A high accumulation of minerals in human internal jugular vein

To elucidate age-related changes of mineral contents in human veins, the relative contents (RCs) of elements in the human internal jugular veins, superior and inferior venae cavae, and femoral veins from 27 subjects ranging from 40 to 98 yr old were analyzed by inductively coupled plasma atomic emission spectrometry. The average RCs of calcium in the 27 specimens were the highest in the internal jugular vein, followed in descending order by the superior vena cava, femoral vein, and inferior vena cava. The RCs of calcium and phosphorus in the internal jugular veins started to increase after the age of 50 yr, became the highest in subjects in their 60s and thereafter decreased gradually. It is noted that such accumulations of minerals, similar to the internal jugular vein, were also found in the veins, such as the superior and inferior venae cavae, and femoral vein. Accumulation of minerals in the veins is different from that of arteries, which increase progressively by aging, but do not decrease.     

Intravascular pressure profiles in elephant seals: hypotheses on the caval sphincter, extradural vein and venous return to the heart

In order to evaluate hemodynamics in the complex vascular system of phocid seals, intravascular pressure profiles were measured during periods of rest-associated apnea in young elephant seals (Mirounga angustirostris). There were no significant differences between apneic and eupneic mean arterial pressures. During apnea, venous pressure profiles (pulmonary artery, thoracic portion of the vena cava (thoracic vena cava), extradural vein, and hepatic sinus) demonstrated only minor, transient fluctuations. During eupnea, all venous pressure profiles were dominated by respiratory fluctuations. During inspiration, pressures in the thoracic vena cava and extradural vein decreased -9 to -21 mm Hg, and -9 to -17 mm Hg, respectively. In contrast, hepatic sinus pressure increased 2-6 mm Hg during inspiration. Nearly constant hepatic sinus and intrathoracic vascular pressure profiles during the breath-hold period are consistent with incomplete constriction of the caval sphincter during these rest-associated apneas. During eupnea, negative inspiratory intravascular pressures in the chest ("the respiratory pump") should augment venous return via both the venae cavae and the extradural vein. It is hypothesized that, in addition to the venae cavae, the prominent para-caval venous system of phocid seals (i.e., the extradural vein) is necessary to allow adequate venous return for maintenance of high cardiac outputs and blood pressure during eupnea.     

Arterial versus venous endothelial cells

Vascular endothelial cells (ECs) form the inner lining of all blood vessels from the largest artery and veins, viz., the aorta and venae cavae, respectively, to the capillaries that connect the arterial and venous systems. Because these two major conducting systems of the cardiovasculature differ functionally, it is not surprising that the physical makeup of arteries and veins, including the ECs that line their lumina, are also distinct. Although few would argue that the local environment contributes to the differences between arteries and veins, recent evidence has shown that the specification of arterial and venous identity is largely genetically determined. The authors are supported by NIH EY05318 and EY015435 (P.A.D.). Dr. dela Paz is supported by NRSA Institutional Research Training Grant T32 HL076115. Dr. D’Amore is a Research to Prevent Blindness Senior Scientific Investigator.     

Age and changes in the nerve supply of the superior and inferior venae cavae in man

The superior and inferior venae cavae have been studied in 51 human being at various age, beginning from newborns using histochemical methods. After birth concentration of neural plexuses in the venae cavae increases up to the period of puberty, and then after 40years of age, certain rarefication of adrenergic and then cholinergic neural plexuses is noted. Choline- and adrenergic innervation is revealed in myocardial fibers penetrating the walls of the superior and inferior venae cavae.     

