BACKGROUND: Angiotensin Ⅱ (Ang Ⅱ) can induce cardiac hypertrophy and platelet-derived growth factor(PDGF) also stimulates cardiac hypertrophy. Is AngⅡ responsible for the pathogenesis of cardiac hypertrophy by inducing PDGF receptor expression?OBJECTIVE: To investigate the effect of mitogen activated protein kinase (MAPK) on the role of cardiac hypertrophy induced by Ang Ⅱ in cardiac myocytes so as to provide theoretical basis for clinical prevention and cure of cardiac hypertrophy.DESIGN: Controlled experimental study taking cardiac myocytes of cultured neonatal rats as subjects.SETTING: Department of pathophysiology in a university.MATERIALS: The experiment was completed in the Department of Pathophysiology, Medical College of Peking University. A total of 80 Wistar rats of either gender, aged 1 - 3 days, were provided by the Animal Center of Medical College, Peking University. Their hearts were removed for myocyte culture in the Cell Culture Laboratory.INTERVENTIONS: The cultured neonatal rat cardiac myocytes treated with 10-7mol/L Ang Ⅱ were Ang Ⅱ group, and those preincubated with 10-5mol/L PD98059(an antagonist of MAPK) for 30 minutes and then treated with Ang Ⅱ were PD98059 group. Cardiac myocytes of normal neonatal rats were as control group. The expression of PDGF-β was detected by western blot at 24 hours.MAIN OUTCOME MEASURES: Content of PDGF-β receptor in neonatal rat cardiac myocytes.RESULTS: The expression of PDGF-β receptor induced by Ang Ⅱ at neonatal rat cardiac myocytes markedly increased at 24 hours (432.41 ± 54.08) compared with that of control group(197.65 ± 44. 10) ( q = 6.77, P< 0.01 ). PDGF-β receptor expression of PD98059 group(317.2 ± 21.12) decreased compared with that of Ang Ⅱ group(q = 3.91, P < 0.05) .However, the expression did not return to the level of control group, and there was significant difference between PD98059 group and control group( q= 3.85, P <0.05).CONCLUSION: The results indicate that angiotensin Ⅱ promotes cardiac hypertrophy through inducing expression of PDGF receptor, in which mitogen activated protein kinase participates in. Maybe it is another important mechanism for Ang Ⅱ -induced cardiac hypertrophy. The results can provide experimental data for the primary and secondary prevention in heart rehabilitation.

Adolescent ; Adult ; Aged ; Case-Control Studies ; Central Nervous System Neoplasms ; cerebrospinal fluid ; diagnosis ; Child ; Female ; Humans ; Hyaluronan Receptors ; cerebrospinal fluid ; Leukemia ; cerebrospinal fluid ; Male ; Middle Aged ; Young Adult

AIM: To investigate the crosstalk between angiotensin Ⅱ (AngⅡ)-mediated and platelet-derived growth factor (PDGF)-mediated signal transduction in vascular smooth muscle proliferation.METHODS: A model of renal hypertension was made by two kidney/one-clip operation. Level of PDGF receptor ? subunit of aorta was measured by Western Blot analysis. The effect of Ang Ⅱ on PDGF receptor ? subunit expression was investigated in culture rat aortic vascular smooth muscle cells (VSMC).RESULTS: Systolic blood pressure obviously increased at 8th week after operation, whereas the level of PDGF receptor ? subunit of aorta significantly increased by 126.6% ( P

Objective　Recently,it was reported the analy sis of bone free radical by using electron spin resonance (ESR),so this article aimed to determine the changes of bone free radical in fluoresis rats.Methods　To analyze the free radical level of bone in fluoresis rats fed with different dose of calcium by ESR method.Results　The free radical of bone in the group of low ca lcium level and the group low calcium+fluorides was higher than that in the cont rol group (P<0.01),but that in normal animal feeds (calcium-rich)+fluoride group was lower than that in the control group.Conclusions　Low doses of fluoride did not resulted in the increase of free radical in calcium-rich condition at short time,but at low calcium condition,fluoride could increase the level of free radical,these suggested that simple overdose of fluoride did not change the level of free radical of bone.

Background The extraocular muscles (EOMs) Pulley is considered as the functional origins of the recti EOMs,it is determinants of ocular motility.Objective The structure of the connective tissue around EOMs in cat was studied,and the role of EOMs Pulley to ocular movement was investigated.Methods Five adult cats were involved.The gross anatomy of an orbit in each cat was observed.The other orbit was processed with paraffin imbedding and coronal serial sections.A murine monocolonal antibody to α-smooth muscle actin (α-SMA) was used to show smooth muscle,while Masson trichrome stain was used to show muscle and collagen,and Weigert stain to show elastin.Results An encircling ring of collagen circled EOM was thin and connected to the orbital layer of muscle fiber loosely.Less elastin fibers and little smooth muscle cells were embedded in the collagen ring and connective band.Collagen ring around medial rectus and the connective band between medial rectus and inferior rectus was not more significantly developed than other bands.Conclusions The connective tissue around EOMs in cat may be related to its function of ocular movement,which is not developed.

