Relation of abnormal gallbladder arterioles to gallbladder emptying in patients with gallstone and diabetes mellitus

BACKGROUND: Diabetes mellitus is thought to be related to gallstone formation in emptying the gallbladder. Diabe- tes mellitus may lead to many changes in microarterioles and micronerves; the aim of this study was to investigate the abnormality of arterioles in the gallbladder and its rela- tion to gallbladder hypomotility in patients with gallstone and diabetes mellitus. METHODS: Thirty patients with simple gallstones and 30 patients with gallstones and diabetes mellitus were analy- zed , and their gallbladder emptying function was measured with B ultrasound before operation. After operation, the arterioles of the gallbladder rinsed with periodic acid-schiff (PAS) reagent in photos were used for analysis of the tu- blar area and stereo system with the Beihang CM-2000B biological and medical photo system. RESULTS: In patients with gallstones and diabetes mellitus, the gallbladder emptying function was significantly im- paired, the area ratio of the arteriole wall to whole arte- rioles in cross section was significantly higher than that in patients with simple gallstones (0.81 ±0.09 vs. 0.58±0.15, P < 0. 01), and the average sound density was also higher (0.41 ±0.07 vs. 0.30 ±0.12, P<0.01) in patients with gall- stones and diabetes mellitus than in those with simple gall- stones. The size of arterioles (diameter) was not signifi- cantly related to the area ratio (P >0.05). CONCLUSION: In patients with diabetes mellitus, the se- dimentation of PAS positive material in the wall of arte- rioles leads to the stenosis of arterioles. It is probably con- tributive to hypomotility of the gallbladder.

Pravastatin alleviates lipopolysaccharide-induced placental TLR4 over-activation and promotes uterine arteriole remodeling without impairing rat fetal development

Preeclampsia is associated with over-activation of the innate immune system in the placenta,in which toll-like receptor 4（TLR4） plays an essential part.With their potent anti-inflammatory effects,statins have been suggested as potential prevention or treatment of preeclampsia,although evidence remains inadequate.Herewith,we investigated whether pravastatin could ameliorate preeclampsia-like phenotypes in a previously established lipopolysaccharide（LPS）-induced rat preeclampsia model,through targeting the TLR4/NF-κB pathway.The results showed that pravastatin reduced the blood pressure [maximum decline on gestational day（GD） 12,（101.33±2.49） mmHg vs.（118.3±1.37） mmHg,P〈0.05] and urine protein level [maximum decline on GD9,（3,726.23± 1,572.86） μg vs.（1,991.03 ±609.37）μg,P〈 0.05],which were elevated following LPS administration.Pravastatin also significantly reduced the rate of fetal growth restriction in LPS-treated rats（34.10% vs.8.99%,P〈0.05）.Further pathological analyses suggested a restoration of normal spiral artery remodeling in preeclampsia rats by pravastatin treatment.These effects of pravastatin were associated with decreased TLR4/NF-κB protein levels in the placenta and IL-6/MCP-1 levels in serum.Additionally,no obvious abnormalities in fetal liver,brain,and kidney were found after administration of pravastatin.These results provide supportive evidence for use of pravastatin in preventing preeclampsia.

Chronic Pulmonary Infection Caused by Mycoplasma Pneumoniae Leading to Pulmonary Arteriole Remodeling and Pulmonary Hypertension in Rats

The pulmonary arteriole remodeling in Wistar rats with respiratory infection induced by mycoplasma pneumoniae was observed using light microscopy and morphometry. The pulmonary artery pressure(PAP) and index of right ventricular hypertrophy (RVHI) were measured. The intimal and medial hypertrophy can be seen in the pulmonary arterioles, leading to vessei wall thickening and narrowing of the lumina. The total number of the pulmonary arterioles decreased (P <0.01) , and both pulmonary hypertension (Ppa 4.11±0. 19 kPa) and right ventricular hypertrophy (RVHI=34.96±3. 91%) occurred. In addition, an interstitial pulmonary fibrosis (IPF) was found, in which the content of collagen in the lung tissue changed, i. e. , type Ⅰcollagen increased whereas type Ⅲ one decreased, and the ratio of type Ⅰ collagen to type Ⅲ one increased. It suggested that respiratory infection induced by repeated MP may result in remodeling of pulmonary arterioles and are closely related to pulmonary hypertension.

Arterioles in cerebral amyloid angiopathy and vascular dementia

Background Small cerebrovascular lesions are one of the most important factors in cerebral amyloid angiopathy （CAA） and vascular dementia （VaD）. We analyzed the difference of arteriolar pathology between CAA patients （CAAs） and vascular dementia patients without CAA （VaDs）. Methods Ten deceased CAAs and twelve deceased VaDs were available for this study. Five deceased patients without known cerebrovascular diseases served as controls. These patients were all autopsy cases. All transversely cut arterioles in the gray matter and white matter with an external diameter equal to or larger than 30 um and with a maximum of 300 um were examined. The internal and external diameters of arterioles were measured. Results The external diameter of gray matter arterioles in the CAAs was significantly greater than in controls. In gray matter arterioles, the diameter of the lumen in VaDs was markedly smaller than in the CAAs, whereas there was no significant difference between CAAs and controls. CAAs and VaDs may cause remarkable thickening of the arteriolar walls in either white matter or gray matter. The sclerotic index of arterioles in VaDs was significantly greater than in CAAs and controls. Conclusions Stenosis of arterioles occurred in both CAA and VaD, but the tendency was greater in VaD. Arterioles of CAA were also expanded in gray matter, which may be related to lobar hemorrhage. The loss and/or degeneration of vascular smooth muscle cells was predominant in CAA, while the over-proliferation of vascular smooth muscle cells was areater in VaD.

