Prostacyclin (PGI2), a major metabolite of arachidonic acid, is widely distributed throughout the cardiovascular system and may influence vascular smooth muscle tone. To evaluate the effects of PGI2 on regional blood flow distribution in anesthetized dogs, the tracer microsphere reference sample method was used. Intravenous PGI2 infusions (0.5 and 1.0 ...

The effects of experimentally induced hyperosmolality has been studied in rats. Renal vascular pedicle ligation was performed on all animals to prevent renal clearance of the infused solute, xylose, and allow accurate ECF space determinations with 51Cr EDTA. Small volume hyperosmolar xylose infusions caused parallel elevation of the osmolality of ...

The beneficial effect of ethamsylate in maintaining the relative pancreatic blood flow in acute canine necrotizing pancreatitis has been demonstrated. This beneficial effect is a function of the action of the drug in tending to maintain pancreatic blood flow, thereby minimizing the significant decrease which normally occurs in this parameter ...

The endogenous peptides somatostatin and secretin are effective in the therapy of upper gastrointestinal tract bleeding and acute pancreatitis. The clinical effects may be partly brought about by changes in the regional blood flow. To evaluate the effects of somatostatin (50 and 100 micrograms/min over 6-8 min) and secretin (0.1 ...

Variability in the levels of epinephrine (E) and norepinephrine (NE) in adrenal vein blood is thought to preclude their usefulness in caval sampling studies for localizing abdominal pheochromocytoma. In this study we demonstrate, in three patients, that the fraction of the total catecholamine level in the adrenal effluent represented by ...

In the present study we sought evidence for the hypothesis that norepinephrine (NE) can cause constriction of lymph vessels in the canine forelimb perfused at constant flow. Mechanical venous compression (small-vein pressure approximately equal to 45 mmHg), intra-arterial infusion of histamine (16 micrograms base/min), and intra-arterial infusion of NE (16 ...

Previous studies from our laboratory indicate that the lymph flow response of the cat ileum to net volume secretion is dependent upon the mechanism involved in the secretory process, i.e, active secretion (cholera toxin) decreases lymph flow while passive fluid secretion (increased portal pressure, plasma dilution) is associated with a ...

To assess the contribution of prostaglandins (PGs) to the maintenance of vascular tone and exocrine secretion in the pancreas, the effects of several products of arachidonic acid metabolism on the blood flow and flow rate of exocrine secretion were examined in the isolated blood perfused pancreas of the pentobarbital-anesthetized dog ...

Vasodilator and hypotensive effects of (+) and (-) nicardipine were investigated in anesthetized dogs. When administered intravenously, (+) nicardipine was 3 times as potent as the (-) isomer in increasing vertebral blood flow and in lowering mean blood pressure. When injected into the vertebral artery, (+) nicardipine was also 3 ...

Popliteal and prefemoral lymphatics of sheep were cannulated, and lymph was collected before and during the course of responses to PPD and concanavalin A. Hyperemia-inducing activity (HIA) and phospholipase A2 (PLA2) were released into lymph in response to antigenic stimulation, whereas lymph plasma draining unstimulated lymph nodes had consistently little ...

The purpose of the present study was to characterize the intrinsic mechanisms involved in the regulation of blood flow and oxygenation in the totally isolated, perfused canine pancreas. Arterial pressure, venous outflow pressure, blood flow, arteriovenous oxygen difference, and capillary filtration coefficient were measured during graded arterial pressure reductions and ...

Three experiments were performed to evaluate the effects and hemodynamic changes brought about by steroids in experimental pancreatitis in dogs. The results show (1) a significant improval in survival in steroid-treated groups, (2) no difference in cardiac output or mean blood pressure between groups, (3) a decrease in relative pancreatic ...

The etiology and pathogenesis of acute necrotizing hemorrhagic pancreatitis remain controversial. Recent work has suggested that an early fall in pancreatic blood flow, causing ischemia, may be the initiating factor. Using an established rat model of hemorrhagic pancreatitis and the fractional indicator distribution technique with 86RbCl, pancreatic blood flow and ...

Blood flow to the pancreatic islets of the anesthetized rat has been measured by application of microspheres, intravital staining of the endocrine tissue by Dithizon, and induction of organ transparency by incubation in glycerol. Thus the microspheres could be counted separately in the islet tissue and in the remaining organ. ...

We measured pulmonary arterial (Ppa) and left atrial (Pla) pressures, lung lymph flow rate (QL), and protein clearance in 23 anesthetized dogs with ligation (MI) dogs or sham ligation (sham-MI dogs) of a coronary artery combined with either large transient increases in Pla or moderate steady-state increases in Pla. In ...

An optical flow-meter is described which allows precise and continuous registration of the flow of lymph from cannulated human lymph vessels. The cannula from the lymph vessel is connected to the measurement tubing of the instrument where the flow is measured by automatically monitoring the movement of an air bubble ...

For evaluation of pancreatic function testing, a peptide that releases p-aminobenzoic acid (PABA) on digestion by chymotrypsin was given to clinically normal dogs and to dogs with unexplained diarrhea. Blood concentration of PABA and percentage of PABA excretion in the urine at 6 hours after oral administration were determined. One-hour ...

