Method for experimental finasteride simulation of induction of functional activity of glycoprotein-p. RU patent 2504018.
 Method for simulating enamel demineralisation centre / 2503067Dental bracket is fixed onto an extracted tooth. A centre surrounding the dental bracket on a vestibular surface is limited by a wax layer. The tooth is immersed into a separated container with a demineralising gel consisting of (wt %): calcium dihydrophosphate - 0.04-0.08, lactic acid - 0.8-1.0, praestol 2510 - 3.0-4.5, sodium hydroxide - 0.4, distilled water - the rest. Then, the container with the teeth is placed in a thermostat at pH=4.5 for 96 hours. |
 Method of simulating atherosclerosis / 2500041For the purpose of diagnosing, preventing and treating the same disease, a cholesterol powder in the amount of 1%, margarin 10%, mercazolilum 10 mg/kg and vitamin D 2.5 IU per kg of body weight is added to the laboratory rats' feed. That is combined with performing an operation of ligating a left renal pedicle with a non-absorbable suture and underrunning a right upper pole with 2/3 of the organ being preserved. |
| Method for combined tadalafil and l-norvaline correction of l-name induced nitrogen oxide deficiency in experiment / 2500040 Nitrogen oxide deficiency is simulated by the daily 7-day intraperitoneal introduction of N-nitro-L-arginine methyl ester 25 mg/kg into experimental Wistar male rats. The nitrogen oxide deficiency is corrected by the simultaneous 7-day intragastric introduction of a combination of tadalafil 0.09 mg/kg and L-norvaline 10 mg/kg once a day. |
| Method for simulating primary biliary cirrhosis / 2500039 Primary biliary cirrhosis is simulated by introducing 45-50% alcoholic solution of picryl sulfonic acid 0.08-0.12 ml into rat's bulbar duodenal lumen and terminal ileum every 5-10 minutes. The primary biliary cirrhosis is diagnosed 1-1.5 months later. |
| Method for simulating chronic infected bone wound / 2499295 Bone defect is formed along the bone; the museum strain Staphylococcus Aureus No.5 culture in the amount of 40-45 mln CFU per 1 kg of experimental animal's body weight mixed with 0.1 ml of sterile silica sand are placed therein. Three days later, necrotic mass and purulent matter are removed from the bone defect. The wound is re-infected with the same culture in a dose of 20-25 mln CFU per 1 kg of body weight. The wound is further preserved in the form of a fistula. |
| Method for simulating diabetic macular oedema / 2498415 Alloxan is introduced into rat's peritoneum in a dose of 15.0 mg/100 g of weight. Then, 6.5 weeks after alloxan has been introduced, and experimental diabetes has been developed, insulin-like growth factor 1 (IGF-1) 1 mcl is introduced into the vitreous body from an intravitreous approach. |
| Method for dermal flap survival growth in reduced circulation with sildenafil / 2498414 Dermal flap is simulated in laboratory animals on the second day of experiment. Sildenafil 2.2 mg/kg is introduced intraperitoneally on the first, third and fifth day of the experiment. |
| Method of diagnosing affection of peripheral nerves in laboratory animals in remote period of exposure to mercuric chloride / 2497448 Invention relates to field of medicine, in particular to experimental medicine. Stimulatory myography is performed to laboratory animals 9 weeks after exposure to toxicant is stopped. Amplitude of M-response (mV) and duration of M-response (ms) on median nerve are registered. Area of involvement of motor units is calculated. Calculation of canonic value is performed. Obtained results are compared with constant and if Cv is higher than 8.9, conclusion about absence of signs of chronic exposure to mercuric chloride is made, if Cv is lower or equals 8.9, affection of peripheral nerves in remote period of exposure to mercuric chloride is diagnosed. |
| Method of pharmacological correction of sceletal muscle ischemia with silnedafil including in l-name induced nitrogen oxide deficiency / 2497203 Calf muscle ischemia is simulated, including in a combination with additional simulation of nitrogen oxide deficiency by intraperitoneal introduction of the nitrogen oxide synthesis blocker N-nitro-L-arginine of methyl ester (L-NAME) 25 mg/kg daily for 7 days. In both cases, the ischemia is corrected by intragastric introduction of sildenafil 2.2 mg/kg on the first, third and fifth days of experiment. |
 Method for simulating prenatal hypoxic encephalopathy in small laboratory animals / 2497202Sodium nitrite 50 mg/kg is introduced subcutaneously into small laboratory female animals daily from 10th to 19th day of pregnancy. |
 Method for modeling acute pancreatitis / 2244345As experimental animals one should apply mongrel dogs of 12-17 kg body weight. Under general anesthesia one should conduct superior-median laparotomy, introduce 3.0 ml 70%-ethanol solution under pancreatic capsule and then laparotomic wound should be sutured up. Manipulation should be performed once. The method provides modeling adequate acute pancreatic inflammation at no side effects being very simple in implementation. |
