakia Universiry, 6000 Stara Zagora, Bulgaria. Tel.: +359 42 699622. 234

Table 1: Selected pharmacokinetic data for flumequine, enrofloxacin and oxolinic acid in fish species, included in the analysis. Species BW (kg) T C t 1/2 (h) Cl B (l/kg/h) V ss (l/kg) References Flumequine Eel (Anguila anguila) 0.10 23 232 0.006 1.2 [25] 0.19 23 283 0.012 3.4 [26] Halibut (Hippoglossus hippoglossus) 0.07 9.5 62 0.058 3.8 [25] 2.00 9 43 0.05 2.3 [27] 0.09 10 32 0.12 2.99 [28] Atlantic salmon (Salmo salar L.) 0.24 10.2 22.8 0.18 3.5 [29] 0.35 7 36.4 0.07 3.41 [30] Gilthead sea bream (Sparus aurata) 0.17 19 30 0.05 0.57 [31] Sea bass (Dicentrarchus labrax L.) 0.12 18 10.71 0.156 1.51 [32] Corkwing wrasse (Symphodus melops) 0.073 12 26 - - [33] Channel catfish (Ictalurus punctatus) 0.66 24 25 0.015 0.53 [34] Turbot (Scophthalmus maximus) 0.21 18 34 0.17 3.75 [28] Cod (Gadus morhua) 0.17 8 75 0.024 2.4 [35] Goldsinny wrasse (Ctenolabrus rupestris) 0.038 14 31 0.14 2.15 [35] Pike eel (Muraenesox cinereus) 0.28 22.5 9.38 0.07 - [36] Turbot (Scophthalmus maximus) 0.078 16 38 0.043 0.8 [25] Enrofloxacin Rainbow Trout (Oncorhynchos mykiss) 0.10 15 24.4 0.0916 2.77 [37] 0.10 15 30.4 0.0584 2.34 [37] Brown trout (Salmo trutta fario) 0.17 10 19.1 0.14 3.4 [38] Korean catfish (Silurus asotus) 0.32 25 17.44 0.17 3.93 [39] Red pacu (Collossoma brachypomum) 0.042 25 28.9 - - [40] Atlantic salmon (Salmo salar L.) 0.24 10.2 34.2 0.14 6.1 [29] Koi carp (Cyprinus carpio) 0.078 27.5 17.9 0.121 3.1 [41] Nile tilapia (Oreochromis niloticus) 0.65 25 55.2 0.148 1.11 [42] Oxolinic acid Atlantic salmon (Salmo salar L.) 0.24 10.2 18.2 0.28 5.4 [29] Sea bass (Dicentrarchus labrax L.) 0.11 14 315 0.033 14.7 [43] 0.11 22 55.4 0.06 5.2 [43] 0.10 15.4 87-2.6 [44] Gilthead sea bream (Sparus aurata L.) 0.10 20 12.6 0.15 2.11 [31] Sharpsnout sea bream (Diplodus puntazzo) 0.09 19 10 0.2 2.1 [31] Red seabream (Pagrus major) 0.49 15.4 20 0.1 2.9 [45] Rainbow Trout (Oncorhynchos mykiss) 0.40 15 123 0.02 3.4 [45] 0.49 15 19 0.1 2.9 [45] 0.54 16 69.7 0.02 1.9 [46] 0.80 14 69.3 0.017 1.82 [47] 0.126 15 69.3 0.021 1.88 [48] Halibut (Hippoglossus hippoglossus) 2.250 9 52 0.044 3 [33] Pike eel (Muraenesox cinereus) 0.28 22 14.84 0.07 - [36] Cod (Gadus morhua) 0.125 8 84 0.05 5.5 [49] BW- body weight, C - water temperature, t - elimination half-life, Cl - body clearance, V - volume of distribution 1/2 B ss administered drugs were used. The matrices of interest environmental water temperature did not improve the were serum or plasma. For each drug analysis, data for output of allometric analysis. Therefore, in the calculation total body clearance (Cl B), volume of distribution at procedures the influence of temperature on the values of steady-state (V ss) and elimination half-life (t 1/2â) were the pharmacokinetic parameters was neglected. The linear included. Data for body weights were collected from the regression of log t 1/2 (h), log V ss (l) or log Cl B (l/kg) vs. log same studies. Separation based on the age has not been body weight W (kg) was analyzed so that estimates of the done. All values were calculated on the basis of any intercept c and slope b could be computed by the single published value of pharmacokinetic parameters following equation: versus fish body weight from each study. The experimental data refer to animals reared in water with log(pharmacokinetic parameter of intercept)= logc + different temperature. Their separation according to the b(logw). 235

