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PubMed2005

Altered endothelial function in isolated human myometrial vessels induced by plasma from women with pre-eclampsia is not reproducible in isolated mouse vessels.

In order to facilitate characterization of the circulating factor(s) in pre-eclampsia, the present study aimed to determine whether plasma from women with pre-eclampsia, which induces attenuated endothelial-dependent relaxation in human myometrial arteries, is also capable of inducing altered endothelial function in mouse vessels. Human vessels were isolated from myometrial biopsies taken from women with uncomplicated pregnancies (n = 6). Mesenteric and uterine arteries were isolated from male, female, non-pregnant and pregnant C57B mice (n = 24). Vessels were studied using a wire myograph and incubated with plasma (2%) from women with pre-eclampsia (n = 12) or controls (n = 12). Incubation of myometrial vessels from normal pregnant women with plasma from women with pre-eclampsia reduced endothelial-dependent relaxation. This effect was not reproduced in male or female mouse mesenteric or uterine vessels incubated with plasma from women with pre-eclampsia. In conclusion, there are species-specific differences in the actions of the circulating factor(s) on endothelial-dependent relaxation of human and mouse small arteries.

Adult↗

PubMed1988

Vessel anastomosis using a venous cuff and two sutures: an experimental study in rat femoral and epigastric vessels.

Using rat femoral and epigastric vessels, the efficacy of an autogenous venous cuff and reduction in the number of required sutures were examined. Cut vessels were anastomosed with two sutures using 11-0 nylon, and the anastomotic site was covered with a venous cuff. After two weeks, the patency of the anastomosed vessels was evaluated. Although results in large-caliber femoral veins were poor, the femoral arteries and epigastric vessels demonstrated high patency rates. In microscopic and scanning electron microscopic evaluations, gaps and depressions between sutures were observed, but they were smoothly covered by endothelium. These results suggest the usefulness of the venous cuff in microvascular surgery, especially in anastomosing fine-caliber vessels.

Anastomosis, Surgical↗

PubMed2003

Vulnerability of xylem vessels to cavitation in sugar maple. Scaling from individual vessels to whole branches.

The relation between xylem vessel age and vulnerability to cavitation of sugar maple (Acer saccharum Marsh.) was quantified by measuring the pressure required to force air across bordered pit membranes separating individual xylem vessels. We found that the bordered pit membranes of vessels located in current year xylem could withstand greater applied gas pressures (3.8 MPa) compared with bordered pit membranes in vessels located in older annular rings (2.0 MPa). A longitudinal transect along 6-year-old branches indicated that the pressure required to push gas across bordered pit membranes of current year xylem did not vary with distance from the growing tip. To understand the contribution of age-related changes in vulnerability to the overall resistance to cavitation, we combined data on the pressure thresholds of individual xylem vessels with measurements of the relative flow rate through each annual ring. The annual ring of the current year contributed only 16% of the total flow measured on 10-cm-long segments cut from 6-year-old branches, but it contributed more than 70% of the total flow when measured through 6-year-old branches to the point of leaf attachment. The vulnerability curve calculated using relative flow rates measured on branch segments were similar to vulnerability curves measured on 6-year-old branches (pressure that reduces hydraulic conductance by 50% = 1.6-2.4 MPa), whereas the vulnerability curve calculated using relative flow rates measured on 6-year-old branches were similar to ones measured on the extension growth of the current year (pressure that reduces hydraulic conductance by 50% = 3.8 MPa). These data suggest that, in sugar maple, the xylem of the current year can withstand larger xylem tensions than older wood and dominates water delivery to leaves.

Acer↗

PubMed1999

Sem studies on vessels in ferns. 12. Marattiaceae, with comments on vessel patterns in eusporangiate ferns.

Scanning electron microscopy (SEM) of tracheary elements of roots of five species from four genera of Marattiaceae and of the rhizome of one species revealed vessel elements present in all. The secondary wall framework of perforation plates is the same as that of lateral wall pitting for vessel elements in all species. Thus, no specialization is present in perforation plates of Marattiaceae compared to the simplified morphology of perforation plates of some leptosporangiate ferns (e.g., Dryopteridaceae, Polypodiaceae, and Pteridaceae). The difference between lateral wall pitting and perforation plates in tracheary elements of Marattiaceae cannot be seen by light microscopy (in which pit membranes are transparent), but is evident with SEM. Diversity in structure of perforation plates (especially the alternation of wide and narrow perforations within a plate) and presence of web-like pit membrane remnants are evident. Vessels are widespread in both leptosporangiate and eusporangiate ferns, although specialization in perforation plates (e.g., bars few and more widely spaced in lateral wall pitting of a given vessel element) is to be expected only in ferns of habitats with marked fluctuation in water availability. Vessels of Marattiaceae lack such specializations and are thus are correlated with the mesic habitats characteristic for the family.

