Muscle Layer Of Blood Vessels Research Articles

The diagnosis and arthroscopic treatment of angioleiomyoma presenting loose body in the knee joint: two case reports

BackgroundAngioleiomyoma is a very rare benign solitary soft tissue neoplasm originating from smooth muscle layer of blood vessels. The tumor is usually located in the subcutis or the superficial fasciae, but less often in the deep fasciae, especially rare in the knee joint cavity. Diagnosis is frequently delayed or misdiagnosed as loose body or anterior knee pain because of its rare occurrence and poor awareness of physicians. Few studies have presented intra-articular angioleiomyoma and such cases become rarer and more difficult to diagnose when it presents as loose body.Case presentationTwo patients, a middle-aged man and an old woman, presented to our outpatient clinic with persistent anterior knee pain and both of them suffered from a solitary mass in the right knee that had slowly enlarged. One of two patients showed negative in the routine radiographic imaging and the other showed a “loose body” beside the lateral femoral condyle in the knee. MRI showed both a well-demarcated intra-articular mass of isointense signal to muscle on T1-weighted images and heterogeneous intensity on T2-weighted images. Their tumors were excised under arthroscopy finally, with the pathological results revealed vascular leiomyomas. They both recovered well with pain free after operation and no signs of recurrence were seen at the 7-year follow-up.ConclusionsThis case report illustrates the atypical locations of angioleiomyoma in the knee joint should arouse our attention and be included in the differential diagnosis of nodular lesions mimicking loose bodies.

Severe pre-eclampsia complicated by HELLP syndrome alterations in the structure of the umbilical cord (morphometric and immunohistochemical study)

The aim of this study was to evaluate the morphometric and immunohistochemistry in umbilical cords from patients with severe pre-eclampsia with and without haemolysis, elevated liver enzymes and low platelets (HELLP) syndrome. The patient and control groups were similar according to baseline obstetric characteristics. White blood cell count in patients with HELLP syndrome and the control group was significantly increased among patients with HELLP syndrome (p < 0.001). Morphometric examination and endothelial core length were significantly different between the groups. In the umbilical cord cross-section of the HELLP group, endothelial cell degeneration in the vessel wall and basement membrane thickening were observed. In the muscle layer of blood vessels, the following disorders were found: increased collagen fibres in the muscle cell, hyperplasia and separation of muscle fibres as well as edema in the intermediate connective tissue. Immunohistochemical analysis showed that endothelial cells, basal membrane and fibroblast cells in the HELLP group expressed high levels of CD44. Vessel wall and amniotic epithelial basement membrane thickening were observed in the HELLP group. Matrix metalloproteinase 9 (MMP9) was expressed. Fibroblast and smooth muscle cells were fusiform and showed a positive reaction to immunohistochemical staining of α-actin smooth muscle.

Heme oxygenase regulates renal arterial resistance and sodium excretion in cirrhotic rats

Heme oxygenase (HO) catabolizes heme into biliverdin, carbon monoxide (CO), and free iron. CO generated in endothelial and smooth muscle layers of blood vessels modulates vascular tone by inducing relaxation of vascular smooth muscle cells. The aim of this study was to verify the role played by HO in regulating renal arterial resistance and Na(+) excretion in cirrhosis. Twenty control rats and 20 rats with CCl(4)(-) induced cirrhosis, 10 of which were chronically treated with the HO inducer cobalt-protoporphyrin (CoPP), were studied. Pressurized renal interlobar arteries were challenged with increasing doses of phenylephrine (PE) and acetylcholine (ACh). Dose-response curves were evaluated under basal conditions and after inhibition of HO with chromium-mesoporphyrin (CrMP). HO-1 (inducible form) and HO-2 (constitutive form) expression was measured in the main and interlobar renal arteries. Serum and urinary levels of Na(+) and creatinine were also evaluated. In renal interlobar arteries from cirrhotic rats, the response to PE was increased, while that to ACh was blunted. After HO inhibition, the responsiveness to these vasoactive substances was comparable in the two groups. In cirrhotic rats, HO-1 expression was impaired in the main and the interlobar renal arteries. Chronic HO induction normalized the response to the vasoconstrictor, but not to the vasodilator. Cirrhotic rats treated with CoPP showed higher urinary Na(+) concentration and fractional Na(+) excretion, compared to both untreated cirrhotic and control rats. In cirrhotic rats, an impaired HO-1 expression promotes vasoconstriction of renal interlobar arteries. Chronic HO induction normalizes the sensitivity to PE and promotes Na(+) excretion.

The significance of caveolin‐1 expression in parietal epithelial cells of Bowman’s capsule

To analyse the expression of caveolin-1 in normal human kidney and during diseases leading to nephrotic syndrome in children and to compare its pattern with those observed in control samples, both human and animal. The study group was composed of 104 children diagnosed with minimal change disease (MCD), focal segmental glomerulosclerosis (FSGS), lupus glomerulonephritis (LGN) and Schönlein-Henoch glomerulopathy (SH). The research protocol employed direct immunohistochemical assay with the use of mono- and polyclonal antibodies against caveolins. Kidney samples of Wistar rats, wild-type mice and caveolin-1-deficient mice were also analysed. In the control human samples, caveolin-1 was most abundant in the muscle layer of blood vessels and parietal epithelial cells (PECs). Its expression in PECs was significantly lower in children diagnosed with FSGS and LGN than in those with MCD, SH or in controls. In the control animal tissues, except for knock-out mice, caveolin-1 was present in distal convoluted tubules, PECs, endothelial cells and muscle. Caveolae are extremely stable elements of PECs and can be excluded from their cell membrane only in response to the dramatic cell reconstruction observed in FSGS and LGN.