 Method and device for studying transosseous osteosynthesis model stiffness / 2246139Method involves studying transverse longitudinal and rotation stiffness characteristics. The studies are carried out step-by-step from the first order units to complete external fixation apparatus structure. The device has frame and is provided with calibration loads, wire rope, displacement indicators, strip for fastening to loading end of bone imitator fragment, beam for fixing displacement indicators, beams having unit for modeling longitudinal and transverse loadings. The frame is manufactured as parallelepiped. The fixing panel has openings for bone imitator, for fixing external fixation apparatus and yoke connection union and is fixed in end face part of the frame. Beam for fixing displacement indicators has longitudinal slit for fixing the indicators and arranging them on lateral slots in frame base. The beams having unit for modeling rotational, longitudinal and transverse loadings are arranged on lateral frame sides on lateral slots in base. |
 Method for experimental modeling urinary calculosis / 2248045The present innovation deals with modeling urinary calculosis in rats due to injecting intraperitoneally 60%-glucose solution at 1 ml/100 g animal body weight twice daily for 2 mo. The method is very simple and enables to achieve lithogenesis in 25% experimental animals. |
| Method for applying wave action to pathogenic microorganisms, viruses and tumor cells in experiment / 2250788 Method involves using Hann diode crystal with proper frequencies of pathogenic microorganisms and cells during their death period or during the stimulating factors action period being applied. |
 Method for modeling hypoxia with hypercapnia in animals / 2251158Hypoxia with hypercapnia should be modeled due to creating a closed system of inhaled air circulation. Air enters lungs out of hermetically sealed reservoir and at expiration returns back. The process of recirculation is supplied with an apparatus of artificial pulmonary ventilation. The innovation suggested provides steadiness in development of hypoxia with hypercapnia excluding the development of stressor reaction. Conditions should be created to carry out any manipulations with an animal in the course of an experiment. |
| Method for obtaining parodontitis model / 2252009 The present innovation should be carried out for the purpose to study ethiology and pathogenesis of parodontitis. One should affect with emotional stress in experimental animals (mature rats) due to placing 10-11 experimental animals into the cage at area of 0.018 sq. cm/animal. Before placing into the cage one should create artificial dental plaque around the cervix of the upper and lower incisors with the help of stomatological cement for every experimental animal. In the course of modeling all experimental animals should eat paste-like food. The method enables to shorten terms for obtaining the model desired and increase its similarity with pathomorphological manifestations of human parodontitis. |
 Acupuncture point electric model device / 2252743Device has input first variable resistor, capacitor and permanent resistor. Permanent resistor is connected to arm second and third variable resistors. Second ends of variable resistors are connected with motionless contacts of polarized relay. Movable contact of relay is connected to common bus. Input of device is connected to amplifier which has output connected with control wiring of polarized relay. Second end of wiring is connected with common bus. Device is intended for electrical modeling of balanced and misbalanced conditions of acupuncture point at electropunctural action with unlike-poled signals due to liquidation mutual errors at any circuit of opposite arms of the device. Values of active resistances can be installed independently at any arm of device. |
| Method for modeling hypoxic encephalopathy / 2253152 Laboratory animals should be once injected intraperitoneally or intravenously with phenylhydrazine at the dosage of 100-150 mg/kg. |
| Method for modeling chronic toxic nephropathy / 2253153 At studying the mechanisms of heavy metals toxic action, in particular, cadmium upon renal function, it is suggested to introduce cadmium sulfate solution into stomach once daily for 2 mo at the dosage of 0.5 mg/kg, on conversion to metal, where cadmium corresponds to 0.5 mg per 1 ml solution. The present innovation enables to study the pathology in dynamics of development and elaborate and searching preparations for treating and preventing chronic toxic nephropathy. |
| Method for stopping carcinoma cells division in a biological object / 2253903 Method involves exposing cell or cell group to external power source. At least two electrodes are introduced before treating the cells. One of electrodes is set on cytoplasmatic external cell membrane surface and the other one cell membrane and membrane potential value is measured. External electric voltage source is connected to the introduced electrodes oppositely in polarity with cell membrane potential difference value being not less than cell membrane potential. |
FIELD: medicine.