Objective To study the clinical features of children with rotavirus enteritis complicated with respiratory infection.Methods The clinical features of 32 children with rotavirus enteritis were evaluated retrospectively complicated with respiratory infection (respiratory infection group) and 37 children with rotavirus enteritis complicated without parenteral infection (control group).Results 1. The respiratory symptoms became alleviative as the alimentary symptoms changed for better. 2. Duration of diarrhea weve(7.06?1.50)d in respiratory group was significantly longer than that in control group (4.73?1.31)d (t=6.90 P

Catechols ; urine ; Chromatography, High Pressure Liquid ; methods ; Electrochemistry ; methods ; Humans ; Hydroquinones ; urine

AIM: To investigate the crosstalk between angiotensin Ⅱ (AngⅡ)-mediated and platelet-derived growth factor (PDGF)-mediated signal transduction in vascular smooth muscle proliferation.METHODS: A model of renal hypertension was made by two kidney/one-clip operation. Level of PDGF receptor β subunit of aorta was measured by Western Blot analysis. The effect of Ang Ⅱ on PDGF receptor β subunit expression was investigated in culture rat aortic vascular smooth muscle cells (VSMC).RESULTS: Systolic blood pressure obviously increased at 8th week after operation, whereas the level of PDGF receptor β subunit of aorta significantly increased by 126.6% (P＜0.05) in 2K1C rats compared with control group. The expression of PDGF receptor β subunit in cultured VSMC stimulated by AngⅡ was higher than that of control by 192.74%(P＜0.01). The effect of AngⅡ was inhibited remarkably by pretreated with losartan, a kind of specific AngⅡ receptor 1 (AT1) subtype antagonist and U73122, a kind of phospholipase C inhibitor. The effect was partly blocked by PD98059, which inhibit the activity of mitogen-activated, ERK-activating kinase (MEK).CONCLUSION: AngⅡ-induced PDGF receptor β subunit expression is regulated by the AT1 and its downstream signal molecule-PLC and ERK, might participate in the intracellular signal transduction pathway.

AIM: To investigate the role of G?q/11-mediated signal transduction pathway in cardiac hypertrophy induced by angiotensin II (AngII). METHODS: Renal hypertension was performed by placing a sliver clip around the left renal artery(2K1C). Hemodynamic parameters, the ratio of left ventricular weight to body weight, the AngII contents and the activities of phospholipase C (PLC) in myocardium were measured at 1st, 2nd, 4th and 8th week after operation, respectively. The levels of G?q/11 were assayed by Western blot analysis. -leucine incorporation and levels of G?q/11 were measured in cultured neonatal rats ventricular myocyte after AngII stimulation. RESULTS: In 2K1C group, blood pressure and the ratio of left ventricle of heart to body weight were significantly increased compared with sham group between 2nd to 8th week. AngII content increased from 1st to 8th week after operation. Compared with the sham group, levels of G?q/11 in 2K1C group increased by 25.0% and 35.8% at 4th and 8th week( P

Objective:To investigate the features of gait disorders in patients with idiopathic normal pressure hydrocephalus(iNPH).Methods:Clinical data of 42 patients diagnosed with iNPH admitted to the neurological department of Aviation General Hospital from March 2017 to July 2020 were consecutively collected.The features of gait disturbance and activity of daily living were retrospectively studied.Results:Of the 42 patients, 29 cases(69%)were males, aged(73.0±8.3)years, and 13 cases were females, aged(73.0±8.3)years old.The mean course of disease was(3.5±3.0)years.There were 90.5% of patients(38/42)complained of gait disorders, and 61.9%(26/42)had fall histories.All patients had gait abnormalities.The time for 3m-Timed Up and Go(TUG)test were(27.8±17.0)seconds, and the proportion of patients with the time for 3m-TUG less than 10 seconds, 10~20 seconds and more than 20 seconds were 5.9%(2/34), 35.3%(12/34)and 58.8%(20/34), respectively.In the 10-meter walking test, 8 patients needed assistance.Of the 34 patients who could walk independently, 94.1%(32/34)had tandem walking disturbed and tendency toward falling, 76.5%(26/34)had turning disturbed, 44.1%(15/34)had wide based stride and small steps, 29.4%(10/34)had trunk balance disturbed, 23.5%(8/34)had reduced foot-floor clearance, and 8.8%(3/34)had start hesitation, 97.6%(41/42)had abnormal step counting and 90.5%(38/42)had abnormal time evaluation.The proportion of patients with activity of daily living(Barthel Index)scores of(mild dependence), moderate dependence and severe dependence were 71.4%(30/42), 28.6%(12/42)and 0%(0/42). Of the 30 patients with mild dependence, 56.7%(17/30)had fall histories.Conclusions:In our study, all patients have gait dysfunction, which causes some impact on activity of daily living and a higher risk of falls.Gait slowness, tandem walking disturbed, turning disturbed, tendency toward falling, wide based stride and small steps are the most involved gait characteristics.Early assessment of gait disorders is of great significance in early diagnosis and the prevention of falls and living ability decline.