Extravascular Protein Research Articles

Extravascular protein measurements in vivo and in situ by ultramicrospectrophotometry

By means of ultramicrospectrophotometry the amount of extravascular plasma protein in the perivasal connective tissue was determined in vivo and in situ, using as an object the mesenterial plate of an everted intestinal loop of the rat. As with the circulating blood plasma, the protein content in the perivascular space lies in the range of 7–52%. We calculated the mean protein amount in 1 g of interstitial tissue as 3.4 mg. Outside the wall of venules the protein content was significantly higher than around capillaries or arterioles. Further from the vascular wall, the protein content decreases in the interstitial tissue. These concentration gradients were significantly higher around the venules than around the arterioles. The extravascular protein in steady state conditions of permeability is, therefore, not equally distributed within the interstitial space.

High capillary permeability in fishes

1. 1. Protein concentration in extravascular fluid is almost equal to plasma protein concentration in cod ( Gadus morhua) and flounder ( Pleuronectes platessa). 2. 2. The high extravascular protein concentration in fishes suggests a high capillary permeability to proteins, and thus, the effective colloid osmotic pressure across the capillary membrane is much less than that predicted by plasma protein concentration alone. 3. 3. Since protein permeability is high through their capillary membrane, polar fishes can tolerate substantial changes in plasma protein concentration without corresponding adjustments in blood hydrostatic pressure. 4. 4. Plasma protein retention in blood correlates directly with blood hydrostatic pressure on a comparative ascending scale in vertebrates: fishes, amphibians, reptiles, mammals and birds.

The effect of antidiuretic hormone on the permeability of the vessels of the renal medulla of the rat during water diuresis.

Diuresis was induced in 40 Wistar rats by the intraperitoneal injection of water. Of these animals, 20 were given, during the diuresis, a subcutaneous injection of 50 mU of Pitressin Tannate in oil. The extravascular protein in the renal medulla was estimated by injecting Evans Blue as a protein label, washing out the medullary vessels with saline and estimating the Evans Blue remaining in the tissues by a spectrophotometric method. It was found that after Evans Blue had been allowed to circulate for 2 min, almost twice as much extravascular dye was found in the diuretic rats as in those which had been treated with ADH. It is suggested that the extravascular protein hinders the removal of interstitial water by the vasa recta during diuresis, while during antidiuresis the oncotic pressure within the vessels causes removal of water from the medulla by means of the ascending vasa recta.

Drug displacement from protein binding: source of the sulphadoxine liberated by phenylbutazone.

1. A quantitative study has been made of the redistribution of sulphadoxine produced by phenylbutazone in live sheep.2. From calculations based on plasma measurements, 73% of the sulphadoxine in the body can be accounted for as the sum of the plasma-bound, extracellular-free and intracellular-free drug in the whole animal. This sum is termed the accountable sulphadoxine.3. After the injection of phenylbutazone there was a large shift of sulphadoxine from the plasma-bound form into the free form. The gain in free drug significantly exceeded the loss of bound sulphadoxine from the intravascular compartment, but the discrepancy could easily be explained by displacement of some bound sulphadoxine from extravascular plasma protein.4. Phenylbutazone did not displace sulphadoxine from sheep erythrocytes in vitro, nor from homogenates of liver, kidney or skeletal muscle.5. Although the existence of other susceptible binding sites cannot be entirely excluded, this evidence strongly suggests that all the sulphadoxine liberated by phenylbutazone comes from binding sites on plasma protein.

Ocular vascular permeability. Effect of systemic administration of bacterial endotoxin.

Intravenously administered bacterial endotoxin induces an acute marked alteration in ocular vascular permeability in the rabbit. This effect was measured using a dual radioisotope technique employing red blood cells labeled with Ferrie chloride Fe 59 and human serum albumin labeled with iodine 131. Sites of vascular leakage were identified by a topographic analysis utilizing carbon particles systemically. Ocular blood volume was unchanged until 12 hours after endotoxin when a 50% rise was noted. Extravascular protein (extravascular albumin space—EVAS) was seven times greater than in the normal rabbit at two to four hours, twice as great at 12 hours, and was returning to normal at 24 hours. Leakage was primarily in ciliary processes, and by 12 hours, these were markedly edematous. The HSA 131 I content in the aqueous was only a partial indication of the extent of the vascular permeability change.

