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Konstantinidis AO, Adamama-Moraitou KK, Patsikas MN, Papazoglou LG. Congenital Portosystemic Shunts in Dogs and Cats: Treatment, Complications and Prognosis. Vet Sci 2023; 10:vetsci10050346. [PMID: 37235429 DOI: 10.3390/vetsci10050346] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Revised: 05/02/2023] [Accepted: 05/10/2023] [Indexed: 05/28/2023] Open
Abstract
Congenital portosystemic shunts (CPSS) are a common vascular anomaly of the liver in dogs and cats. Clinical signs of CPSS are non-specific and may wax and wane, while laboratory findings can raise the clinical suspicion for CPSS, but they are also not specific. Definitive diagnosis will be established by evaluation of liver function tests and diagnostic imaging. The aim of this article is to review the management, both medical and surgical, complications, and prognosis of CPSS in dogs and cats. Attenuation of the CPSS is the treatment of choice and may be performed by open surgical intervention using ameroid ring constrictors, thin film banding, and partial or complete suture ligation or by percutaneous transvenous coil embolization. There is no strong evidence to recommend one surgical technique over another. Medical treatment strategies include administration of non-absorbable disaccharides (i.e., lactulose), antibiotics, and dietary changes, and are indicated for pre-surgical stabilization or when surgical intervention is not feasible. After CPSS attenuation, short- and long-term post-surgical complications may be seen, such as post-operative seizures and recurrence of clinical signs, respectively. Prognosis after surgical attenuation of CPSS is generally favorable for dogs and fair for cats.
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Affiliation(s)
- Alexandros O Konstantinidis
- Companion Animal Clinic (Medicine Unit), School of Veterinary Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki, 54627 Thessaloniki, Greece
| | - Katerina K Adamama-Moraitou
- Companion Animal Clinic (Medicine Unit), School of Veterinary Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki, 54627 Thessaloniki, Greece
| | - Michail N Patsikas
- Laboratory of Diagnostic Imaging, School of Veterinary Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki, 54627 Thessaloniki, Greece
| | - Lysimachos G Papazoglou
- Companion Animal Clinic (Surgery and Obstetrics Unit), School of Veterinary Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki, 54627 Thessaloniki, Greece
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Loomes K. Anaesthesia and analgesia considerations for foals with confirmed or suspected portosystemic shunt. EQUINE VET EDUC 2021. [DOI: 10.1111/eve.13249] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Affiliation(s)
- K. Loomes
- Rainbow Equine Hospital Old Malton, North Yorkshire UK
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3
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Or M, Devriendt N, Kitshoff AM, Peremans K, Vandermeulen E, Paepe D, Polis I, Martlé V, de Rooster H. Ammonia concentrations in arterial blood, venous blood, and cerebrospinal fluid of dogs with and without congenital extrahepatic portosystemic shunts. Am J Vet Res 2017; 78:1313-1318. [DOI: 10.2460/ajvr.78.11.1313] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Ahn JO, Li Q, Lee YH, Han SM, Hwang CY, Youn HY, Chung JY. Hyperammonemic hepatic encephalopathy management through L-ornithin-L-aspartate administration in dogs. J Vet Sci 2017; 17:431-3. [PMID: 26726023 PMCID: PMC5037314 DOI: 10.4142/jvs.2016.17.3.431] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2015] [Revised: 11/09/2015] [Accepted: 12/30/2015] [Indexed: 12/02/2022] Open
Abstract
Seventeen dogs were treated with L-ornithin-L-aspartate (LOLA; experimental group). Three dogs were treated with lactulose recognized therapy (control group). Following LOLA administration, 15 dogs experienced a significant decrease in ammonia level (p < 0.05) and showed clinical signs of improvement. However, there were no clinical signs of improvement in two dogs, even though the ammonia level decreased. Conversely, the clinical signs of the control group also improved and the ammonia level decreased, although these changes were not significant (p > 0.05). These results suggest that LOLA is an effective drug to treat hyperammonemia in veterinary medicine.
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Affiliation(s)
- Jin-Ok Ahn
- Department of Veterinary Internal Medicine, College of Veterinary Medicine, Seoul National University, Seoul 08826, Korea
| | - Qiang Li
- Department of Veterinary Internal Medicine, College of Veterinary Medicine, Seoul National University, Seoul 08826, Korea
| | - Young-Heun Lee
- Department of Veterinary Internal Medicine, College of Veterinary Medicine, Seoul National University, Seoul 08826, Korea
| | - