Human atrial natriuretic factor and renin-aldosterone in paracetamol induced fulminant hepatic failure

Acetaminophen Increases Aldosterone Secretion While Suppressing Cortisol and Androgens: A Possible Link to Increased Risk of Hypertension

BACKGROUND

Acetaminophen (paracetamol) is a widely used analgesic and antipyretic drug. Potential side effects are of public health concern, and liver toxicity from acute overdose is well known. More recently, a regular use of acetaminophen has been associated with an increased risk of hypertension.

METHODS

We investigated effects of acetaminophen on steroidogenesis as a possible mechanism for the hypertensive action by using the human adrenocortical cell line, H295R. Cells were treated with 0.1, 0.5, and 1mM of acetaminophen for 24 hours, and secretion of steroids and gene expression of key steps in the steroidogenesis were investigated.

RESULTS

Progesterone and aldosterone secretion were increased dose dependently, while secretion of 17α-OH-progesterone and cortisol as well as dehydroepiandrosterone and androstenedione was decreased. CYP17α-hydroxylase activity, assessed by the ratio 17α-OH-progesterone/progesterone, and CYP17-lyase activity, assessed by the ratio androstenedione/17α-OH-progesterone, were both dose-dependently decreased by acetaminophen. No effects were revealed on cell viability. Treatment of cells with 0.5mM of acetaminophen did not cause any effects on the expression of 10 genes in the steroidogenic pathways.

CONCLUSIONS

The pattern of steroid secretion caused by acetaminophen can be explained by inhibition of CYP17A1 enzyme activity. A decreased secretion of glucocorticoids and androgens, as demonstrated by acetaminophen, would, in an in vivo situation, induce adrenocorticotropic hormone release via negative feedback in the hypothalamic-pituitary-adrenal axis and result in an upregulation of aldosterone secretion. Our results suggest a novel possible mechanism for acetaminophen-induced hypertension, which needs to be further elucidated in clinical investigations.

Does the use of insulin in a patient with liver dysfunction increase water retention in the body, i.e. cause insulin oedema?

A 68-year-old female with mild diabetes mellitus was admitted because of acute liver dysfunction due to autoimmune hepatitis. While 40 mg/day of prednisolone improved hepatic dysfunction dramatically, her diabetic milieu deteriorated seriously. The induced hyperglycaemia could not be controlled sufficiently, despite a high dose of insulin (> 110 units/day), suggesting the existence of insulin insensitivity and hyperinsulinaemia. Soon after introduction of insulin therapy, she developed severe anasarca, including marked peripheral oedema, ascites and pleural effusion. Anasarca eventually subsided within 4 weeks with the use of a diuretic agent. We conjectured that the side effects of insulin, such as anti-natriuresis and increased vascular permeability, might be pronounced in the presence of the hepatic dysfunction that accompanies insulin insensitivity, hyperinsulinaemia and hypoalbuminaemia.

Fulminant hepatic failure

Fulminant hepatic failure is a disease of varied causes and a high mortality rate. A sudden onset, jaundice, hepatic encephalopathy, and multiorgan failure are the hallmarks of this syndrome. The management of patients with FHF requires a multidisciplinary approach and intense monitoring. The availability of liver transplantation has provided the means to rescue such patients from near-certain death. Early prognostication and timely availability of donor livers are requirements for a successful outcome. The development of effective artificial liver support devices may greatly prolong the window of opportunity to provide a donor liver, or alternatively, to allow the native liver to regenerate.

Treatment of hepatic failure--1996: current concepts and progress toward liver dialysis

Liver failure, especially in its acute form, is a medical emergency that quickly leads to failure of multiple other organs. Many of these end-organ failures can be supported temporarily by drugs or medical devices, but the support is invariably short-lived if liver function is not restored. In most instances, liver function can only be restored by transplantation, although patients with acute disease have the potential to recover by regeneration ("spontaneous recovery"). Unfortunately, spontaneous recovery from acute liver failure is uncommon, so the two most important aspects of patient management are highly skilled intensive care and early recognition of patients in need of liver transplantation. Even under these circumstances, the mortality of liver failure remains high because we have no easy way of replacing liver function on demand and donor organs are becoming increasingly difficult to obtain in time. The development of techniques for liver assist offer the possibility that patients with liver failure will become a simple management problem, analogous to the options available in the treatment of acute and chronic renal failure.

Human natriuretic factor in cirrhotic patients undergoing orthotopic liver transplantation

We measured the plasma levels of atrial natriuretic factor (ANF) during orthotopic liver transplantation (OLT) in eight adult patients with cirrhosis and ascites. The aim of this study was to determine whether significant differences in ANF concentration may be detected during the individual phases of OLT and to correlate these changes with hemodynamics. In each patient a hemodynamic assessment was achieved using a Swan-Ganz fiber optic catheter for continuous monitoring of cardiac output (CO), systemic vascular resistance index (SVRI), right filling pressure as assessed by central venous pressure (CVP), and left filling pressure by means of pulmonary arterial wedge pressure (PAWP). During reperfusion a clear-cut increase in ANF values was observed (P < 0.05). Concurrently, an increase in CVP (P < 0.05) and a decrease in SVRI were observed without any significant increase in diuresis. These data suggest that ANF might play a role in the development of the reperfusion syndrome.

The role of atrial natriuretic peptide (ANP) in chronic liver disease

The role of atrial natriuretic peptide (ANP) and potential defects of ANP in liver disease are reviewed. Patients with cirrhosis of the liver show no decrease of ANP plasma concentrations nor changes in the pattern of ANP immunoreactivity nor changes of splanchnic ANP clearance. The renal effects of exogenously administered as well as endogenously released ANP are blunted in cirrhosis, in particular in patients with ascites. This seems due to increased activity of sodium-retaining hormonal systems and changes of the renal ANP receptor status. Pharmacological inhibition of ANP-degradation or clearance may yield therapeutic potential.