Journal Article↗

PubMed1991

[Significance of blood vessel invasion in gastric carcinoma--prediction of liver metastases from the blood vessel invasion in the primary tumors].

This study was conducted to elucidate the factors related with liver metastases, to clarify the significance of blood vessel invasion and then to predict liver metastases from these findings. Patients examined were 102 cases which underwent gastrectomy and were followed-up for more than 5 years or until death at our department. Two new staining methods were applied in this study; Victoria blue + hematoxylin eosin double staining for elastic fiber and Factor VIII related antigen for vascular endothelium. Significant differences in qualitative frequency of blood vessel invasion, the number of lymph node metastases, and the depth of invasion were found in those patients with liver metastases, as compared with 5 year survivors. Quantitative analysis of blood vessel invasion revealed significant importance of blood vessel invasions in the submucosa, in the forms of complete thrombus, wall invasion and partial thrombus, in the diameters of 0.01-0.1 mm and 0.1-1.0 mm. Applying discrimination coefficients of linear discrimination analysis, prediction of liver metastases was possible with 81.8% sensitivity, 85.3% specificity, and 83.6% accuracy. Liver metastases can be predicted from the qualitative and quantitative analyses of blood vessel invasion in the primary tumors by elastic fiber staining.

Gastric Mucosa↗

PubMed1985

Differential endothelial injury caused by vascular clamps and vessel loops. II. Atherosclerotic vessels.

Performance of a vascular anastomosis or repair requires meticulous, gentle technique and a bloodless operative field. Many vascular surgeons rely on commercial "atraumatic" vascular clamps for the latter; however, most experimental evidence incriminates clamps as agents of moderate to severe endothelial and medial injury. Our previous studies in normal canine aortoiliac vessels have demonstrated that silastic rubber vessel loops did not cause injury in that setting; this study examines in vivo atherosclerotic human femoropopliteal artery segments. Ten centimeter segments of perfused femoropopliteal arteries were exposed during performance of above-knee lower extremity amputation for endstage vascular insufficiency. DeBakey, Cooley, Fogarty, and bulldog vascular clamps, and double-looped silastic rubber vessel loops were applied at 3-centimeter intervals for 15 minutes. Each segment was then examined under scanning electron microscopy. All vascular clamps caused endothelial and presumed medial injury; no injury was seen with the vessel loops. Selective and preferential use of silastic rubber vessel loops is thus advocated to minimize iatrogenic complications.

Adult↗

PubMed2001

Prognostic value of absolute versus relative measures of the procedural result after successful coronary stenting: importance of vessel size in predicting long-term freedom from target vessel revascularization.

BACKGROUND: The procedural result is a major determinant of the incidence of 6-month target vessel revascularization (TVR) after successful coronary stenting. However, the prognostic implications of the different measures of the procedural result or procedural end points have not been directly compared. In this study, we sought to assess and compare the impact of achieving different procedural end points on the long-term (2-year) incidence of TVR. METHODS AND RESULTS: We studied 234 patients in whom 1 or 2 stents were successfully deployed and ultrasound imaging performed after angiographic optimization. End points included a visually estimated angiographic residual stenosis <10% and ultrasound stent-to-mean reference lumen area > or = 80%. After 2 years, TVR was required in 48 (20.5%) patients. Qualitative predictors of TVR were vein graft lesions, 3-vessel disease, and baseline TIMI flow grade < 3. Quantitatively, reference diameter by quantitative coronary angiography (QCA), final minimum lumen diameter (MLD) by QCA, and in-stent minimum lumen area (MLA) by ultrasound were predictive of TVR. Stent-to-reference ratios were not significantly predictive of TVR. By multivariable analysis, vein graft location and MLA by ultrasound were the only significant predictors of TVR (relative risk, 2.9 [1.5, 5.4] and 0.72 [0.6, 0.9], respectively). Receiver operator curves for MLD by QCA and MLA by ultrasound were similar in predicting TVR. Neither was significantly superior to reference vessel diameter. CONCLUSIONS: Commonly used angiographic and ultrasound stent-to-reference ratios do not predict the incidence of TVR. Absolute measures of the lumen size (MLA by ultrasound and MLD by QCA) were the most important quantitative predictors of TVR within 2 years. This emphasizes the role of the vessel size as the limiting factor in determining the long-term outcome of coronary stenting.