Renal complications of cardiopulmonary bypass.

Renal failure following cardiopulmonary bypass is an infrequent complication. Many patients who succumb in the early postoperative period, however, show evidence of multiple organ failure. As a result, the actual incidence of renal failure is difficult to assess. It has been reported as ranging between 2 and 10 per cent of cases.1-4 Once renal failure is established following cardiopulmonary bypass, the mortality is high.4 Following intracardiac surgery, hyperkalemia appears earlier and progresses rapidly in comparison with renal failure from other causes.5 Renal compensatory mechanisms required for acid-base balance are depressed and a series of interrelated cardio-renal-respiratory abnormalities is initiated which can terminate in death.#{176} In general, renal failure is defined by the onset of the inability of the kidneys to vary urine content and volume appropriately in response to homeostatic needs. Following bypass, these needs are maximal. In any setting, renal failure is classified into two major types: (1) functional, which is precipitated by extra-renal factors and is immediately reversible by arresting or correcting the renal action of these factors, and (2) organic, which is not immediately reversible by arresting or correcting the action of extra-renal precipitating factors. Functional renal failure accompanies nearly every cardiopulmonary bypass procedure and, if prolonged, can lead to organic failure with tubulorrhexis associated with bloodless capillaries, extravascular protein, heme pigment, and casts within nephron

Capillary Permeability to and Extravascular Dynamics of Myoglobin, Albumin and Gammaglobulin in the Uvea

AbstractThe dynamics of myoglobin, albumin and gammaglobulin in the tissue fluids of the rabbit eye were studied in two‐isotope experiments to elucidate the mechanisms for transcapillary movement of protein and protein drainage from the eye, the nature of the blood‐aqueous barrier and the way in which extravascular protein may influence the formation of aqueous humor.The permeability of the blood vessels of the choroid and the ciliary processes to myoglobin was 10 to 15 times higher than that to albumin which was about twice that to gammaglobulin.In the tissue fluid of the ciliary processes the turnover rate constant for myoglobin was 25 per cent/min, for albumin it was 3.9 per cent/min and for gammaglobulin 1.6 per cent/min.The extravascular albumin spaces in the ciliary processes and the choroid were 158 μl/g and 165 μ/g respectively.The extravascular albumin spaces were 68 and 57 per cent of the myoglobin spaces in the ciliary processes and the choroid, respectively.The extravascular gammaglobulin spaces were 87, 98 and 117 per cent of the extravascular albumin spaces in the choroid, the ciliary processes and the rest of the anterior uvea, respectively.The methods employed will give new information about the dynamics of the tissue fluids also in tissues with lymph vessels.

Effects of Intensive Plasmapheresis on Normal Blood Donors

Abstract Plasmapheresis was performed in normal blood donors using simple plastic equipment. Removal of plasma in amounts up to 1.0 liter at a single venipuncture proved feasible and produced no major changes in the donor’s blood counts and serum protein levels. Chronic plasmapheresis for periods up to 23 weeks with maximal rates not exceeding 1.5 liters of plasma withdrawn per week, produced no changes in formed elements and only minor changes in serum protein levels. Five donors were subjected to acute plasmapheresis with removal of 5 liters of plasma in 5 days. In this group, serum protein depletion was observed with particular depletion appearing at the end of the 5-day period. From calculations of protein replacement, the presence of a ready extravascular protein reserve, of a size somewhat less than the intravascular pool, was suggested. An average maximal protein replacement of 49 Gm. per day was observed during the most intensive plasmapheresis, and the data suggest that protein withdrawals should not exceed this amount if serum protein levels are to be maintained. Although no rebound of serum protein was observed, recovery after depletion required at least 2 to 4 weeks.

