Directional blood flow in pancreatic islets may be important for regulation of islet hormone release. We therefore perfused an isolated canine pancreas via the celiac artery (arterial perfusion) and then via the portal vein (venous perfusion) in the same pancreas. Basal insulin and glucagon levels and their rate of release ...

Oxygen-derived free radicals play an important role in the pathogenesis of experimental acute pancreatitis in the isolated perfused canine pancreas. We have previously found that pretreatment with allopurinol inhibits xanthine oxidase--apparently the primary source of free radical generation in this model--and prevents the initial development of pancreatitis. In these experiments, ...

The preparation for collecting lung lymph from sheep caudal mediastinal lymph node (CMN) efferent vessels is widely used to study the effects of endotoxin on lung microvascular permeability. However, there are nonpulmonary lymph vessels that drain into the CMN along with the afferent lymph vessels from the lung. Thus CMN ...

Operations were performed to cannulate the efferent duct of the popliteal node of sheep and, at the same time, the blood vascular system was removed surgically from the popliteal fossa so that the node was deprived of it blood supply. Twelve preparations were technically successful in that lymph flowed spontaneously ...

The effect of PCA on bile and lymph composition in rats was studied. It was established that secretion of bile acid decreased significantly and this resulted in reduced bile flow. In studying lymph flow and protein content, the most important observation was a decrease in the protein concentration of hepatic ...

The lymph flow of the thoracic duct, the protein content of the lymph, bile flow and bile composition are studied during the first three hours of the recirculation phase in experimental liver transplantation. It is established that the lymph flow and the protein content of the thoracic duct decrease as ...

The pancreatic microcirculation in noninbred ob/ob mice and normal controls was visualized in a fluorescence microscope and examined for responses to intravenous infusions of epinephrine or norepinephrine. Evaluations of coded video recordings revealed a smooth dose-response relationship and validated a semiquantitative method of analysis. In ob/ob mice the islet microcirculation ...

Blood flow in the anesthetized animal has been measured indirectly by plethysmography and directly with the stromuhr, venous outflow, and electromagnetic flow techniques. Tissue perfusion in the gland has been assessed qualitatively with thermocouples and quantitatively by isotope fractionation, the distribution of microspheres, hydrogen desaturation, and clearance of either 133Xe ...

Immunoreactive and bioactive corticotropin-releasing factor has been identified in the adrenal gland of dogs, rats and humans. Radioimmunoassay and immunohistochemical experiments have clearly demonstrated that localization of the peptide is confined to the adrenal medulla. CRF-containing cells have a characteristic appearance and are often found in close association with blood ...

In a previous report from this laboratory, 1 h of hypovolemia induced a significant decrease in pancreatic flow, bicarbonate and enzyme secretion. These parameters recover after restoration of blood volume, but never return to pre-shock levels. Furthermore, increasing the period of hypovolemia produced further decreases in pancreatic flow and bicarbonate ...

The caudal mediastinal lymph node (CMN) has several efferent lymph vessels in most sheep. When investigators cannulate one of the CMN efferent vessels in order to collect lung lymph, it is possible that lymph may be shunted between the cannulated vessel and other vessels which drain from the CMN into ...

In an attempt to reduce the current morbidity and mortality from acute pancreatitis, a prospective randomized multicentre trial was begun in August 1982. Part of this study involved an attempt to develop a set of prognostic indices which would identify patients with severe pancreatitis on the day of admission to ...

A vascular pathogenesis of pancreatitis has been postulated in diabetics, the aged, Ortner's Syndrome, and various low-flow states. This report studies canine pancreatic secretion in a preparation of hypovolemic shock produced by controlled hemorrhage maintained for varying durations. Pancreatic secretion was collected by cannulation of the main pancreatic duct in ...

A jaundiced dog model was made by common bile duct-inferior vena cava shunt with a silicon rubber tube. Blood bilirubin levels increased from 0.25 +/- 0.16 (SD) mg% to 15 +/- 1.4 (SD) mg%. These dog models were treated with a column containing 200 gm of macroreticular resin NK-110 which ...

Pig lymph nodes have an unusual arrangement of cortical and medullary tissue, and lack a hilus. The aim of the present study was to describe the pathways by which blood reaches these lymph nodes. Natural or synthetic latex casts were made of blood vessels of superficial inguinal, popliteal and jejunal ...

Peritoneal blood flow is closely related to the pathophysiology of peritoneal exudate during acute pancreatitis. Peritoneal blood flow was determined by the radioactive microsphere method before and 5 h after the beginning of the experiment in 39 piglets with acute hemorrhagic pancreatis, acute edemic pancreatitis, or slowly progressing hypovolemia. The ...

Experimental evidence suggests that in acute haemorrhagic pancreatitis in the dog the percentage of the cardiac output distributed to the pancreas falls. Histological evidence indicates arteriovenous shunt flow, but this has not been confirmed by flow measurements. It has recently been reported that in experimental preparations in which pancreatic blood ...

Lung lymph flow and protein transport were measured in eight anaesthetized dogs while acute hypoxic exposure (FIO2 = 0.10) was performed on prerecruited lung (achieved by an increased left atrial pressure). It was found that the lung lymph flow increase observed during hypoxia (from 71.8 +/- 47.5 to 100.8 +/- ...