Pancreatic juice was collected from rabbits treated with reserpine and from untreated controls. The volume of pancreatic juice secreted, flow rate and the bicarbonate output were all significantly reduced in the treated animals during both spontaneous flow and during secretin-stimulated flow. On the other hand, the total protein concentration, the ...

The polyvalent protease inhibitor, alpha 2-macroglobulin, may counteract a protease-mediated rheumatoid joint destruction. The elimination of the complexed inhibitor from joints was analysed in inflamed and noninflamed conditions of the knee joints in dogs. The arthritis was immunologically induced. The fate of intra-articularly injected radioactive alpha 2-macroglobulin complexes was studied ...

We examined the effects of acute hemorrhagic pancreatitis on thoracic duct lymph flow and its protein concentration. Thoracic duct lymph flow increased and the protein concentration decreased. These changes in the lymph were associated with steady decreases in arterial pressure and cardiac output and increase in systemic vascular resistance. The ...

Human pancreatic polypeptide (HPP) was infused into 6 anesthetized dogs at a constant dose of 1.0 micrograms/kg/h over 60 min. Blood samples for RIA of pancreatic polypeptide were taken repeatedly from a carotid artery, jugular vein, femoral vein, renal vein and mesenteric vein. The calculated tissue removal of HPP in ...

A dog model was used to measure the hemodynamic changes occurring during acute pancreatitis induced by intraductal injection of fresh trypsin-bile-blood mixture. Pancreatic blood flow was measured with 15-micrometer radioactive microspheres. Measurements of pancreatic adenosine triphosphate (ATP) and creatine phosphate (CP) were made under normal conditions and during acute hemorrhagic ...

Urine was observed to flow intermittently in the collecting ducts of the extrarenal papilla of antidiuretic rats. The purpose of this investigation was to test Reinking and Schmidt-Nielsen's hypothesis that intermittent flow plays an important role in the production of maximally concentrated urine. Samples of collecting duct fluid were obtained ...

In the rabbit hindleg lymph and tissue fluid were collected before and during close intraarterial infusions of histamine (2.5 and 10 micrograms/min) or bradykinin (0.4 microgram/min). Protein concentration was higher in the tissue fluid than in the lymph. During the 2h of the experiment in the control animals protein concentration ...

We studied the effects of reducing the plasma protein concentration on flow and composition of pulmonary lymph in 12 unanesthetized sheep. Whole blood was removed while red cells were returned and lactated Ringers was infused at a rate sufficient to maintain pulmonary vascular pressures at baseline values. A 44-54% reduction ...

Many investigators have used the chronic sheep lung lymph preparation to collect caudal mediastinal node (CMN) efferent lymph. These investigators have assumed that the lymph collected with the preparation is almost pure lung lymph. We examined 17 sheep for possible systemic contamination to the lymph, and in each sheep we ...

The effects of transfusion of whole blood clot emboli and aged citrated platelet-poor plasma on pulmonary capillary permeability were investigated in anesthetized sheep by continuous collection of pulmonary lymph. Changes in lymph flow and lymph-to-plasma ratios (CL/CP) for albumin and globulin were utilized to detect changes in permeability. Infusion of ...

Hind paws of anesthetized dogs were exposed to moderate continuous heat (45--52 degrees C). Lymph flow (L) was increased to 5.61 (SD 3.26) times control levels, lymph:plasma concentration ratios for total plasma protein (RT) were increased to 3.23 (SD 1.33), and for exogenous Dextran-110 (RD) to 8.41 (SD 4.00) times ...

The possible existence of an enteropancreatic circulation of amylase was investigated in the dog. Endogenous amylase concentration in pancreatic venous blood was consistently greater than that in arterial blood, indicating a net flux of amylase from the pancreas to blood. Less than 0.02% of the metabolic clearance of 125I-amylase was ...

Studies were conducted to investigate the relationship between development of fibrosis and hemodynamic changes in the pancreas in dogs. The basal blood flow rate in the atrophied, fibrotic pancreas was preserved at almost the same level as in the normal pancreas. Fibrotic pancreas responded to VIP with increased blood flow, ...

The effects of natural porcine and synthetic secretin, given by intravenous bolus or infusion, on intestinal lymph flow and protein composition in unanaesthetized rats were studied. Both forms of secretin increased lymph flow and protein output from the lymph fistula; dose-response relationships were determined. No change was observed in protein ...

In five dogs with gastric fistulas, Heidenhain pouches, and pancreatic fistulas, the effects of substance P (SP) and its C-terminal hexapeptide (SP6-11) on gastric acid and pancreatic secretions were determined under basal conditions and in response to secretory stimulation. SP or SP6-11 infused alone in graded doses (0.25-2.0 nmol.kg-1.h-1) caused ...

In dog trachea in situ, perfused arterially with blood, isoprenaline, glyceryl trinitrate and N-nitroso-N-morpholinoamino-acetonitrile (SIN-1A) given intra-arterially, decreased tracheal tone which had been elevated by neostigmine and increased tracheal blood flow. Glyceryl trinitrate and SIN-1A were more effective on the tracheal musculature than on the tracheal vasculature whereas isoprenaline was ...