A possible balance of phosphorus accumulations among bone, cartilage, artery, and vein in single human individuals

To elucidate relationships between the decrease of mineral contents in human bones and the accumulation of minerals in the other human tissues, the contents of phosphorus in human bones, arteries, veins, and cartilages in 27 subjects (17 men and 10 women) were analyzed by inductively coupled plasma-atomic emission spectrometry. These were resected from subjects who died in the age range 40–98 yr. Calcanei were chosen for analysis of mineral contents in contrast to arteries such as the femoral, popliteal, and common carotid arteries, veins such as superior and inferior venae cavae, internal jugular, and femoral veins, and pubic symphyses. It was found that the content of phosphorus in calcanei was in agreement with that in both the pubic symphysis and the arteries such as femoral, popliteal, and common carotid arteries, but it was not in agreement with that in the veins such as superior and inferior venae cavae, internal jugular, and femoral veins. This suggests that phosphorus released from bones is accompanied by accumulations of phosphorus in the artery and cartilage.     

Venous stasis and state of the microcirculatory bed in the synovial membranes]

Microcirculatory bed of the synovial membranes was investigated in experiments on dogs during venous stasis. Ligation of the femoral vein and circulatory disturbances led to the alteration of the microcirculatory bed of the synovial membranes, to the overfilling of the venules. Capillary walls became thinner and there developed swellings and protrusions. The extent of the vascular wall changes depended on the calibre of the vessels. One month after the ligation of the vein congestive phenomena in the tissue of the joint capsule proved to decline. This indicated development of collateral venous circulation.     

Presence of atrial natriuretic polypeptide in the pulmonary vein and vena cava

Striated muscle cells and storage granules observed in the atria were found in main branches of the pulmonary veins and superior and inferior venae cavae of the rat, pig, and ox. The presence of atrial natriuretic polypeptide (ANP) in these veins was examined by reverse-phase high-performance liquid chromatography coupled with a radioimmunoassay for ANP. The veins contained 0.6 to 8.0 ng ANP/mg wet tissue with the major molecular form being gamma-ANP. ANP was detected in the peripheral lung tissue in a small quantity, but was not detected in the pulmonary artery. The identification of gamma-ANP and storage granules stained with an anti-ANP antiserum in the pulmonary vein and vena cava suggest that the veins may participate in regulating volume status, blood pressure, and cardiovascular homeostasis through the release of ANP.     

Anatomy of the crocodilian spinal vein

The crocodilian spinal vein is remarkably robust yet historically overlooked. Using corrosion casting, we describe the anatomy of this vessel and its connections with the caval and hepatic venous systems in representatives from four crocodilian genera. The spinal vein arises from an enlarged occipital sinus over the medulla and extends the entire length of the vertebral column. Unlike in squamate reptiles, the spinal vein is single (nonplexiform), voluminous, and situated dorsal to the spinal cord, and plexi lateral to the cord span between emerging intercostal veins. The connections with the other venous systems are otherwise similar to those in other tetrapods. The overall anatomy of this vessel and its abundant connections with the other venous systems indicate it likely plays a primary role in returning blood to the heart from all parts of the body. Preliminary studies of function suggest that this vessel could also play an adaptive role during basking and diving.     

Effect of acute lymphatic obstruction on fluid accumulation in the chest in dogs.

The effect of acute obstruction to lymphatic drainage on fluid accumulation in the lungs, pleura, and pericardium was assessed in the intact dog. Catheters were positioned in the venae cavase, right atrium (RA), left atrium (LA), age on fluid accumulation in the lungs, pleura, and pericardium was assessed in the intact dog. Catheters were positioned in the venae cavae, right atrium (RA), left atrium (LA), and aorta (Ao) of nine anesthetized, spontaneouly breathing dogs, and hydrostic and colloid osmotic pressures were continuously monitored. Lymphatic obstruction was achieved by raising systemic venous pressure to either 10 mmHg or 25 mmHg by a combination of fluid infusion and inflation of balloon catheters in the venae cavae for 2 h. The same constant net intravascular filtration pressure was maintained in both groups by appropriate use of saline or colloid-containing fluids. Pleural and pericardial fluids were measured postmortem and lung water content was determined by weighing before and after drying. Failure to detect greater fluid accumulation at the higher obstructing pressure (25 mmHg) than at the lower obstructing pressure (10 mmHg) suggests that over the range of obstructing pressures used there is no acute change in the magnitude of lymphatic drainage in the chest.     