Few studies have been published on the ultrastructural changes which accompany human acute pancreatitis, and these have concentrated primarily on parenchyma. The present study concentrates on extraparenchymal changes, compares acute pancreatitis occurring alone with that on a background of chronic pancreatitis, and tests for similarity with observations made previously in ...

The cause of hemodynamic changes occurring during acute pancreatitis remains obscure. Using a pig model of acute hemorrhagic pancreatitis and the reference sample method with 113Tin and 46 Scandium labelled microspheres, blood flow to organs was determined before and five hours after the induction of pancreatitis. Blood pressure, pulse rate ...

Bradykinin is an endogenous inflammatory mediator, and its mechanism of action is incompletely understood. It is controversial whether bradykinin causes a sustained increase in microvascular permeability, or has only a transient effect. In anesthetized dogs intraarterial infusion of bradykinin (0.14 to 0.54 micrograms/kg/min) produced an immediate increase in flow of ...

Left thoracic duct lymph flow rate averaged 0.077 +/- 0.003 (SD) and 0.078 +/- 0.003 ml X min-1 X kg-1 in near-term pregnant and nonpregnant sheep (P greater than 0.5). Lymph and plasma protein concentrations were unaltered in the pregnant compared with the nonpregnant animals. The thoracic duct lymph flow ...

The effect of profound hemorrhagic hypovolemia on cardiac output and pancreatic blood flow was studied in pigs with the thermodilution method and microsphere technique. Approximately 30-40% of the circulating blood volume was withdrawn slowly during 5 h. Cardiac output and pancreatic blood flow decreased by 35% and 32%, respectively. The ...

Since charge as well as size may influence the passage of plasma proteins from blood to lung lymph, we used uncharged dextrans as tracers to study the effects of hyperoxic lung injury on the molecular sieving properties of the pulmonary microcirculation in unanesthetized sheep. Polydisperse [3H]dextran was infused intravenously into ...

To understand better developmental changes in body fluid dynamics, we studied thoracic duct lymph flow in 9 newborn and 5 adult sheep. The experiments were carried out under general anaesthesia following bilateral ligation of the renal vessels and ureters. After a 30 min control period, we administered three successive 5-min ...

Blood components have been implicated as factors which modulate organ injury in acute pancreatitis. To isolate these effects we compared a standardized isolated, blood-perfused, canine pancreas model as described by Herman-Taylor and modified by Cameron with a model using fluosol, a fluorocarbon, as the perfusate. Pancreatitis was induced using partial ...

Pancreatic acinar tissue O2 tension (PO2) was measured in anesthetized rats using recessed-tip microelectrodes (tip diam 1-2 micron). Pancreatic blood flow was measured using radioactive microspheres. Volume rate of pancreatic secretion, as well as protein concentration, was also measured. Average resting PO2 was 24.8 +/- 1.6 mmHg, with relatively little ...

We present results from an improved dog model, in which lymph flows from the thorax and abdomen are separated. The effect of increased alveolar pressure on lymph flows was studied by the application of positive end expiratory pressure (PEEP). Mean (+/- SD) thoracic lymph flow in 10 dogs was 4.1 ...

In response to previous demonstrations that either surgical or chemical sympathectomy can ameliorate the severity of acute experimental pancreatitis, and suggestions that the benefits of sympathectomy are related to alterations in the absolute blood flow or the pattern of blood flow within the pancreas or splanchnic organs, we studied blood ...

Pathologic proteolysis in pancreatitis is an important clue to understand the pathophysiology in pancreatitis. Impairment of pancreatic circulation is also important in the development of severe pancreatitis. In an attempt to study some of the biochemical and circulatory events in experimental pancreatitis in the pig the following experiments were undertaken. ...

The pathways of enzyme transfer from the pancreas into the systemic circulation were analyzed in sodium taurocholate-induced acute hemorrhagic pancreatitis in the rat by estimating lipase concentrations in blood, lymph and ascites. During the first few hours of pancreatitis high enzyme levels were observed in thoracic duct lymph. However, cannulation ...

A new animal model for the selective sampling of both the thoracic and the abdominal lymph is presented. Separation of the abdominal from the thoracic lymph flow provides new information on pulmonary physiology during mechanical ventilation and is a prerequisite for studies on pulmonary lymph flow. This is underscored by ...

We investigated the intrathoracic contributions to the caudal mediastinal lymph node (CMN) efferent lymph in 12 anesthetized sheep after removing possible systemic contributions from below the diaphragm. We interrupted various pathways that may send lymph to the CMN (chest wall, esophagus, lung). Because the experiment is destructive, we did the ...

The hitherto largely unsolved problem with a biological definition of spleen versus lymph node seems possible to solve from a phylogenetic point of view. Thus, it is suggested that the spleen be defined as a hemopoietic organ which is able to filter blood with sinusoids. In contradistinction, a lymph node ...

