Humans ; Ion Channels ; Myocytes, Smooth Muscle ; metabolism ; physiology ; Pulmonary Artery ; metabolism ; physiology

Pulmonary artery hypertension (PAH) is a combination of factors caused abnormal pulmonary hemodynamics.Pulmonary vascular resistance (PVR) progressive as clinical features of PAH.In recent years,studies had shown that pulmonary artery smooth muscle cell membrane potassium channels at the time of PAH and pulmonary vasoconstriction (HPV) and vascular remodeling were closely related to potassium channel in the article on the role of PAH in progress of the study review.

Objective To explore the features of clinical manifestations and electrophysiology of spinal muscular atrophy(SMA) in children.Methods The clinical features and laboratory data were analyzed in 32 children with SMA,electromyography tests were carried out in 28 patients and the muscle biopsy were performed in 24 cases.Results The 32 cases were subdivided into 3 clinical groups,15 cases were SMAⅠ,12 cases were SMAⅡ,5 cases were SMAⅢ.They were all characterized by progressive muscle weakness associated with hyptonia and atrophy.The clinical distinction between SMAⅠto SMAⅢ reflected different age of onset and disease severity.All cases of SMAⅠhad symptoms of respiratory disability,only 1 case of SMAⅡ had paradoxical breathing and none of SMAⅢ had similarly symptoms.Electromyographic studies showed a pattern of denervation with no sensory involvement.The rate of spontaneous potential was 87%,with gentle strain,the duration of motor unit was extended(30%-150%) and the amplitude of it was increased(90%-450%),the motor nerve conduction velocity was reduced slightly in 28% patients.The muscle biopsy provided evidence of skeletal muscle denervation with groups of atrophy.Conclusions The clinical features,the changes of electromyography and the muscle biopsy are valuable for diagnosis of SMA.Respiratory management will prolong survival and improve the quality of life for these patients.

Objective To investigate the changes of plasma vasoactive intestinal peptide (VIP) and glucagon (Glu) in congestive heart failure and its clinical significance. Methods The levels of plasma VIP and Glu were measured with radioimmunoassay in 40 patients with congestive heart failure, including 15 patients with cardiac function in degree Ⅰ, 25 cases with cardiac function in degree ⅡⅣ, and 23 normal children who were served as controls. Results The levels of plasma VIP and Glu increased than that in normal control group[(43.22?5 48) ng/L vs(32.24?4.46) ng/L, P

Cardiovascular System ; GATA4 Transcription Factor ; metabolism ; Humans

95 mL/L O2) for 2 hours.The gross anatomical and histological changes(HE staining)in lungs were observed,VEGF mRNA expressions were studied by reverse transcription polymerase chain reaction(RT-PCR).Results Lungs of experimental groups represented edema,inaddition,punctiform,local and diffuse pulmonary hemorrhage were observed in groups of HH,HHR and HHRO2.Histopathological changes included pulmonary alveoli and interstitial edema,spacer breaking,pulmonary alveolidilating,fusion and hemorrhage,in which the most severe cases involved in group HHRO2.VEGF 188 mRNA expression increased significantly in group H and HH(P

950 mL/L for 2 hours.Gross anatomical changes and histological changes(HE staining)of lungs were observed,VEGF expression was detected by immunohistochemical method.Results Two rats in hypothermia-hypoxia group and 4 rats in rewarming-reoxygenating group died while none in control group.Lungs of hypothermia-hypoxia group and rewarming-reoxygenating group represented edema and punctiform,local and diffuse pulmonary hemorrahge.Histopathological changes included pulmonary edema,alveolar septum broken,pulmonary alveoli fusion and pulmonary hemorrahge.More severe pathological change could be found in rewarming-reoxygenating group.Optical density value of VEGF expression in 3 groups were 0.29?0.06,0.36?0.05,0.22?0.05,respectively,there were significant diffe-rences of VEGF expression between 3 groups(F=15.64 P

OBJECTIVETo investigate the electrophysiological changes of voltage-gate potassium channel (Kv) of pulmonary arterial smooth muscle cells of pulmonary arterial hypertension in rats induced by left to right shunt, and to analyze the role of Kv during the progress of pulmonary arterial hypertension.

METHODSForty male SD rats were randomly divided into three groups, group A (control, n = 10), group B (sham operated only group, n = 10), and group C (PAH model group, n = 20). Mean pulmonary artery pressure (mPAP) and right ventricular hypertrophy index (RVHI) of each rat were measured, single pulmonary artery smooth muscle cell (PASMC) was obtained by acute enzyme separation method (collagenase I plus papain) and the conventional whole-cell patch clamp technique was used to record resting membrane potential (Em), potassium ion current of voltage-gated potassium channel, the I-V curve between each 2 groups was compared, and correlation of each parameter was analyzed.

RESULT(1) The mPAP and RVHI of group C were significantly higher than those of group A and group B (P < 0.01, respectively). (2) The Em of group C [(-33.00 ± 4.09) mV] was significantly higher than that of group A [(-48.10 ± 4.54) mV] and group B [(-51.11 ± 3.66) mV], P < 0.01. (3) The peak current at +50 mV of voltage-gated potassium channel: in group C [(64.80 ± 8.40) pA/pF], it was significantly lower than that of group A [(120.85 ± 11.66) pA/pF] and group B [(118.03 ± 10.18) pA/pF] (P < 0.01, respectively). None of the parameters showed any significant difference between group A and group B (P > 0.05 for all comparisons). (4) Compared with group A and group B, the I-V curve of group C significantly downward shifted (P < 0.01, respectively). The difference in I-V curve between group A and group B was not significant, P > 0.05. (5) The correlation of resting membrane potential and mPAP and RVHI had significantly positive correlation (P < 0.001, respectively); but the correlation of membrane current, membrane current density and mPAP, RVHI and resting membrane potential had significantly negative correlation (P < 0.001, respectively).

CONCLUSIONDuring the formation process of left-to-right shunt induced pulmonary arterial hypertension, function of Kv channel was inhibited, suggesting that Kv channel may be the mechanism of pulmonary arterial hypertension induced by left-to-right shunting.

Animals ; Hypertension, Pulmonary ; metabolism ; physiopathology ; Male ; Muscle, Smooth, Vascular ; metabolism ; Patch-Clamp Techniques ; Potassium ; metabolism ; Potassium Channels, Voltage-Gated ; metabolism ; Pulmonary Artery ; metabolism ; physiopathology ; Rats ; Rats, Sprague-Dawley