Myoendothelial Electrical Coupling In Arteries And Arterioles And Its Implications For Endothelium‐Derived Hyperpolarizing Factor

1. Considerable progress has been made over the past decade in evaluating the presence of electrical coupling between the endothelial and smooth muscle layers of blood vessels, prompted, in part, by ultrastructural evidence for the presence of myoendothelial junctions. 2. In a variety of vessels ranging in size from conduit arteries down to small arterioles, action potentials have been recorded from endothelial cells that were associated with constriction of the vessels and/or occurred in synchrony with and were indistinguishable from action potentials recorded from the smooth muscle. From these results, it is now firmly established that myoendothelial electrical coupling occurs in at least some blood vessels. 3. Spread of hyperpolarizing current from the endothelium to the smooth muscle is the most likely explanation of the smooth muscle hyperpolarization attributed to endothelium-derived hyperpolarizing factor. Because this hyperpolarization can evoke considerable relaxation of the smooth muscle, myoendothelial electrical coupling has important implications for endothelial regulation of the contractile activity of blood vessels.

Neuropeptide Y Y 1 and neuropeptide Y Y 2 receptors in human cardiovascular tissues

mRNA encoding the human NPY Y 1 and NPY Y 2 receptors were detected in cerebral, meningeal, and coronary arteries using reverse transcriptase–polymerase chain reaction (RT–PCR). In addition, the trigeminal and superior cervical ganglia were positive for both receptors. In some arteries and in SK-N-MC cells only mRNA encoding the NPY Y 1 was detected. Besides the expected NPY Y 1 PCR products, an additional 97 bp longer amplicon originating from an alternative splicing event was found in most tissues studied. Antibodies directed against the NPY Y 1 receptor revealed immunostaining mainly in the smooth muscle layer of blood vessels whereas antibodies against the NPY Y 2 receptor showed immunostaining in nerve cell bodies.

Histochemical localization of rhodanese activity in rat liver and skeletal muscle

A previously described histochemical technique was applied to the localization of rhodanese (thiosulfate sulfurtransferase, EC 2.8.1.1) activity in rat skeletal muscle and liver. The physiological function of rhodanese is controversial, but it and other sulfurtransferases can catalyze the conversion of cyanide to the much less toxic thiocyanate. The volume of distribution of cyanide in human and dog is said to correspond roughly to the blood volume. Because of this and other observations, it was hypothesized that sulfurtransferase activity associated with the vascular endothelium or smooth muscle layers of blood vessels might play a role in cyanide detoxification. However, little enzyme activity as identified histochemically was associated with those sites in comparison with others examined. As expected, high activity was found in the liver and moderately high levels were present in skeletal muscle. In muscles sectioned longitudinally, points of rhodanese staining occurred in linear arrays along the lengths of the muscle fiber corresponding to the location of mitochondria within the fiber. The original technique called for incubation of tissue sections with both thiosulfate and cyanide. When thiosulfate was omitted, staining for rhodanese activity was still clearly identifiable in both liver and muscle sections with cyanide alone. In muscle sections the inclusion of both thiosulfate and cyanide resulted in a preferential staining of type I fibers presumably because of their higher content of mitochondria. Thus, this technique is a potential alternative to the NADH dehydrogenase stain for distinguishing between type I and type II muscle fibers. Incubation of tissue sections with only thiosulfate produced results that did not appear to differ from those obtained when both substrates were omitted. From these observations it may be inferred that the endogenous pool of sulfane-sulfur available to sulfurtransferases is larger than any alleged endogenous pool of cyanide. Although sulfurtransferase activity in muscle appeared to be lower than that in liver, the total body muscle mass is greater than the liver mass. Thus, these results support other evidence that skeletal muscle may make a significant contribution to total cyanide biotransformation in the absence of exogenously added thiosulfate.

Adrenergic innervation of the nasal mucosa in cat. A histological and physiological study.

The adrenergic innervation of the cat nasal mucosa was investigated with fluorescence and electron microscopy. A strong fluorescence attributable to adrenergic nerves was observed on the outer surface of the smooth muscle layer of blood vessels, whereas the fenestrated capillaries showed no evidence of adrenergic innervation. A sparse adrenergic innervation was observed in connection with the mucosal glands. The effects of sympathetic nerve activation and various denervation procedures were evaluated with a local tracer disappearance technique, reflecting the vascular events in the exchange vessels of the maxilloturbinal area. Both functional as well as morphological data pointed to an ipsilateral distribution of the sympathetic nerve fibres from the superior cervical ganglion to the nasal mucosa. The sympathetic postganglionic nerve fibres to the nose travel via the tympanic plexus. After passage through the tympanic plexus, the major sympathetic nerve supply to the maxilloturbinal area travels in the Vi...