动物实验,高血压 z-bo 2020-09-03 435

　　Background: Hypertension is one of the most common medical problems during pregnancy, affecting 6-8% of pregnant women. Many pregnant women with high blood pressure are healthy babies and are not a serious problem, but high blood pressure increases maternal and perinatal risks. For example, the mother suffers from preeclampsia, which may affect the placenta and the pregnant woman’s kidneys, liver and brain, leading to fetal complications such as underweight and premature birth. In the most severe cases, preeclampsia can develop into convulsions and life-threatening diseases. However, drug treatment for pregnant women can cause various developmental toxicity. Some drugs that lower blood pressure are considered safe during pregnancy. However, some of the most effective antihypertensive drugs are usually avoided during pregnancy, such as angiotensin converting enzyme (ACE) inhibitors and angiotensin receptor blockers (ARB). For example, Losartan has been designated by the FDA as pregnancy category D. This means that based on the side effects data, there is solid evidence that it affects the development of human fetuses. Fetal toxicity associated with ACE inhibitors and ARBs is related to the decrease of angiotensin II and the dysfunction of the renin-angiotensin system during fetal development. ACE inhibitors can cause fetal toxicity, including severe renal failure, neonatal anuria, skull ossification, fetal growth retardation, stillbirth, and dysfunction. Intrauterine exposure to drugs can prove fetal or neonatal toxicity, renal failure, and the use of ARB may cause fetal weight loss, kidney damage and even fetal death. display. In addition to the toxic effects of the drug itself, the distribution characteristics of the drug are directly related to the safety of the fetus and newborn. The large-scale distribution of the drug in fetus and breast milk is one of the key factors leading to fetal and neonatal toxicity, and poor distribution can lead to reduced toxicity. Placental migration and milk excretion are the hallmarks of ARB. The distribution of FMS in fetus or breast milk is unclear, which is the key to assessing the safety of FMS in pregnancy and breastfeeding. This study examined placental metastasis and lactation in pregnant and lactating rats. After intravenous infusion, we evaluated the pharmacokinetics of FMS in placenta, amniotic fluid, fetus and milk.

　　Method: Animal test: Female SD rats (8-10 weeks old, weight 250-330g), light/dark cycle animal facility for 12 hours, temperature 23±3℃, relative humidity 55±15%, air 10/h replacement 20 Times. There are 3 animals in each cage. FMS maternal-fetal transfer: At 16-17 days of gestation (GD), the fetus is large enough for analysis, intraperitoneal injection of Shutai 50 (20 mg/kg) to anesthetize female rats and polyethylene tubes. The vein and femoral artery are embedded in the neck. One day after recovery, FMS was dissolved in saline and injected through the jugular vein at doses of 2.70 and 5.50 mg/kg at rates of 0.17 and 0.34 mg/h/kg, respectively, with target concentrations of 100 and 200 g/ml. The initial IV bolus load and continuous IV infusion rate have been determined by multiplying the target steady state concentration (CSS) by the distributed steady state volume and FMS clearance, respectively. It can be administered without anesthesia. Blood was collected from the femoral artery before and 4, 8, 24, 28, and 32 hours after the operation. At each sampling, approximately 0.3 ml of blood was collected and mixed with an equal volume of heparinized saline (50 IU/ml). Centrifuge at 13000g for 5 minutes and store at -20°C until plasma sample analysis. Thirty-two hours after the start of the intravenous infusion, the animals were anesthetized by intravenous injection of Shutai (2 mg/kg) and sacrificed by cervical dislocation. Three samples of each tissue were sacrificed, such as placenta, amniotic fluid and fetus. After adding physiological saline, homogenize the placenta and fetus with a homogenizer. The samples are stored at -20°C until analysis. The average concentration of 24-32hdeFMS represents the steady-state plasma concentration. The tissue-plasma partition coefficient (KP) was calculated by dividing the steady-state plasma FMS concentration by the 32-hour average tissue FMS concentration. Lactation FMS: In the middle of lactation, from the 12th to 13th days of the lactation period (LD), under anesthesia, the female rat's internal jugular vein and femoral artery are injected with a polythene tube of Shutai 50 (20mg/kg). One day after recovery, FMS was dissolved in saline and injected through the jugular vein at doses of 2.70 and 5.50 mg/kg, the doses were 0.17 and 0.34 mg/h/kg, and the target concentrations were 100 and 200 g/ml. Do not fast when the dose has been reached. Blood samples were collected before dosing and at 4, 8, 24, 28, and 32 hours. After 32 hours of continuous intravenous infusion, intravenous injection of Shutai 50,2mg/kg under mild anesthesia was given to obtain milk. 30 minutes before breast milk sampling, 5 IU of oxytocin was injected subcutaneously to facilitate milk collection. Pull the nipple gently by hand to stimulate milk production and collect the milk in a polypropylene tube. The samples are stored at -20°C until analysis. The average concentration of 24-32hdeFMS represents the steady-state plasma concentration. Milk KP is calculated as the milk concentration 32 hours higher than the plasma FMS concentration. Determination of FMS concentration by liquid chromatography and mass spectrometry: The concentration of FMS in biological samples was determined by the previously reported LC-MS/MS method. Add 200 μL of acetonitrile and 50 μL of internal standard solution to 50 μl of thawed biological sample and vortex for 1 minute. The mixed sample was centrifuged at 15000G at 4°C for 10 minutes, and the supernatant was transferred to a polypropylene tube and diluted with an equal amount of distilled water. Inject 10 uL of liquid into the LC-MS/MS.