Plasma Proteins and Protein Synthesis in the Rat Uterus During Decidual Development

An in vivo isotope dilution experiment was designed to test the idea that the mechanism of tissue growth in the development of deciduomata, following uterine trauma in pseudopregnant rats, might involve utilization of plasma proteins by growing decidual cells. Uterine growth was induced in pseudopregnant rats 2 days after the injection of plasma protein-S35 and plasma protein- I131. The rats were autopsied after 3 and 5 days of uterine growth, when the total protein of the uterus had increased 2-fold and 5-fold, respectively. The specific activity (cpm/mg) of methionine-S35 isolated from endometrial and myometrial protein was far less than that isolated from plasma protein. Measurement of I131 in the tissue protein samples (before hydrolysis) provided corrections for contaminating plasma protein. The I131 data also indicated that extensive infiltration of plasma protein into interstitial spaces of the growing decidual uterus occurred. Nevertheless, these extravascular plasma proteins apparently remained s...

Distribution volumes of T-1824 and chromium 51 labelled red cells immediately following intravenous injection.

The difference in distribution volumes of T-1824 and Cr 51 labelled red cells is fully realized within 30 sec. after their simultaneous intravenous injection in the dog. This indicates the existence of a rapidly circulating extravascular protein pool.

Kinetics of vascular and extravascular protein exchange in unbled and bled dogs.

Unanesthetized, healthy greyhounds were infused with 25% albumin or bled, injected with I131-labeled albumin and albumin specific activities determined. It is shown that the albumin specific activity curves can be altered by changing the ratio of the vascular to extravascular albumin masses in a manner predicted from the mathematics of a two-compartment system. Increase of vascular albumin mass relative to extravascular mass results in a smaller initial disappearance of albumin specific activity from the blood stream and a faster approach to equilibrium. Decrease of vascular albumin mass relative to extravascular mass by bleeding shows that 50% of albumin replacement after hemorrhage appears to be accomplished within 24 hours. Almost all of this protein comes from the extravascular compartment. Rapid anabolism accounts for the replenishment of protein for the next 2–5 days, during and after which there is a reduced catabolism of the existing plasma albumin. The results indicate that an extravascular albumin mass exists as a separate entity and net movements may occur from this mass into the plasma when the equilibrium between the vascular and extravascular masses is disturbed.

Some relations of the lymphatic system to surgery of the mouth and jaws

1. 1. Some important relations of the lymphatic system to surgery of the mouth and jaws are presented in a brief, organized form. 2. 2. Lymphatic vessels are largely concerned with the absorption of insoluble interstitial particles by phagocytosis, colloid material, and extravascular protein material which is not normally taken up by blood capillaries. 3. 3. The walls of lymph capillaries are permeable to foreign substances of microscopic dimensions. 4. 4. Some factors determining and controlling the flow of lymph appear to be arterial and capillary blood pressure, gravity, kinetic movement, and intermittent massage. 5. 5. Blockage of lymphatic vessels produces a condition known as lymphedema; blockage may be produced by trauma, physical or chemical agents, infections, and inflammation. 6. 6. Lymph vessels have a high degree of regenerative power. 7. 7. It is believed that local lymphatic blockage as produced in acute surgical inflammation helps in isolating the lesion and protects the body from dissemination of the infection. 8. 8. It has been suggested that the lymphatic system plays an important role in maintaining the blood plasma level and aids in the process of rapid wound healing by reinforcement of plasma proteins which is necessary for the reparative process. 9. 9. The cellular content of lymph consists almost entirely of lymphocytes, and the lymphocytic content of the blood normally remains constant except for certain hourly fluctuations but does not remain in the blood stream for more than about twelve hours. 10. 10. The anatomy of the deep and superficial lymphatic system is presented as related to the mouth and jaws. 11. 11. Some common oral surgical causes of lymph node enlargement are presented with a view toward differential diagnosis of other camouflaging diseases.