Blood Vessel Prosthesis Implantation↗

PubMed1984

Relationship between chromaffin cells and blood vessels in the rat adrenal medulla: a transmission electron microscopic study combined with blood vessel reconstructions.

The rat adrenal medulla architecture was examined using a combination of medullary blood vessel reconstructions and transmission electron microscopy. The peripheral radicles of the central vein and the medullary capillaries of the medullary arteries were thus precisely identified in the electron microscopic observations. The observations confirmed that the peripheral segments of the central vein were sinusoidal vessels with an attenuated and fenestrated endothelial wall. No ultrastructural differences were observed between segments lined by epinephrine-storing cells and those lined by norepinephrine-storing cells. The findings suggest that these peripheral segments of the adrenal central vein were sites of cortical hormonal effects on the adrenal medulla. The vessel structure does not support the hypothesis that medullary chromaffin-cell development is controlled by selective distribution of adrenal blood vessels.

Adrenal Medulla↗

PubMed2004

Vessels in benign prostatic hyperplasia contain more binding sites for endostatin than vessels in normal prostate tissue.

OBJECTIVE: The angiogenic phenotype is an effect of a net balance of angiogenic and anti-angiogenic factors. Endostatin is one of a group of recently described matrix-derived inhibitors of tumour angiogenesis that have acquired increasing significance for tumour treatment. Endostatin's anti-angiogenic mechanism and the causes of its heterogenic influence on various tissue types have not yet been defined. METHODS: We investigated the variations in endostatin's binding behaviour to vessels in benign prostatic hyperplasia (BPH) compared to endostatin binding to vessels in normal prostate tissue. Biotinylated endostatin was used and was detected using Extravidin CY3. RESULTS: In BPH 89.12% +/- 10.72% of vessels showed endostatin binding. This was significantly more than observed for vessels in normal prostate tissue (1.66% +/- 1.66%). CONCLUSION: The strongly proliferative tissue of BPH may be a growth-limited cause of significantly more endostatin binding sites. The investigation indicates endostatin as a possible new target for BPH treatment.

Aged↗

PubMedDate not supplied

New vessel analysis tool for morphometric quantification and visualization of vessels in CT and MR imaging data sets.

Image processing algorithms and a prototypical research software tool have been developed for visualization and quantitative analysis of vessels in data sets from computed tomography and magnetic resonance imaging. The software is based on a sequence of processing steps, which are as follows: (a) vessel segmentation based on a region growing algorithm, (b) interactive "premasking" to optionally exclude interfering structures close to the vessels of interest, (c) distance transform-based skeletonization, (d) multiplanar reformation orthogonal to the vessel path, (e) identification of the lumen boundary on the orthogonal cross-section images, and (f) morphometric measurements. The development of the algorithmic components and the application user interface has been carried out in close cooperation with clinical users to achieve a high degree of usability and flexible support of work flow. The software has been successfully applied to the intracranial arteries, carotid arteries, and abdominal and thoracic aorta, as well as the renal, coronary, and peripheral arteries.

Algorithms↗

PubMed1991

Effects of calcitonin gene-related peptide on normal and atheromatous vessels and on resistance vessels in the coronary circulation in humans.

