[Activation of transcription factor NF-κB in a rat model of cardiac fibrosis induced by ß-adrenoceptor stimulation].

OBJECTIVE: To establish a model of cardiac fibrosis induced by isoproterenol (ISO), the non-selective ß adrenoceptor agonist, injected subcutaneously for 7 days in rats, and to observe changes of transcription factor NF-κB in the model. METHODS: Male SD rats weighing 280-320 g were injected with ISO (0.25 mg/kg/d) subcutaneously for 7 days to induce cardiac fibrosis. The collagen volume fraction was determined by quantitative morphometry of picrosirius red stained left ventricular sections. Collagen types I/III and IL-6 mRNA expressions were analyzed by real time PCR. The pathological changes of the heart were investigated by Hematoxylin and Eosin staining. NF-κB was localized by immunohistochemistry (IHC) and phosphorylated NF-κB levels were assessed by Western blot analysis. RESULTS: Compared with the controls, ISO significantly elevated the sirius red stained area and collagen volume fraction (12.01±1.644 vs. 0.95±0.067, P<0.001). Similarly, ISO increased the mRNA expressions of collagen Iand collagen III of the heart compared with the controls (10.51±0.47 vs. 0.98±0.02,P<0.001 for collagen I; 9.58±1.33 vs. 1.02±0.02, P<0.001 for collagen III). The number of nuclei was increased and nuclear accumulation was presented in myocardial tissue induced by ISO. The mRNA expression of IL-6 increased in ISO group (1.64±0.18 vs. 1.04±0.07, P<0.01). ISO induced NF-κB nuclear translocation, accompanied by an increase in phosphorylation of NF-κB (10.83±2.05 vs. 1.05±0.27, P<0.001). CONCLUSION: We conclude that the model of cardiac fibrosis can be successfully induced by ISO injected subcutaneously for 7 days in rats and the activation of nuclear factor NF-κB increased by ß-adrenoceptor stimulation.

[Establishment of a FVB/N mouse model of cardiac hypertrophy by isoprenaline].

OBJECTIVE: To investigate the condition of isoprenaline (ISO)-induced cardiac hypertrophy in the FVB/N mouse. METHODS: ISO (30 mg/kg/d) was administered either by daily subcutaneous injection, or by continuous infusion via an implanted osmotic minipump. The mice in each mode of administration were randomly divided into two groups. For subcutaneous injection: the mice received ISO or saline through daily subcutaneous injection for 2 weeks. The mice for minipump: the mice received continuous infusion of ISO via an implanted osmotic minipump for 2 weeks, or received sham operation as the control to mimipump. The ratio of heart weight to tibia length (HW/TI), the diastolic left ventricular posterior wall thickness (dLVPW) were used to indicate cardiac hypertrophy. Interstitial fibrosis was examined with picrosirius red staining. RESULTS: ISO (30 mg/kg/d) administered by daily subcutaneous injection did not lead to cardiac hypertrophy or fibrosis in the FVB/N mice, and 50% of the mice died before the end point. The mice receiving ISO via minipumps showed significant increase in HW/TI [(10.60±0.40 ) mg/mm vs. (7.93±0.19) mg/mm,P<0.001] and dLVPW [(0.87±0.03) mm vs. (0.68±0.06)mm,P=0.0116]. ISO administered via minipumps did not induce cardiac fibrosis. All the mice in this group survived to the end point. CONCLUSION: ISO (30 mg/kg/d) administered by continuous infusion via a minipump for 2 weeks can lead to significant cardiac hypertrophy.

Preparing for the third millennium: the views of life informatics.

The chief aspects of this paper are the condition of the birth of life informatics and its tasks, basic concepts, principles, and structure. There are three phases of combining informatics with medicine: product, technological, and theoretic application of which the goals are respectively the informatization of numerical and word processing, data of medical treatment, and the knowledge of medicine. While reached the third phase we have dealt with two types of biological information, physical and nonphysical, i.e., body information (i.e., the information about body's components and structure), and life information (i.e., the information about life codes and life programs). Life informatics is a main branch of bioinformatics. It is a new member of the medical informatics family, and as such is younger than health informatics, nursing informatics, and dental informatics. It's task is to assist biologists and medical doctors to recognize and interfere the human life information procedure just as they are doing well with human body's matter and energy system. Its basic concepts are life information, life information medicine, and life information therapy. Its most important principles are information materialism, general informatics, and information determinism. Its main branches are biomolecule, cellular, organic, individual, and social informatics. In the third millennium, the life informatics will be a leading discipline in biology, medicine and informatics, which will gradually influence modern philosophy and other humanities.