Immunocytochemical localization of atrial natriuretic peptide in the venae cavae and the pulmonary veins of the rat

Summary In the present investigation atrial natriuretic peptide (ANP) was localized in striated myocytes of the venae cavae and the pulmonary veins in the rat by the use of immunohistochemical and immunocytochemical staining techniques. ANP was stored in granules which appeared to be morphologically similar to the atrial specific granules (ASG) of the atria. In general, the amount of ASG in the great thoracic veins was less than observed in the atria, and the specific granules appeared to be more evenly distributed throughout the sarcoplasm. However, the presence of ANP-containing specific granules in the venae cavae and the pulmonary veins may suggest participation of these veins in the production and secretion of the hormone.     

A possible balance of magnesium accumulations among bone, cartilage, artery, and vein in single human individuals

It is known that a large quantity of magnesium contains bones, and the magnesium contents in spongy bones decrease gradually with advancing age. To elucidate the relationships between a decrease of mineral contents in human bones and an accumulation of minerals in the other human tissues, the content of magnesium was analyzed by inductively coupled plasma-atomic emission spectrometry among human bones, arteries, veins, and cartilages in 27 subjects (17 men and 10 women). These were resected from the subjects who died in the age range 40–98 yr. Calcanei were chosen for analysis of magnesium contents in contrast with femoral, popliteal, and common carotid arteries, internal jugular and femoral veins, superior and inferior venae cavae, and pubic symphyses. The magnesium contents in the calcanei decreased gradually with aging, whereas they increased progressively in the arteries, veins, and pubic symphyses with aging. It was found that as the magnesium contents decreased in the calcanei, they increased in the arteries, such as the femoral, popliteal, and common carotid arteries, whereas they decreased inversely in the veins, such as the internal jugular and femoral veins and superior and inferior venae cavae. Furthermore, as the magnesium contents decreased in the calcanei, they hardly changed in the pubic symphyses. These suggest that magnesium released from bones is accompanied by accumulation of magnesium in the arteries.     

Venous drainage in the reverse forearm flap

Venograms were performed in three cases of reverse forearm flap. The "crossover pattern" of the communicating branches between the two venae comitantes and the "bypass pattern" of the collateral branches of each vein have been demonstrated. These factors may explain the reverse drainage of venous blood, even though the valves of the vein are intact. Notably, the cephalic vein also shows a good communication with the deep venous system. Thus it can contribute another route for venous drainage in this flap.     

Effects of orally administered OP-1206 alpha-CD with loxoprofen-Na on walking dysfunction in the rat neuropathic intermittent claudication model

An orally active prostaglandin E1 analogue, OP-1206 alpha-CD improves walking dysfunction in the rat spinal stenosis model. Loxoprofen-Na, a non-steroidal anti-inflammatory drug, is used to relieve chronic pain in patients with lumbar spinal canal stenosis. To determine whether the OP-1206 alpha-CD in combination with loxoprofen-Na could induce a greater therapeutical effect on walking dysfunction and spinal cord blood flow (SCBF) than OP-1206 alpha-CD treatment alone after chronic spinal stenosis in the rat. Spinal stenosis was induced by placing two pieces of silicon rubber strips in the lumbar (L4 and L6) epidural space of rats. After surgery, walking function was measured using a treadmill apparatus and SCBF was measured using a laser-Doppler flow meter. Drugs were administered orally twice a day for 11 days from the day 3 post-surgery. OP-1206 alpha-CD elicited a significant improvement of walking dysfunction on days 7 and 14 post-surgery and significantly increased spinal cord blood flow on day 15, whereas walking dysfunction and SCBF of rats treated with loxoprofen-Na alone remained unchanged. Combined treatment of OP-1206 alpha-CD with loxoprofen-Na did not provide additive therapeutical effect. These results suggest that a significant improvement seen after OP-1206 alpha-CD treatment is primarily mediated by improvement of the local spinal cord blood flow. This effect is not ameliorated or potentiated by a combined treatment with loxoprofen-Na.     