BACKGROUND: Calcitonin gene-related peptide (CGRP) is a potent dilator of normal epicardial coronary vessels in humans, but its effects on myocardial blood flow and atheromatous coronary vessel diameter are unknown. METHODS AND RESULTS: Seven patients were entered for study of the effects of CGRP on coronary blood flow and 13 for the comparison of its effects on normal and atheromatous coronary arteries. In the first seven patients, left anterior descending artery (LAD) diameter at an angiographically normal site, coronary sinus oxygen saturation (CSO2S), systemic blood pressure, and heart rate were measured during intracoronary infusion of increasing concentrations of CGRP (up to 200 ng/ml at 2 ml/min) followed by intracoronary adenosine (0.267 micrograms/ml at 2 ml/min) and finally intracoronary glyceryl trinitrate (GTN) (5 micrograms/ml at 2 ml/min). CGRP dilated the normal segment of the LAD by 22.6 +/- 8% (mean +/- 95% confidence interval), p less than 0.001, with only a small increase in CSO2S from 40.1 +/- 2.7% to 47.3 +/- 2.7%, p less than 0.001. Adenosine, a potent dilator of myocardial resistance vessels, caused no further increase in LAD diameter but caused a rise in CSO2S from 47.3 +/- 2.7% to 76.0 +/- 2.7%, p less than 0.001. GTN caused no further increase in LAD diameter. As heart rate-blood pressure product remained unchanged throughout the study, the increase of CSO2S indicated only a small increase in myocardial blood flow after CGRP infusion. In 13 patients with atheromatous coronary artery disease, the effects of intracoronary CGRP at angiographically normal sites, stenoses, angiographically normal sites immediately adjacent to stenoses, and sites of coronary artery wall irregularity were compared after intracoronary infusion of a single dose of CGRP (200 ng/ml at 2 ml/min) followed by intracoronary GTN (5 micrograms/ml at 2 ml/min). At these four sites, CGRP resulted in dilatation by 17.0 +/- 5.6%, 15.3 +/- 12.1% (NS), 7.6 +/- 5.4% (NS), and 15.9 +/- 7.8%, respectively. There was no significant further dilatation after GTN at any of the four sites. CONCLUSIONS: These data indicate that CGRP has little effect in humans at rest on coronary resistance vessels in nonischemic myocardium but causes marked dilatation of normal arteries and variable dilatation of atheromatous epicardial arteries.

Calcitonin Gene-Related Peptide↗

PubMed2002

Triple vessel stenting for triple vessel coronary disease.

BACKGROUND: Randomized clinical trials have established the feasibility of implanting multiple coronary stents and, in selected patients, have measured survival after multiple stenting to be comparable to coronary artery bypass graft surgery (CABG). However, the proportion of candidates for this therapy is unclear. this prospective study was performed to measure the percentage of patients eligible for elective multiple stenting of triple vessel coronary artery disease and to examine their short- and intermediate-term outcomes. METHODS: Between January 1996 and January 1999, percutaneous coronary interventions (PCI) were performed in 6,810 consecutive patients, of whom 115 (1.7%) had triple vessel coronary artery disease treated with > or =3 stents. The mean age of these patients was 62.9 years (range, 35-85 years), 83% were men and 13 patients (11%) were diabetic. The treatment was performed in a single procedure in 80% of patients and 362 vessels were dilated, including the left anterior descending artery in 85%, the right coronary artery in 84%, the left circumflex in 49%, the left diagonal artery in 27%, the posterior descending artery in 8% and the posterior lateral artery in 4% of patients. RESULTS: A total of 483 stents were implanted, representing an average of 4.2 +/- 1.4 stents per patients (range, 3-10 stents). The total length of stents averaged 66.9 +/- 4.9 mm. In-hospital adverse events included 2 deaths (1.7%), 2 emergency CABG (1.7%) and 5 myocardial infarctions (4.3%). The mean hospitalization duration was 2.7 +/- 2.2 days. During a follow-up ranging between 1 and 36 months (mean, 16.7 months), 2 patients died (1.7%), 2 patients underwent CABG (1.7%) and 22 patients (19.1%) underwent further coronary artery dilatations. The 3-year event-free survival was 71.3%. In univariate analysis, patients who underwent additional target vessel revascularization were younger and were more likely to have stented segments > 80 mm in the index procedure. No other clinical, angiographic or procedural characteristic was predictive of adverse events. CONCLUSIONS: In this consecutive series of patients undergoing elective PCI, candidates for stenting of > or =3 arteries were few. Most eligible patients underwent uncomplicated and immediately successful procedures. The long-term outcome was comparable to controlled studies of CABG, except for a higher rate of repeat revascularization procedures due to restenosis.

Age Factors↗

PubMed1990

[Studies of age-related changes in intracerebral small vessels of rat--do all cerebral blood vessels get aging concurrently?].