Table 2: Values of the allometric relationship for five antibacterials in fish species. Pharmacokinetic parameter Allometric parameter Flumequine Enrofloxacin Oxolinic acid t 1/2 (h) a 36.20 37.19 34.03 b 0.08871 0.18 0.32 R 0.2173 0.4008 0.4421 P 0.2 0.2 0.2 n 11 8 10 Cl B (l/kg/h) a 0.039 0.200 0.0431 b 0.7213 1.311 0.5551 R 0.6254 0.9649 0.7820 P < 0.05 < 0.001 < 0.001 n 13 7 11 V ss (l/kg) a 1.804 2.01 3.175 b 0.9623 0.780 1.0147 R 0.8110 0.7664 0.9332 P < 0.001 < 0.05 < 0.001 n 14 7 11 a - allometric coefficient, b - allometric exponent; R - correlation coefficient; P - level of statistical significance; n - number of included data The allometric equation was then applied based on the Oxolinic acid: b following power function: Y = aw, t = 34.03W ; Cl = 0.043W ; V = 3.18W Where Y is the value of the respective DISCUSSION pharmacokinetic parameter (t 1/2ß, Vssor Cl B),? (antilogathm of logc) is the coefficient, W is the body weight and b is Grouping of animal species in clusters according to the exponent of allometric equation. The least squares their belonging to different orders improve allometric linear regression method was used for estimation of scaling as it has been demonstrated in previous correlation between pharmacokinetic parameters of investigations [2,24,50]. The findings of Hunter et al. [1] interest and body weight. Statistical analysis was suggest that better prediction of the pharmacokinetic done by Statistica 6.1 software (Statistica for Windows, parameters and dosage regimen for birds are generated Stat Soft. Inc. Tulsa, OK, USA). Double logarithmic when using only avian data and that improvements in plots of body mass vs. t 1/2ß,Vssor ClB were constructed prediction are seen in drugs that are renally excreted. This to demonstrate significance found in the regression idea is also valid for fish species. When the data for fish analysis. are discussed, it should be acknowledged that there is no universal value of b and the results should be interpreted RESULTS more in the light of existence or absence of allometric dependence between pharmacokinetic parameters and Significant allometric relationship of total body body weight [20]. It is well known that some clearance and volume of distribution on body weight (V ss) pharmacokinetic parameters in fish species are was found for the three substances (Table 2). The data temperature dependent [7] but dividing the data about about the elimination half life (t 1/2) show absence of any fish in two sets according to the water temperature did not relationship between this parameter and body weight for improve the output of allometric analysis. Additionally, it the tested drugs. The equations based on the calculations has been reported that allometric exponent did not vary which could be used for estimation of the respective with changes of the temperature for ectoterms [19]. pharmacokinetic parameters are as follows: Therefore, all the available values of pharmacokinetic parameters were simultaneously included in calculations. Flumequine: Ideal situation is to scale values of Cl B for 0.089 0.72 0.96 t 1/2 = 36.20W ; Cl B = 0.039W ; V ss = 1.8W compounds that are excreted, without metabolism through Enrofloxacin: kidneys. In the current study we dealt with drugs that are 0.089 1.31 0.78 t 1/2 = 37.19W ; Cl B = 0.2W ; V ss = 2.1W metabolized in a low degree. Exponent of 0.75 was widely 236 0.32 0.56 1.01 1/2 B ss

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