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J H Henriksen

Publications and source records attributed to J H Henriksen.

At least 19 recordsLinked to original sources
PubMed1999

Increased circulating leptin in alcoholic cirrhosis: relation to release and disposal.

Leptin is a cytokine peptide that decreases appetite and thereby food intake and increases energy expenditure. It is produced in fat cells, but recent animal experiments have shown expression of leptin in modified stellate hepatic cells. Because a change in circulating leptin in cirrhosis could be caused by an altered production rate, altered disposal rate, or both, the present study was undertaken to identify regions of leptin overflow into the blood stream and regions of leptin extraction. Patients with alcoholic cirrhosis (n = 16) and control patients without liver disease (n = 12) were studied during catheterization with elective blood sampling from different vascular beds. Blood samples for leptin determination (radioimmunoassay) were taken simultaneously from artery/hepatic vein, artery/renal vein, artery/iliac vein, and artery/cubital vein. Patients with cirrhosis had significantly increased circulating leptin (7.3 vs. control 2.6 ng/mL, P <.002) that correlated directly to ascitic-free body mass index (r = 0.71, P <.005). A significant renal extraction ratio of leptin was observed in control patients (0. 16) and in patients with cirrhosis (0.07), but the latter value was significantly lower than in the control patients (-44%, P <.05) and inversely correlated to serum creatinine (r = -0.60, P <.05). A significant, but equal, hepatosplanchnic extraction of leptin was observed in cirrhotic patients and control patients (0.08 vs. 0.07). In patients with cirrhosis a significant cubital venous-arterial difference in leptin was observed, but not in control patients. The iliac venous/arterial leptin ratio was significantly above 1.0 in both groups and of similar size (1.16 vs. 1.15), but a higher difference in concentration was found in the cirrhotic patients (+33%, P <.05). The spillover rates of leptin in cirrhotic patients may be even higher than estimated from the increased systemic veno-arterial gradients. In conclusion, the elevated circulating leptin in patients with cirrhosis is most likely caused by a combination of decreased renal extraction and increased release from subcutaneous abdominal, femoral, gluteal, retroperitoneal pelvic, and upper limb fat tissue areas. The hepatosplanchnic bed drained through hepatic veins could not be identified as a source of increased circulating leptin in cirrhosis, but a contribution by the portosystemic collateral flow cannot be excluded.

Adult↗
PubMed1999

Splanchnic haemodynamics after intravenous terlipressin in anaesthetised healthy pigs.

BACKGROUND/AIMS: Terlipressin is used for the treatment of bleeding oesophageal varices. We evaluated the effects of terlipressin on hepatic haemodynamics, with special focus on the interactions between portal venous flow and hepatic arterial flow over time. Secondly, we evaluated the estimated hepatic blood flow by the ICG clearance method against direct measurements of hepatic blood flow. METHODS: Eight healthy anaesthetised pigs received terlipressin 1 mg or placebo intravenously in a randomised, blind, cross-over design. Hepatic arterial flow, portal venous flow, systemic haemodynamics, and portal vein diameter were recorded simultaneously. Portal venous flow and hepatic arterial flow were measured by transit time ultrasound flowmetry. Estimated hepatic blood flows at baseline and after terlipressin were compared with the sum of the portal venous flow and hepatic arterial flow. RESULTS: Portal venous flow decreased significantly 5 min after administration of terlipressin (p<0.05). At 30 min it had decreased by 34% (p<0.01) and the hepatic arterial flow had increased by 81% (p<0.01). The estimated hepatic blood flow and the hepatic blood flow decreased by 23% (p<0.015). At baseline the estimated hepatic blood flow and the hepatic blood flow correlated significantly (r=0.85, p<0.01), but this correlation disappeared after administration of terlipressin (r=0.06, p=ns). The hepatic blood flow was 12% higher than the estimated hepatic blood flow before and after terlipressin. CONCLUSIONS: Terlipressin decreased the portal venous flow, hepatic blood flow, and estimated hepatic blood flow significantly and was accompanied by a substantial increase in hepatic arterial flow. The estimated hepatic blood flow and hepatic blood flow were strongly correlated at baseline, but after terlipressin the correlation disappeared.

Anesthesia↗
PubMed1999

Endoscopic ultrasound duplex scanning for measurement of portal venous flow. Validation against transit time ultrasound flowmetry in pigs.