Modeling columnar spatiotemporal dynamics of nitric oxide as a primary controlling element of arteriole dilation during neurovascular coupling

Although the mechanism of neurovascular coupling remains inadequately understood,physiological research has indicated that the dilation of arterioles located within the cerebral cortex column might represent the primary mechanism of hemodynamic response during neurovascular coupling.This study examined the spatiotemporal pattern of NO diffusion induced by functional stimuli at column spatial resolution.Our modeling makes it possible to explore the responses of mediating factors to functional stimuli from a four-dimensional view,which may lead the way to decoding the mechanism of neurovascular coupling.

Theoretical assessment of the Ca^2＋ oscillations in the afferent arteriole smooth muscle cell of the rat kidney

The afferent arteriole （AA） of rat kidney exhibits the myogenic response, in which the vessel constricts in response to an elevation in blood pressure and dilates in response to a pressure reduction. Additionally, the AA exhibits spontaneous oscillations in vascular tone at physiological luminal pressures. These time-periodic oscillations stem from the dynamic exchange of Ca^2＋ between the cytosol and the sarcoplasmie reticulum, cou- pled to the stimulation of Ca^2＋-activated potassium and chloride channels, and to the modulation of voltage-gated L-type Ca^2＋ channels. The effects of physiological factors, including blood pressure and vasoactive substances, on AA vasomotion remain to be well characterized. In this paper, we analyze a mathematical model of Ca^2＋ signaling in an AA smooth muscle cell. The model represents detailed transmembrane ionic trans- port, intracellular Ca^2＋ dynamics as well as kinetics of nitric oxide （NO） and superoxide （O2^-） formation, diffusion and reaction. NO is an important factor in the maintenance of blood pressure and O2^- has been shown to contribute significantly to the functional alternations of blood vessels in hypertension. We perform a bifurcation analysis of the model equations to assess the effect of luminal pressure, NO and O2^- on the behaviors of limit cycle oscillations.

Self-Similarities of Pulmonary Arterial Tree and a New Integrated Model of Pulmonary Circulation with the Name of Fractal Phasic Perfusion (FPP) Model

Pulmonary arterial hypertension (PAH) has become an important topic of basic and clinical research in recent years. Morphologic researches have shown that specific PAH-lesions are located in the lobular small muscular arteries and correlate with hemodynamic measurements. However, it still remains to be shown how pathological changes of the small arteries in the lobule develop to PAH. Based on both fractal properties of pulmonary arterial tree and asynchronous phasic contractions of lobular arterial muscles under the evenness of the pulmonary capillary pressure (PCP) in the lung, the author has constructed an integrated model of pulmonary circulation which has produced a mathematical relationship between the mean pulmonary arterial pressure (MPAP) and the cardiac output (CO). By use of the expression between MPAP and CO, it has been able to explain the pathogenesis of PAH in terms of statistical changes among regional and temporal perfusions in the lung. In order to detect clinically the early stage of PAH, the author has suggested that it is important to establish the pulmonary functional imaging of regional and temporal perfusions.

Expression of adrenomedullin and its receptor in lungs of rats with hypoxic pulmonary hypertension

OBJECTIVE: To investigate the role of adrenomedullin (AM) in the development of hypoxic pulmonary hypertension (HPH), and to assess the expression of AM and adrenomedullin receptor (AMR) in the lungs of rats with HPH. METHODS: We exposed 10 rats to normobaric hypoxic conditions for 3 weeks to establish rat model of pulmonary hypertension; and 10 other rats were used as normoxic controls. Mean pulmonary arterial pressure (mPAP) was measured by a right cardiac catheterization. The thickness of pulmonary arterioles was measured by a computerized image analyzer. We used the reverse transcription-polymerase chain reaction (RT-PCR) to assess the change of expression of AM and AMR in lung of HPH rat model. RESULTS: Compared with the control group, hypoxic rats developed remarkable pulmonary hypertension, increment in the thickness of pulmonary arterioles and right ventricular hypertrophy (P

The ATP sensitive K^+ channel and membrane potential in the pathogenesis of vascular hyporeactivity in severe hemorrhagic shock

To elucidate the mechanism of vascular hyporeactivity following severe hemorrhagic shock (HS) by studying the changes of ATP sensitive potassium channels (K ATP ) properties and membrane potential of mesenteric arteriolar smooth muscle cells. Methods: Single channel currents were studied on cell attached and inside out patches of enzymatically isolated mesenteric arteriolar smooth muscle cells (ASMCs). Membrane potentials of arteriolar strips and ASMCs were recorded by intracellular membrane potential recording method and confocal microscopy, respectively. Results: K ATP channels in ASMCs were activated, which induced smooth muscle hyperpolarization following vascular hyporeactivity in HS. Conclusions: Hyperpolarizing effect of K ATP channel activation plays an important role in low vasoreactivity during severe hemorrhagic shock.