Correlations of calcium accumulations in arteries, veins, cartilages, ligaments, and bones in single humans

To show the relationships of calcium accumulation in the thoracic aorta to the other tissues, calcium contents were determined with a microwave-induced plasma-atomic emission spectrometer on arteries, veins, cartilages, ligaments, and bones. These tissues were resected from 18 individuals, consisting of 11 men and 7 women who died in the age range 59–91 yr. As thoracic and abdominal aortas are routinely used for radiographic examination of arterial calcification, they appear to be standard tissues of the calcium accumulation. The calcium accumulations were determined in the femoral artery, the superior and inferior venae cavae, the internal jugular vein, cartilages of the articular disk of the temporomandibular joint and the intervertebral disk, both the ligaments of the anterior cruciate ligament and the ligamentum capitis femoris, and the calcaneus, in contrast with the thoracic aorta. As calcium increased in the thoracic aorta, it increased in the femoral artery, the articular disk of the temporomandibular joint, the intervertebral disk, both ligaments of the anterior cruciate ligament, and the ligamentum capitis femoris, but it did not increase in veins, such as the superior and inferior venae cavae and the internal jugular vein. In contrast, it decreased in the calcaneus.     

Ependyma and meninges of the spinal cord of the mouse

Summary In addition to ependymal epithelial cells, numerous tanycytes are found along the entire central canal of the mouse. These tanycytes are arranged in clusters in the cervical, thoracic and lumbar segments of the spinal cord. In the conus medullaris, tanycytes separate and ensheath bundles of myelinated and unmyelinated axons; their processes take part in the formation of the stratum marginale gliae. In the caudal part of the spinal cord, the ventral wall of the central canal is thin and some areas are reduced to a single-cell thickness. In this region, ependymal cells participate directly in the formation of the stratum marginale gliae.The meninges consist of the intima piae, the pia mater, the arachnoid, a subdural neurothelium and the dura mater. The subarachnoid space appears occluded and opens only around the spinal roots. In the vicinity of the spinal ganglia, the dura mater, the subdural neurothelium and the arachnoid form a cellular reticulum.     

Anomalous caudal vena cava passing through the vertebral canal in a calf

A 15-day-old female Holstein-Friesian calf with an anomalous caudal vena cava was examined macroscopically, roentgenologically, and histologically. The calf, weighing 43 kg, had severe scoliosis. A common renal vein merged into a single venous trunk formed by the union of the left and right common iliac veins. The trunk entered the vertebral canal through the left intervertebral foramen formed by the last (13th) thoracic and the first lumbar vertebrae. The trunk continued along the ventral side of the narrowing spinal cord inside the canal, and then ran out the left intervertebral foramen formed by the 8th and 9th thoracic vertebrae and emptied via the right azygos vein into the cranial vena cava. In contrast, the hepatic vein passed through the foramen vena cava independently of the trunk and entered the right atrium directly. The pathogenesis of the present anomaly may be explained as follows: The right subcardinal vein, failing to make connection with the liver, shunted directly into the right azygos vein derived from the right supracardinal vein. The body axis began to curve before ossification of the vertebrae occurred. Consequently, the developing right supracardinal vein, located close to the spinal cord, is thought to have become enclosed in the vertebrae with the spinal cord during the early fetal stages.     