BACKGROUND: Endoscopic ultrasound (EUS) is a new technique that makes it possible to measure portal venous flow when transabdominal ultrasound fails. As the technique has not been evaluated previously, we compared simultaneous measurements of portal venous flow using EUS Doppler with that of transit time ultrasound (TTU) in healthy pigs. The ability of EUS to detect changes in the portal venous flow after pharmacologic intervention was also investigated. METHODS: Six anaesthetized pigs were studied. Portal venous flow was measured simultaneously by EUS duplex scanning, using a Pentax FG-32UA echoendoscope connected to a Hitachi EUB 515-A ultrasound scanner, and by TTU with a Cardiomed CM 4000 flowmeter probe placed on the portal vein. Terlipressin, 1 mg, and placebo were administered in a blind, randomized, crossover design. Measurements were taken at base line and 30 min after each drug administration. RESULTS: Portal venous flow measured by EUS flowmetry and TTU flowmetry correlated significantly (R = 0.92, P < 0.001, n = 18). The limits of agreement in a Bland-Altman plot were from -0.262 l/min to +0.164 l/min. The change in portal venous flow after terlipressin measured by EUS and TTU correlated significantly (R = 0.88, P < 0.05, n = 6). All values used for analyses were the means of five repeated measurements. CONCLUSIONS: EUS measures portal venous flow with an acceptable correlation and agreement with TTU in anaesthetized pigs. The method is capable of monitoring the effects of pharmacologic intervention on the portal system.

Animals↗
PubMed1999

Effects on plasma angiotensin-converting enzyme activity and circulating renin of lisinopril and enalapril alone and in combination with propranolol in healthy volunteers.

The effects on plasma angiotensin-converting enzyme activity and renin activity of the two long-acting angiotensin-converting enzyme inhibitors, lisinopril and enalapril, alone and in combination with propranolol were studied. In an open, randomised, cross-over design 12 healthy volunteers received orally enalapril 20 mg alone, enalapril 20 mg in combination with propranolol 80 mg, lisinopril 20 mg alone, and lisinopril 20 mg in combination with propranolol 80 mg. Plasma angiotensin-converting enzyme activity and plasma renin activity were measured for 24 h after each treatment period. Lisinopril and enalapril reduced plasma angiotensin converting enzyme activity substantially and equally at six hr (-70%, P<0.05) and 12 hr (-65%, P<0.05), irrespective of combination with propranolol. At 24 hr plasma angiotensin-converting enzyme activity remained significantly suppressed only after lisinopril (-60%, P<0.05). Plasma renin activity increased almost ten times after ingestion of both angiotensin-converting enzyme inhibitors, but the effect lasted significantly longer after lisinopril than after enalapril. Beta-Adrenergic blockade blunted the effect on the increase in plasma renin activity induced by both angiotensin-converting enzyme inhibitors. Our results show that the effect of lisinopril on plasma angiotensin-converting enzyme activity and plasma renin activity lasted longer than that of enalapril. beta-Adrenergic blockade suppressed the effect on elevated plasma renin activity, but did not influence the effect of angiotensin-converting enzyme inhibitors on plasma angiotensin-converting enzyme activity.

Adrenergic beta-Antagonists↗
PubMed1999

Elevated carboxy terminal cross linked telopeptide of type I collagen in alcoholic cirrhosis: relation to liver and kidney function and bone metabolism.

BACKGROUND: The carboxy terminal cross linked telopeptide of type I collagen (ICTP) has been put forward as a marker of bone resorption. Patients with alcoholic liver disease may have osteodystrophy. AIMS: To assess circulating and regional concentrations of ICTP in relation to liver dysfunction, bone metabolism, and fibrosis. METHODS: In 15 patients with alcoholic cirrhosis and 20 controls, hepatic venous, renal venous, and femoral arterial concentrations of ICTP, and bone mass and metabolism were measured. RESULTS: Circulating ICTP was higher in patients with cirrhosis than in controls. No overall significant hepatic disposal or production was found in the patient or control groups but slightly increased production was found in a subset of patients with advanced disease. Significant renal extraction was observed in the controls, whereas only a borderline significant extraction was observed in the patients. Measurements of bone mass and metabolism indicated only a mild degree of osteodystrophy in the patients with cirrhosis. ICTP correlated significantly in the cirrhotic patients with hepatic and renal dysfunction and fibrosis, but not with measurements of bone mass or metabolism. CONCLUSIONS: ICTP is highly elevated in patients with cirrhosis, with no detectable hepatic net production or disposal. No relation between ICTP and markers of bone metabolism was identified, but there was a relation to indicators of liver dysfunction and fibrosis. As the cirrhotic patients conceivably only had mild osteopenia, the elevated ICTP in cirrhosis may therefore primarily reflect liver failure and hepatic fibrosis.

Adult↗
PubMed1998

[Scientific activities in departments of clinical physiology/nuclear medicine in Denmark during the period 1989-1994. A bibliometric analysis of the "impact" and citation frequency].

This study reports a bibliometric analysis of 860 scientific publications of which 763 are papers in scientific journals emanating from departments of clinical physiology and nuclear medicine in Denmark in the years 1989-1994. The number of publications decreased significantly over time. The 763 papers were published in 239 different scientific journals, 80% in journals with an official "impact factor". The average impact per paper remained almost constant over time and was significantly above the national average. A close relationship was found between the number of papers from a department and its cumulated impact. In an analysis of 217 papers a direct relation was found between the journal impact factor and the citation factor. A linear relation was found between cumulated citations and time, and the number of citations per year reached a maximum 3-7 years after publication, whereas the general maximum for all medical specialties is 2-3 years. It is concluded that the total number of scientific papers from Danish departments of clinical physiology & nuclear medicine fell in the years 1989-1991, but the impact per paper was almost constant and above the national average. There seems to be a good agreement between journal impact factor and overall citation frequency in papers from clinical physiology & nuclear medicine.