Age-related changes of intracerebral small blood vessels were studied with light and electron microscopes. In the first step of this investigation (Experiment 1), Wistar rats of 4-month-old were employed to determine the appropriate concentration of administrated HRP (horseradish peroxidase) for surveying the uptake capacity of HRP. Each rat was injected HRP intravenously under light anesthesia with ether. After 30 minutes, rat brains were excised and prepared for stretch specimen (Mato et al, 1979). Light microscopically, corresponding with decrease of the concentration of injected HRP, the reaction products of HRP in the cytoplasm of fluorescent granular perithelial (FGP) cells reduced linearly and the injection of 5 mg HRP revealed only FGP cells in the parietotemporal region of cerebral cortex. Referring to the results mentioned above, 10 mg of HRP was decided to be applicable dose for the following study. In the next experiment (Experiment 2), Wistar rats of 4-month-old, 1.7-year-old and 2.4-year-old were used for the study on the relation between morphological alteration of vascular cells and changes of uptake capacity of FGP cells in aging. At 30 minutes after the injection of 10 mg, rats were perfused and fixed with 2.5% glutaraldehyde and 2% paraformaldehyde under light anesthesia. Then, rat brains were removed and divided coronally into three parts. After slicing with Vibratome, number and distribution of FGP cells were studied under light microscope. The other specimens were dehydrated and embedded in Epon 812. The ultrastructure of vascular cells (endothelial and smooth muscle cells) and FGP cells at each age was examined with JEM 2000 EX electron microscope. Supplementary, ultrastructure of middle cerebral and retinal arteries of 2.4-year-old rats was also studied for comparison with that of the intracerebral (cortical)small vessels. The findings obtained from Experiment 2 could be summarized as follows; 1. Light microscopically, in 4-month-old and 1.7-year-old rats, FGP cells including positive granules of HRP were often recognizable along small blood vessels of cerebrum, especially in cerebral cortices. In 2.4-year-old rats, the numbers of FGP cells with positive granules of HRP decreased significantly (p less than 0.01). It was confirmed that the uptake capacity of FGP cells reduced with aging. But, exceptionally, regardless from aging of animals, FGP cells belonging to a few special vessels in the parietotemporal area of cerebral cortices included many and intense reaction products. 2. Electronmicroscopically, the vascular cells changed in appearance and contents with aging.(ABSTRACT TRUNCATED AT 400 WORDS)

Aging↗

PubMed1995

A new photopolymerizable blood vessel glue that seals human vessel anastomoses without augmenting thrombogenicity.

A new nonbiologic photopolymerizable glue, polyethyleneglycol 400 diacrylate, was studied with respect to its mechanical and biochemical interaction with human blood vessels. Using the human placental artery model, we tested the ability of polyethyleneglycol 400 diacrylate to prevent leakage of blood at the site of vascular anastomoses, which are made porous by the presence of tissue gaps and suture puncture sites. Fibrin glue is known to augment local vessel thrombogenicity through the presence of the coagulation enzyme thrombin. We tested the effect of externally applied polyethyleneglycol 400 diacrylate (which does not contain thrombin) on luminal thrombin activity and platelet deposition from flowing human blood. At a shear rate of 312 per second and a transmural pressure of 80 cm H2O, the leakage rate of saline from human placental artery anastomoses was 1.0 +/- 1.2 ml/min (n = 8). When the same anastomoses were then glued, 7 of 8 of the anastomoses leaked less than 0.05 ml/min (p < 0.05). Platelet deposition to human vessels was not influenced by the external application of polyethyleneglycol 400 diacrylate either on intact vessels (no polyethyleneglycol 400 diacrylate, 0.51 +/- 0.28 x 10(6) platelets/cm2; with polyethyleneglycol 400 diacrylate, 0.47 +/- 0.26 x 10(6) platelets/cm2; n = 7) or at anastomoses (no polyethyleneglycol 400 diacrylate, 0.69 +/- 0.36 x 10(6) platelets/cm2; with polyethyleneglycol 400 diacrylate, 0.53 +/- 0.33 x 10(6) platelets/cm2; n = 8), p > 0.05.(ABSTRACT TRUNCATED AT 250 WORDS)

Anastomosis, Surgical↗

PubMed1987

Tumours acquire their vasculature by vessel incorporation, not vessel ingrowth.