Distribution of atrial natriuretic polypeptide (ANP)-containing cells in the rat heart and pulmonary vein Immunohistochemical study and radioimmunoassay

Summary The distribution of atrial natriuretic polypeptide (ANP) was immunohistochemically surveyed in the rat heart and lung using an antiserum raised against -human ANP. The ANP-immunoreactive cells were seen to be distributed in the atrial walls and proximal portions of the pulmonary vein and venae cavae, but were absent from the aorta, pulmonary arteries, trachea, bronchus, and alveolar cells. The immunoreactive cells were present in a narrow region just beneath the endothelium of the pulmonary vein and vena cavae, and, ultrastructurally and immunocytochemically, were seen to be striated muscle cells with ANP-containing specific granules similar to those seen in atrial cardiocytes. A radioimmunoassay for ANP revealed a content of 604±51 pg/mg wet weight in the pulmonary vein, and 3343±1620 pg/mg wet weight in the venae cavae. In addition to the atrial wall, the proximal portion of both the pulmonary vein and venae cavae are suggested to be constituents of an ANP-producing organ.     

Distribution of intraventricularly injected horseradish peroxidase in cerebrospinal fluid compartments of the rat spinal cord

Summary The circulation of the cerebrospinal fluid along the central canal and its access to the parenchyma of the spinal cord of the rat have been analyzed by injection of horseradish peroxidase (HRP) into the lateral ventricle. Peroxidase was found throughout the central canal 13 min after injection, suggesting a rapid circulation of cerebrospinal fluid along the central canal of the rat spinal cord. It was cleared from the central canal within 2 h, in contrast with the situation in the brain tissue, where it remained in the periventricular areas for 4 h. In the central canal, HRP bound to Reissner's fiber and the luminal surface of the ependymal cells; it penetrated through the intercellular space of the ependymal lining, reached the subependymal neuropil, the basement membrane of local capillaries, and appeared in the lumen of endothelial pinocytotic vesicles. Furthermore, it accumulated in the labyrinths of the basement membrane contacting the basolateral aspect of the ependymal cells. In ependymocytes, HRP was found in single pinocytotic vesicles. The blood vessels supplying the spinal cord were classified into two types. Type-A vessels penetrated the spinal cord laterally and dorsally and displayed the tracer along their external wall as far as the gray matter. Type-B vessels intruded into the spinal cord from the medial ventral sulcus and occupied the anterior commissure of the gray matter, approaching the central canal. They represented the only vessels marked by HRP along their course through the gray matter. HRP spread from the wall of type-B vessels, labeling the labyrinths, the intercellular space of the ependymal lining, and the lumen of the central canal. This suggests a communication between the central canal and the outer cerebrospinal fluid space, at the level of the medial ventral sulcus, via the intercellular spaces, the perivascular basement membrane and its labyrinthine extensions.     

Ultrastructural changes in the microcirculatory bed and filtration-reabsorption barrier of the kidney during temporary ischemia after unilateral nephrectomy

Ultrastructure of cellular elements of the microcirculatory bed and filtration-reabsorption barrier has been studied in 150 mature white rats, in which vascular fasciculus of the left kidney has been compressed for 30 min, 1-2 h with a subsequent restoration of the blood stream in the organ undergone ischemia on the 3rd, 7th, 14th, 30th, 60th, 180th, 360th days under conditions of the preliminarily right kidney nephrectomy. On the 3rd day after ischemia of the remained kidney for 30 min, structural components of the walls of the glomerular arterioles and those of the filtration-reabsorption barrier undergo certain ultrastructural changes, that with time elapsed (7, 14 days) gradually pass away, and amount of cells with hypertrophic processes increases. Ischemia for 1 h in the remained kidney with subsequent restoration of the blood stream on the 3rd, 7th days produces in the structures mentioned more pronounced destructive changes. During subsequent compensatory hypertrophy (the 30th, 60th days) of the remained kidney after its ischemia, in the microcirculatory bed elements and in the convoluted canal epitheliocytes intracellular regenerative and hyperplastic processes develop. However, ischemia for 2 h in the remained kidney produces severe destructive-necrotic phenomena in ultrastructure of the microcirculatory bed and of the filtration-reabsorption barrier.