Pancreatic juice flow and amylase output, and the concentrations of immunoreactive secretin in portal and peripheral blood were simultaneously determined in anesthetized rats in response to intraduodenal instillation of 1-phenyl-1-hydroxy-n-pentane (PHP), a phenyl carbinol derivative induced from one of the constituents of Curcuma. PHP stimulated both pancreatic juice flow and ...

Recovery of pancreatic juice was studied by endoscopic cannulation of the main pancreatic duct, using a double-lumen catheter and infusion of a marker solution (57Co-labeled vitamin B12) into the pancreatic duct. Juice was collected by siphonage. Tracer amounts of 91Cr were infused into the duodenum through a separate catheter attached ...

Acute pancreatitis was induced in 20 piglets. In the controls (10 piglets) no specific treatment was given, while in the experimental group the animals were treated with chlorpromazine, a potent phospholipase A2 inhibitor in vitro. Blood samples were taken from all animals for the assay of amylase, lipase, phospholipase A2, ...

We describe the feasibility of transjugular endovascular visualization and cannulation of the canine cervical thoracic duct using a flexible cholangioscope modified for lymphoscopy. The lymphoscope is composed of a prismatic side-view optic with a catheter guide channel attached by a metal cap to the terminal end. The technique has clinical ...

A technique is described for visualization of the pancreatic islets in the rat by simple dark field illumination of pieces of the frozen and thawed pancreas. By using this method, microspheres, injected for studies of the capillary blood flow, can be readily located and counted in both the islets and ...

The effects of synthetic chicken VIP (an octacosapeptide corresponding to the entire sequence of chicken VIP) on pancreatic blood flow and on systemic arterial pressure was examined in dogs. The relationship between pancreatic blood flow and systemic arterial pressure in response to synthetic chicken VIP was also investigated. Pancreatic blood ...

It has been noted that from days 18 to 22 (birth) during the second intrauterine period of morphogenesis of the rat pancreas the accumulation of enzymes increases dramatically. We studied the effect of altered maternofetal blood flow on the development of the rat pancreas during the critical second period. Our ...

Nonradioactive microspheres of various sized (mean batch diameters ranging from 6 microns ato 26 microns) were administered to unfasted rabbits under sodium pentobarbital anesthesia by a brief injection into the left ventricle. Flow rate per bead was determined by the reference organ method. After prompt death of the animal, the ...

1. Two surgical methods are described to derive bile and pancreatic juice separately by indwelling catheters in rats. 2. The secretes are always recirculated into the animals duodenum, the indwelling catheters forming an extracorporal loop. 3. The experiments are performed in the conscious animal. 4. The flow rate of the ...

Prostacyclin (PGI2), the major product of arachidonate metabolism in the gastrointestinal tract, was shown to affect gastric blood flow and gastric secretion, but it is unknown whether it also affects pancreatic secretion. This study was designed to determine the influence of PGI2 on pancreatic secretion under basal conditions and in ...

We studied the effect of varying oxygen supply on the endocrine and exocrine secretions of the isolated perfused porcine pancreas utilizing completely synthetic perfusion medium with and without the addition of erythrocytes. With synthetic medium oxygenated to a Po2 of 500 mmHg, oxygen consumption was constant for flow rates at ...

Furosemide 20 mg/kg was given intravenously to 12 anesthetized dogs with clamped renal pedicles. Thoracic duct lymph flow (TDLF) increased promptly by 38% (P less than 0.05), an increment that lasted 80 min. Because in 6 of 12 dogs there was a transient increase in splanchnic blood flow, in separate ...

A dog model was established to measure the hemodynamic changes occurring during experimental pancreatitis. The effect of treatment with Trasylol and vasopressin, beginning 60 minutes after induction of pancreatitis was assessed by their effect on the pancreatic hemodynamics. The pancreatic arterial blood flow fell by 72 per cent in the ...

There is no accepted specific treatment for acute pancreatitis in man in spite of extensive investigations. Evidence is presented based on histology, vascular and blood flow studies to support the hypothesis that acute pancreatitis is unlike most inflammatory conditions since a rapid and severe ischaemia develops in the pancreas. In ...

The WBC and per cent polymorphonuclear cells in blood increased significantly during the approximately 3 hours of the experiments. The number of lymphocytes did not change significantly. Corresponding cellular components in RD and TD lymph were not significantly different. The per cent of T-rosettes in FVB was more than three ...

Injections of non-ionic monomeric (metrizamide, C29 and iohexol) and monoacidic dimeric (ioxaglate) contrast media into the femoral artery of dogs caused significantly less increase in the rate of femoral blood flow than the more hypertonic ionic monomeric compound metrizoate at equivalent iodine concentrations. The effect of metrizoate was similar to ...

The adult respiratory distress syndrome has been associated with acute pancreatitis in 5-8% of patients. to determine, in a quantitative manner, the effects of acute, hemorrhagic pancreatitis on alveolar epithelial permeability, we studied two groups of dogs (group 1 - sham-operated, 7 dogs; group 2 - surgically induced pancreatitis, 7 ...