This study was designed to investigate the early development of tumour circulation using a transplantable mouse mammary adenocarcinoma. Tumour cells (10(6] were injected subcutaneously into the flank and groups of treated mice were killed at 24 h intervals up to 12 days; the tumours and surrounding tissues being processed by standard histological methods. Sections of tumour were sub-divided into neoplastic tissue, vessels and connective tissue using computer-assisted morphometric techniques: the host tissue around the tumour was similarly quantified for vessels and connective tissue. With increasing tumour size, the proportion of vessels within tumours rapidly increased to reach a plateau of approximately 1.5 per cent of tumour volume, a 400 per cent increase on the vascular density of normal subcutaneous tissue. Within tumours, vascular density was always higher at the periphery than the centre. The most pronounced increase in vascular density affected the host tissue around the tumour. It is not clear why vascular development is most prominent outwith the tumour when postulated angiogenic factors, such as tumour angiogenesis factor, are presumably released within. Our results imply, however, that tumours acquire their vasculature by infiltration into, and expansion between, a network of newly formed vessels in the surrounding connective tissue.

Adenocarcinoma↗

PubMed1994

Algorithm effects on computerized vessel analysis from digitized cine film and a new method of generating the centerline of a vessel.

This study concerns methods of accurately measuring vessel diameters using coronary cineangiograms. Various edge detection filters are compared and a new method for determining the centerline of a vessel is developed. Vessel phantoms of different sizes are used to evaluate the precision and accuracy of an entropy filter, a combined first and second derivative filter, a Laplace-Gaussian filter, a first derivative filter and a second derivative filter. The entropy filter is found to yield the most reliable, precise and accurate data. For use in a clinical case with an irregular arterial wall, a new method of determining the centerline is delineated in which the centerline of a vessel (which we define as a set of points having equal distance to each of any two opposite edge lines) is calculated with images called distance maps. We find that this method of detecting the centerline provides an acceptable assessment of the centerline on visual evaluation.

Cineangiography↗

PubMed1985

Functional differences in blood vessels determined from studies with calcium-channel blockers. Functional changes in forearm resistance vessels of men with primary hypertension.

Vascular smooth muscle is activated through 2 major systems. One, which can be inhibited by calcium-entry blocking agents, involves the influx of calcium through potential-sensitive channels. The other, which can be inhibited by sodium nitroprusside, involves the entry of calcium through agonist-controlled channels and probably its mobilization from within the cell as well. Human veins, muscular arteries and resistance vessels show differing patterns of response to agents that selectively inhibit the 2 activation systems. The responses indicate that physiologic contractions of cutaneous veins and muscular arteries depend on the agonist-controlled system; contractions of veins induced by high concentrations of potassium depend on the potential-sensitive system as, probably, does local spasm in arteries. The tone of resistance vessels depends on a balance between the potential-sensitive and agonist-controlled systems. The forearm resistance vessels of men with primary hypertension respond to verapamil with larger-than-normal dilatation compared with that induced by nitroprusside. This is interpreted as showing an increased contribution to resistance vessel tone from the potential-sensitive system. This functional abnormality does not depend on the inhibition of sodium pump activity that is known to occur in hypertension, because it cannot be reproduced by local infusion of ouabain. It probably results from a primary disorder of calcium handling by the cell membrane.

Calcium Channel Blockers↗

PubMed1991

Crystalloid inclusion bodies of the endothelial cells in human fetal skin blood vessels and human umbilical cord vessels: a possible relationship to Weibel-Palade bodies?

Crystalloid inclusion bodies (CIB) of the endothelial cells (EC) were investigated in blood vessels of human fetal skin and the umbilical cord by electron- and immunoelectron microscopy. They were found in up to 15% of the investigated EC in various types of vessels. Their sizes ranged from 0.2 microns to 0.6 microns in the largest diameter. Most frequently we observed a laminated pattern of the crystalloid structure with a regular periodicity of dark and light bands. Additionally a honeycomblike pattern was also seen. Measurement of the CIB laminated structure revealed similar dimensions to Weibel-Palade bodies (WPB). In EC of all vessel types we found numerous WPB differing in electron density, shape and size from those of WPB found in adult blood vessels. WPB were found much less frequently in EC with CIB, suggesting that CIB is a precursor of WPB. After incubation with monoclonal antibody against von Willebrand factor (vWf) both WPB and large organelles were labeled. Because of their shape and size the labeled large organelles seemed to represent inadequately preserved CIB. After incubation with anti-lysozyme only the large organelles were labeled. A possible relationship of CIB to WPB is thus suggested. The presence of lysosomal enzymes such as lysozyme suggest that CIB are lysosomal organelle and participate in the uptake of vWf. The crystalloid pattern of CIB may represent an accumulation of a highly condensed form of vWf.

Endothelium, Vascular↗