In dogs fitted with a pancreatic cannula and a duodenal cannula the intake of a standard meal induced a significant increase in the flow of pancreatic secretion and in the output of amylase, total protein, bicarbonate and chloride. The oral administration (200 mg/day) of cimetidine to dogs was seen to ...

The aim of the present study was to evaluate the physiological role of intrapancreatic serotonergic nerves for endocrine pancreatic function. The specific uptake of [3H]5-hydroxytryptamine (5-HT) into pancreatic slices from the rat was completely abolished after an intrapancreatic injection of 5,7-dihydroxytryptamine (5,7-DHT). Since also high-affinity uptake of [3H]5-HT was absent ...

The effects of synthesized phosphodiesterase inhibitors, DM 9278 and HWA 285, on pancreatic exocrine secretion were investigated in isolated and blood-perfused canine pancreas. Close-arterial injections of DM 9278 (10-300 micrograms) and HWA 285 (300-3000 micrograms) caused dose-dependent increases in the flow rate of pancreatic juice and perfusion blood flow. Bicarbonate ...

Since precise information with respect to the microvasculature of the teleost pancreas is lacking, analysis of the so-called principal islets (Brockmann bodies) was performed in Myoxocephalus scorpius with the use of methacrylate resin for the production of cast preparations. Stereoanalytical observations indicate that the circulatory pattern in the juxtasplenic pancreatic ...

To determine the effects of a distal splenic arteriovenous fistula on endocrine function and pancreatic blood flow, 25 dogs underwent proximal pancreatectomy with the pancreatic tail left in situ and free intraperitoneal drainage of the pancreatic duct. Group A served as controls. In groups B through E, ligation of all ...

The microcirculation in the islets of Langerhans was examined by fluorescence microscopy in living mice injected with fluorescent dextran. The islet capillary network was denser and more tortuously arranged in obese-hyperglycemic (ob/ob) mice than in lean controls. Injection of norepinephrine (0.5-4.0 micrograms/kg body wt) immediately led to a pronounced inhibition ...

In this study the vascular effects of VIP were studied in connection with its secretory performances in the pancreas and the liver. In anesthetized dogs pancreatic blood flow was measured parallel with measurement of bile and pancreatic secretion. VIP was injected intravenously at intervals of 1 minute in amounts of ...

The influence of tolbutamide (20 mg/kg and 100 mg/kg i.v.) on blood flow to the entire pancreatic gland and to its endocrine tissue was studied in anaesthetized rats. Non-radioactive microspheres 8.8 micron diameter were used for determination of local blood flow rates. The islet tissue was subsequently stained intravitally with ...

By intra-arterial postmortem staining of the pancreas with hematoxylin after the administration of nonradioactive microspheres to anesthetized unfasted rats, the following values (+/-SE) were obtained: mean single islet volume, 1.00 +/- 0.12 nl (median 0.32 +/- 0.04 nl, n = 14); pancreatic intensity of perfusion, 1.18 +/- 0.14 ml X ...

In congestive heart failure, lymph flow from the cannulated thoracic duct is greatly increased. However, there has been scant data on lymph flow in the intact lymphatic system with systemic circulatory congestion. In the present study, thoracic duct and peripheral lymph flow were qualitatively determined using heated cross-thermocouples in seven ...

Microcirculatory derangements in the pancreas associated with acute pancreatitis may contribute to a low-flow state and lead to pancreatic necrosis. This study investigated the effects of glucagon, a selective mesenteric arterial dilator, on pancreatic ischemia in canine bile-trypsin-induced pancreatitis (BTP). Measurements of cardiac Index (CI), total pancreatic blood flow (QP), ...

Effects of thyrotropin-releasing hormone (TRH) on pancreatic exocrine secretion were investigated in isolated and blood-perfused canine pancreas preparations. During constant intra-arterial infusion of secretin (0.03-0.05 units/min), concentrations of protein and bicarbonate in the pancreatic juice were measured before and after intra-arterial injection of TRH (0.1-10 ng). TRH did not produce ...

The effects of isosorbide dinitrate (ISDN) on pancreatic exocrine secretion were investigated after intravenous administration in the whole animal and after close-arterial administration on the isolated and blood-perfused dog pancreas preparations. ISDN (10-100 micrograms/kg), injected into the femoral vein, caused a dose-dependent increase in flow rate of pancreatic juice and ...

This study evaluates pancreatic blood flow in the anaesthetised dog. Total flow was measured with an electromagnetic flowmeter and tissue perfusion using a Krypton-85 (85Kr) clearance technique. Cardiac output was also monitored with an electromagnetic flow probe placed on the ascending aorta. The flow and tissue perfusion in the pancreas ...

Two types of experiment using local labeling of lymph nodes with FITC showed that lymphocytes emigrate from lymph nodes, predominantly in blood in the pig and in efferent lymph in the sheep. In the first type of experiment with the pig, few cells emigrated via the lymph, while the number ...

The purpose of this study was to investigate the effects of intravenous somatostatin infusion on gastrointestinal blood flow and hormone release in conscious dogs. Gastric, duodenal, jejunal, and pancreatic blood flows, quantitated using radioactive microspheres, were significantly decreased during somatostatin infusion (200 and 500 ng/kg min), resulting in an overall ...