[Metabolic remodeling and the alteration of related receptors expressions in failing heart].

OBJECTIVE: To explore the metabolic remodeling and its correlative mechanisms in human failing heart by contrasting the content of substrate, the activity of correlative enzyme and the mRNA and protein expression of beta(3)-adrenoceptor and peroxisome proliferator-activate receptor alpha (PPARalpha). METHODS: Cardo ac tossie samples were talem from 20 patients with heart failure of valvular heart disease and undergoing valvuloplasty operation as well as 6 subjects being killed in accidents (as control). The levels of free fat acid (FFA) and the activity of succinate dehydrogenase (SDH), Na(+)-K(+)-ATPase and Ca(2+)-Mg(2+)-ATPase of the myocardial tissue were measured. Protein and mRNA expression of beta(3)-adrenergic receptor and peroxisome proliferator-activated receptor alpha (PPARalpha) in myocardial tissue were analyzed using reverse transcriptase-polymerase chain reaction and Western-blot respectively. RESULTS: In the failing hearts, the contents of FA and expression of beta 3 adrenoceptor mRNA and protein were obviously higher than those in the control group, the activity of SDH, Na(+)-K(+)-ATPase, Ca(2+)-Mg(2+)-ATPase and expression of PPARalpha mRNA and protein were on the contrary. CONCLUSION: The human failing myocardium is characterized by metabolic remodeling and it maybe concerned with the upregulation of beta3 adrenoceptor and downregulation of PPARalpha.

[Expressions of beta(3)-adrenoceptor and peroxisome proliferator-activated receptor alpha in human failing heart].

OBJECTIVE: To explore the changes on the content of substrate, the activity of correlative enzyme and the mRNA and protein expressions of beta(3)-adrenoceptor and peroxisome proliferator-activated receptor alpha (PPARalpha) in human failing heart. METHOD: Papillary muscles from 20 patients with heart failure during mitral valves replacement and 6 control subjects died of non-cardiac accidents were obtained and free fat acid (FFA), lactic acid (LD) and the activity of Na(+)K(+)-ATPase and Ca(2+)Mg(2+)-ATPase, protein and mRNA expressions of beta(3)-adrenergic receptor and PPARalpha were measured. RESULT: In the failing heart, the contents of fat acid, LD and expression of beta(3)-adrenoceptor mRNA and protein were significantly higher while the activity of Na(+)K(+)-ATPase and Ca(2+)Mg(2+)-ATPase, expressions of PPARalpha at mRNA and protein levels were significantly lower than those in control myocardium. CONCLUSION: Metabolic remodeling (upregulation of beta(3)-adrenoceptor and downregulation of PPARalpha) might contribute to the pathophysiology of heart failure.

[The relationship between expressions of beta1-, beta2-, beta3-adrenoceptor mRNA of myocardium and cardiac function in patients with heart failure].

OBJECTIVE: To investigate the alteration of expressions of beta(1)-, beta(2)-, beta(3)-adrenoceptor mRNA in human myocardial tissue and the relation between their expressions and cardiac function in patient with heart failure. METHODS: The mRNA expressions of beta(1)-, beta(2)- and beta(3)-adrenergic receptors in myocardial tissue were analyzed by using the reverse transcriptase-polymerase chain reaction in 24 patients with heart failure of valvular heart disease and 5 control subjects. RESULTS: Beta(1)-adrenergic receptor mRNA expressions in myocardium were significantly lower in patients with heart failure than those in control subjects, and progressively reduced with aggravation of heart function. By contrast, beta(3)-adrenoceptor mRNA expressions were significantly higher in patients with heart failure than those in controls, and progressively elevated with aggravation of cardiac function. No difference was observed in beta(2)-adrenergic receptor among all groups. CONCLUSION: The changes of beta-adrenergic receptor mRNA expression are associated with the severity of heart failure.

[Effects of topographic factors on the distribution patterns of ground plants with different growth forms in montane forests in North Guangdong, China].

By using canonical correspondence analysis (CCA), this paper studied the effects of small-scale topographic changes on the distribution patterns of ground plants with different growth forms in the montane evergreen broad-leaved forest in Chebaling National Nature Reserve of North Guangdong, China. It was observed that slope aspect, slope grade, and slope position had significantly integrative effects on the distribution patterns of four growth form ground plants (fern, liana, herb, and shrub). Slope aspect had significant effects on the distribution patterns of all four ground plants but slope position didn't have, whereas slope grade only affected the distribution pattern of shrub significantly. From shady slope to semi-shady slope, and to semi-sunny slope, the abundance of the four growth form ground plants decreased gradually, indicating that shade plants were dominant in the ground vegetation of subtropical montane evergreen broad-leaved forest. Most shrubs were shade-tolerant species, and their change patterns of richness and diversity with slope aspect were the same as the change pattern of abundance. Shrubs were sensitive to the change of slope grade, and richer on gentle slopes. In hilly and low mountains, slope position changed little, and had less effects on the distribution patterns of ground plants. At stand-level, horizontal topographic factor (slope grade aspect) had much greater effects on the distribution patterns of ground plants, as compared with vertical topographic factors (slope grade and slope position), which suggested that slope aspect was the major factor affecting the water and heat conditions in subtropical montane forest.