SUBSTANCE: invention aims at studying a membership of the analysed drug preparations among efflux carrier protein Pgp (glycoprotein P) substrates. That is ensured by the experimental simulation of the induction of functional activity of the same protein. Finasteride is used as an inducing preparation. The preparation is introduced into rabbits intragastrically in the form of a suspension in olive oil in a daily dose of 0.225 mg/kg of animal's body weight for 14 days.
EFFECT: creating the model; the safe method requires no expensive laboratory special equipment and materials.
1 tbl
The invention relates to medicine, namely to pharmacology and clinical pharmacology, and is intended for implementation in practice of pharmacologist and clinical pharmacologist to predict the possible membership of studied drugs to the substrate protein-conveyor -R (Pgp). as well as the use of finasteride as a positive control, increased activity Pgp when searching for substances of similar actions.
Pgp is ATP-dependent conveyor with a broad substrate specificity, controlling the pharmacokinetics of various compounds in physiological and pathological conditions, preventing penetration and accelerates the excretion of lipophilic substances through membranes of different cells [1].
There is a method of modeling of induction of functional activity of Pgp in the clinic on volunteers to study the possible participation of protein-conveyor in the pharmacokinetics of by introducing in a dose of 600 mg once a day for 7 days [2]. in a dose of 300 mg twice daily for 7 days was proposed as a model of increased activity Pgp PA volunteers in order to use it as a positive control for the search of potential inducers conveyor [3].
There is a method of modeling induction of functional activity of Pgp on patients with schizophrenia, the introduction of drugs Hypericum perforatum to research on this background, the pharmacokinetics of atypical neuroleptic clozapine [4].
There is a method of modeling of induction Pgp experiment in rats to create a positive control increased functional activity of protein-conveyor by a two-week introduction to animals extract of Hypericum perforatum in a dose of 15 mg/kg / day [5].
However as an inductor used in clinical practice, is characterized by significant toxicity [6], namely undesirable effect on the liver, kidneys, gastrointestinal tract, the blood system, development of allergic reactions. Studies on volunteers involve ethical issues, is subject to the permission of the ethics Committee, hospitalization volunteers in the intensive care unit for round-the-clock control over the state and hourly blood many times during the day. Products of vegetable origin are complex dosing, connected with the problem of standardization. Rats as an object of study (test-system) are not suitable for evaluation of the functional activity of Pgp is one of the modern, informative and popular methods - by means of analysis of marker substrates protein-conveyor.
There is a method of modeling of induction functional activity Pgp PA cell culture LS-180 to analyze the possible impact of the activity Pgp PA development of Alzheimer's disease through the introduction of rifampicin, dexamethasone, verapamil, , beta-estradiol and [7].
However, working with cell culture associated with considerable technical difficulties, require expensive laboratory equipment, so the technique is not available to most laboratories.
Was not found information on the use of finasteride to modeling of induction of Pgp in rabbits.