　　Result: Liquid chromatography-mass spectrometry combined with FMS: the detection limit of plasma, placenta, amniotic fluid, fetus and milk matrix is 0.5g/ml. The correct answer rate is 94.2-117.9% for plasma, 89.2-1111% for placenta, 87.7-116.9% for amniotic fluid, 89-110.7% for fetus, and 88.8-109.5% for milk. The accuracy of plasma, placenta, amniotic fluid, fetus and milk samples were 8, 12.3, 3.8, 10.4 and 8.5%, respectively. Placental transfer of FMS: When the steady-state concentration (CSS) of FMS in plasma of pregnant rats is 100g/ml and 200g/ml, the average concentration of FMS in plasma and tissues will change with time. The prediction interval of CSS is 10% and 90%, mainly because FMS has been cleared. The 10% and 90% prediction intervals of CSS are 81.4 and 138.6g/ml, respectively, and the target is 100g/ml (intravenous infusion, rate = 0.17 mg/h/kg) and 162.8 and 277.3g/ml, the target is 200g/ml (Intravenous drip, rate = 0.34 mg/h/kg). After the administration of FMS, the plasma FMS concentration increased rapidly, reaching 114.1±22.0 and 213±89.4g/ml. They are close to the expected target CSS = 100 and 200g/ml at 24 hours, respectively. There was no significant difference in FMS concentration after 24, 28 and 32 hours, indicating that the FMS concentration reached a steady state. 32 hours after administration, FMS concentration in placenta, amniotic fluid, fetus and plasma. The placental FMS concentration of the target dose group with CSS=200g/ml was 112.2±51.2g/g, and the placental FMS concentration of the group 7 with CSS=100g/ml was 4.9±24.5g/g. I proved it. The FMS mass concentration of the amniotic fluid in the CSS = 200g/ml and CSS = 100g/ml dose groups were 3.3±3 and 2.3±1.3 g/ml, respectively, and the fetal FMS mass concentration was 37.4±23.6 vs 19.2±4.8. done. Nanograms/gram. There was no statistically significant difference in tissue concentration between the CSS = 200g/ml and CSS = 100g/ml groups. Table 2 summarizes the average distribution coefficient (KP) from tissue to plasma. The partition coefficient between placenta and plasma (KP, placenta) is 44.6-59%, and the KP values of amniotic fluid and fetus are as low as 1.3-1.7% and 14.9-17%, respectively. The KP values of all tissues in the high-dose group and the low-dose group are comparable. This indicates that as the plasma concentration increases, the concentration of the tested tissue increases proportionally, and the placental metastasis of FMS is not sensitive to dose. LMS FMS during lactation: The target steady-state concentration (CSS) for 13-14 days after delivery is 100 and 200 g/ml. With FMS, the average concentration of FMS in plasma and milk will change over time. The Css prediction interval is 10-90%, and the plasma FMS concentration increases rapidly, approaching the target CSS of 100 and 200g/ml, and remains unchanged throughout the study. There was no statistical difference in plasma FMS concentration at each sampling time. 32 hours after administration, the plasma concentrations of 100 and 200g/ml groups were 126.4±49.3 and 198.8±40.8g/ml, respectively. The concentration of FMS in plasma and milk increased significantly in a dose-dependent manner. The plasma and milk FMS concentrations in the CSS = 200ng/ml group were significantly higher than those in the CSS = 100ng/ml group. The calculated plasma and plasma partition coefficient (KP) is 10.4-15.2%. Comparing the milk and plasma distribution coefficients between dose groups (100 vs. 200g/ml) showed that as the plasma concentration increased, the concentration in milk increased proportionally, while lactation was not affected by the dose. being shown.

　　Conclusion: This is the first report of fetal and neonatal FMS exposure. Our data show that the transfer rate of FMS to the fetus and breast milk is relatively lower than other ARBs. Further research is needed to evaluate the clinical impact of FMS transfer to fetus and breast milk, and to reveal the underlying mechanism of FMS in fetus or breast milk.