Bibliometrics↗
PubMed1998

[Decompensation].

Fluid and sodium retention with peripheral oedema and ascites are often seen in decompensated patients with diseases of the liver, kidney and heart and in malignancies. Despite a careful clinical examination including relevant biochemical tests, decompensation is associated with diagnostic challenges. Two cases are presented where a haemodynamic investigation of the splanchnic and systemic circulation contributed to the establishment of a correct diagnosis, and the advantages of this diagnostic tool are discussed.

Ascites↗
PubMed1998

Neurohumoral fluid regulation in chronic liver disease.

Impaired homeostasis of the blood volume, with increased fluid and sodium retention, is a prevailing element in the deranged systemic and splanchnic haemodynamics in patients with liver disease. In this review, some basic elements of the circulatory changes that take place and of neurohumoral fluid regulation are outlined in order to provide an update of recent investigations on the neuroendocrine compensation of circulatory and volume dysfunction in chronic liver disease. The underlying pathophysiology is a systemic vasodilatation in which newly described potent vasoactive substances such as nitric oxide and vasodilating peptides seem to play an important role. The development of central hypovolaemia and activation of potent vasoconstricting systems such as the renin-angiotensin-aldosterone system and the sympathetic nervous system lead to a hyperdynamic circulation with increased heart rate and cardiac output. Moreover, patients exhibit an autonomic dys- and hyperfunction with vascular hyporeactivity to pressor stimuli. The circulatory dysfunction may be part of a multiorgan failure with disturbed haemodynamics of various vascular beds, including those of the splanchnic system, kidneys, brain and lungs. It is still an enigma why patients with chronic liver disease are at the same time overloaded and functional hypovolaemic with a hyperdynamic, hyporeactive circulation. Further research is needed to find the solution to this apparent haemodynamic conflict concerning the abnormal neurohumoral fluid regulation in chronic liver disease.

Adrenomedullin↗
PubMed1998

Arterial hypoxaemia in cirrhosis: fact or fiction?

BACKGROUND: Although low arterial oxygen tension (Po2) has been claimed to occur in one to two thirds of patients with cirrhosis, hypoxaemia appears to be rare in clinical practice. AIMS: To assess the frequency of arterial hypoxaemia in cirrhosis in relation to clinical and haemodynamic characteristics. PATIENTS: One hundred and forty two patients with cirrhosis without significant hepatic encephalopathy (grades 0-I) (41 patients in Child class A, 57 in class B, and 44 in class C) and 21 patients with hepatic encephalopathy. RESULTS: Mean Po2 in kPa was 11.3 in Child class A, 10.8 in class B, 10.6 in class C, and 10.6 in patients with encephalopathy (p < 0.05). The fraction of patients with Po2 below the lower normal limit of 9.6 kPa was 10%, 28%, 25%, and 43%, respectively in class A, B, C, and in patients with encephalopathy (p < 0.05). Oxygen saturation (So2) in these groups was respectively: 96%, 96%, 96%, and 93% (NS). So2 was below the lower limit of 92% in 0%, 9%, 7%, and 24% (p < 0.05). In patients without hepatic encephalopathy, a multivariate regression analysis revealed that independent determinants of a low Po2 were a high arterial carbon dioxide tension, a low systemic vascular resistance, and a low indocyanine green clearance (p < 0.0001). CONCLUSION: The prevalence of arterial hypoxaemia in cirrhosis is about 22% in patients without encephalopathy, but it varies from 10-40% depending on the degree of hepatic dysfunction. Arterial hypoxaemia in patients with cirrhosis of differing severity seems lower than previously reported, and patients with severe arterial hypoxaemia are rare.

Adult↗
PubMed1998

Haemodynamics and fluid retention in liver disease.

Patients with cirrhosis and portal hypertension exhibit characteristic haemodynamic changes with a hyperkinetic systemic circulation, an abnormal distribution of the blood volume and neurohumoral dysregulation. Their plasma and noncentral blood volumes are increased, but the central and arterial blood volume and systemic vascular resistance are decreased. A systemic and splanchnic vasodilatation is of pathogenic importance to the low systemic vascular resistance and abnormal volume distribution. These are important elements in the development of the low arterial blood pressure and hyperkinetic circulation in cirrhosis. Various vasodilators such as nitric oxide, calcitonin gene-related peptide, and adrenomedullin are among potential candidates in the vasodilatation in cirrhosis. Besides reflex induced enhanced sympathetic nervous activity, activation of the renin-angiotensin-aldosterone system, and elevated circulation vasopressin, endothelin-1 may also be implicated in the haemodynamic counter-regulation in cirrhosis. Recent research has focused on the assertion that the haemodynamic and neurohumoral abnormalities in cirrhosis are part of a general circulatory dysfunction, influencing the course of the disease with reduction of kidney function and sodium-water retention as the outcome.

Animals↗