[Adverse cardiovascular effects of antiretrovirals in female mice during gestation].

Objective: To evaluate the effects of antiretrovirals on cardiovascular function and some biochemical indexes in gestational female rats. Methods: Nineteen 9-week-old female and six 10-week-old male SD rats were divided into normal control group (CON) and highly active antiretroviral therapy group (HARRT), 9/10 female rats and 3 male rats were combined into one cage, totally 2 cages. Female rats in CON group were intragastrically given with normal saline (NS, 10 ml/kg) every morning and evening, while female rats in HARRT group were treated with equal volume antiretrovirals (AZT 31.25 mg/kg + 3TC 15.63 mg/kg + LPV/r (41.67/10.42) mg/kg) for 3 months. The body weight and survival rate of female rats were recorded. Echocardiography and multichannel physiological recorder were used to detect arterial blood pressure and cardiac hemodynamic parameters. The levels of blood glucose, blood lipids, myocardial enzymes and liver enzymes were detected by corresponding kits. Myocardial collagen fibers were observed by Masson staining and the ultrastructure of myocardial cells were observed by transmission electron microscopy. Results: All female rats in CON group survived (9/9), while only 6 rats in HARRT group survived (6/10). Compared with CON group, the body weight of female rats in HAART group was decreased significantly(P＜0.01); the levels of left ventricular end diastolic diameter (LVDd), interventricular septal thickness (IVST), thickness of left ventricular posterior wall (LVPWT) , left atrial diameter (LAD) and arterial diastolic pressure were increased significantly (P＜0.05); the level of LVP+dP/dtmax was decreased (P＜0.01). The levels of triglyceride, creatine kinase, and glutamic oxaloacetic transaminase were decreased (P＜0.05 or P＜0.01), while the level of glucose was increased (P＜0.05). The collagen fibers were increased in myocardial tissue, and ultrastructure of myocardial cells was abnormal. Conclusion: Antiretrovirals during gestation can cause cardiovascular diseases in female rats.

[Water-air Carbon Dioxide Exchange and Nutritional Controls in a Typical Karst River].

To explore water-air carbon dioxide (CO2) exchange and its nutritional controls in karst rivers, water sampling and analyses were conducted in the Furong River as a representative karst river system. Regional hydrometeorological characteristics, carbonate system parameters, total organic carbon (TOC), nutrients and their stoichiometric ratios, and the riverine pressure of aqueous CO2 (pCO2) and its couplings to trophic status were analyzed. The results showed that gas transfer velocity of CO2 (k) varied between 2.71 and 13.0 m·d-1. Riverine pCO2 varied from 78.5 Pa to 21491.2 Pa and was significantly higher in the tributaries than the main stem. Riverine TOC, total nitrogen (TN), and total phosphorus (TP) concentrations were (302.8±50.1), (128.9±67.9), and (0.65±0.98) µmol·L-1, respectively, demonstrating the trophic status of P-limitation. Riverine pCO2 was tightly linked to P-related parameters, suggesting that in-situ metabolism triggered aquatic CO2 supersaturation. Water-air CO2 flux (F) averaged (534.5±801.4) mmol·(m2·d)-1 in the Furong River, which is higher than most of the world's rivers, and thus indicates high potential CO2 emissions.

[Establishment of rat model of type 2 diabetes complicated with hypertension].

OBJECTIVE: To establish type 2 diabetic model in rats complicated with hypertension. METHODS: Sixty five SD male rats were divided into normal control group, 1%NaCl water-treated group, 20 mg/kg STZ-1% NaCl-treated group, 30 mg/kg STZ-1%NaCl-treated group and 40 mg/kg STZ-1% NaCl-treated group according to random digit table(n=13).Except that rats in the normal control group were fed with ordinary diet, rats in the other groups were fed with high-fat diet for 4 weeks, then maintained with free access to rat chow and 1% NaCl drinking water for 9 weeks. In addition, rats in streptozotocin(STZ) groups were received STZ at a different dose(20 mg/kg, 30 mg/kg, 40 mg/kg)respectively by intraperitoneal injection at the end of the fourth week. The experimental period lasted 13 weeks. During the study, the general condition, body weight, average food intake, blood glucose, blood pressure, blood lipids and plasma insulin levels of each rat were tested. RESULTS: After STZ injection, tests showed body weight was significantly reduced (P<0.05), average food intake and fasting/random blood glucose level were increased significantly (P<0.05); blood pressure was obviously risen (P<0.05)and the average value of systolic blood pressure was reached 150 mmHg into hypertensive stage at the 4th week and stable at 150~170 mmHg for five weeks(before the end of experiment); the level of plasma insulin was higher significantly (P<0.05), the level of plasma triglyceride(TG)was descended significantly (P<0.05)at the 13th week of the experimental period, each of which was only in 30 mg/kg STZ-1% NaCl-treated rats and 40 mg/kg STZ-1% NaCl-treated rats as compared with non-treated rats or 1% NaCl water-treated rats. CONCLUSIONS: The method that the rat was fed with high-fat diet for 4 weeks, then, received intraperitoneal injection of 30~40 mg/kg STZ combined with feeding 1% NaCl drinking water, which can induce insulin resistance in rats with type 2 diabetes mellitus and hypertension.