Finasteride-4-azo-3- inhibitor 5α-reductase type II enzyme, localized on the nuclear membrane of cells and transforming testosterone to dihydrotestosterone - key responsible for the development of benign prostatic hyperplasia and androgenetic alopecia. Finasteride is distributed but throughout the body, however, due to the specificity of action of the substance on 5α-reductase, which in high concentrations is contained only in prostatic tissue, skin of the head and genitals, side effects of other body systems males occur rarely [8], and women are practically not be stated in relation to low activity of the enzyme in the female body.
The aim of the invention was to create such a model of the induction of functional activity of Pgp, which does not create ethical problems, was not accompanied by the manifestation of side effects of substances in the study on human volunteers, and when studying the animals would be methodologically justified and does not require expensive laboratory equipment, materials and components for research on cell cultures.
The task is achieved by the fact that as an inducer of Pgp selected inhibitor 5α-reductase inhibitor finasteride, safe and economically accessible drug is administered orally once daily 14-day course at a dose of 0,225 mg/kg in the form of a suspension in olive oil, and as adequate and convenient test systems are used rabbits.
Description method
To solve this task we carried out an experiment on 6 rabbits sexually Mature male Chinchilla breed, average weight 3500-4300, Finasteride was administered to the animals within 14 days intragastric dose 0,225 mg/kg body weight in the form of a suspension in olive oil. The functional activity of Pgp was determined by analysis of the dynamics of plasma concentration , marker substrate protein-conveyor. Feksofenadin was chosen as an example Pgp substrates in connection with the fact that his depends solely on Pgp.
Feksofenadin (Drug 180 mg; manufacturer: Aventis Pharma, Italy) was injected once intragastric tube at the dose of 67.5 mg/kg of animal body weight before and after the 14 day of finasteride [9]. Blood samples were taken in the amount of 5-7 ml of regional Vienna rabbit ear in through 1, 2, 3, 4, 5, 6, 8, 12 and 24 hours after a single intragastric administration , centrifuged for 10 minutes at 3000 rpm, plasma stored at -28°C until analysis [10].
Contents in blood plasma was determined by HPLC PA chromatograph «Stayer» (Russia) with UV detector and reversed-phase column Coulter» 4,6*250 mm, grain size 5 microns. Extraction and marker substrate carried out by the method of V. et al. in own modifications. Analysis performed at a wavelength of 220 them and speed of the mobile phase 1 ml/min
Elution was performed mobile phase with the following composition (200 ml): 133,7 ml bidistilled water containing 2,33 ml of glacial acetic acid and 0,936 ml brought to pH 4,3 and 64 ml of acetonitrile. Retention time peak was 12,31 minutes
As extractants for liquid-liquid extraction used dichloromethane, ethyl acetate, and diethyl ether. The coefficient of extraction from plasma was 64%.
The obtained data are presented as the arithmetic mean and standard deviation, which in the case of the normal distribution of the characteristic or in the form of median, upper and lower quartile - if the distribution of data differed from the normal (table №1).
options was calculated using the program Kinetica 5.0.
A significant decrease in median values of C max on 13,63% (p} a 0.05), the AUC 0-t 30,37% (p} a 0.05). AUC 0-OO , 47.45% (p} a 0.05), the average values of T ½ on 65,16% (p} a 0.05), the MRT on 59.43% (p} a 0.05) and higher average values of K el on 131,88% (p} a 0.05) and Cl on 104,45% (p} a 0,05) 1 marker substrate Pgp - when prescribing finasteride in the dose 0,225 mg/kg course of 14 days compared with the original values testifies to an accelerated withdrawal of the marker substrate, which may be evidence of inducing the influence of finasteride PA functional activity of Pgp.
Use of the proposed method for modeling the state of induction of functional activity of Pgp on rabbits allows the use of finasteride as a positive control, increased functional activity of the protein Transporter when searching for substances of similar actions, and to predict potential Pgp substrates of medicinal substances at the stage of preclinical studies.
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The method of modeling of induction of functional activity of glycoprotein-R finasteride in the experiment, including the introduction of drug-inductor, characterized in that in the capacity of such drug use finasteride, which is when the experiment rabbits administered intragastrically in the form of a suspension in olive oil at a daily dose of 0,225 mg/kg of animal body weight within 14 days.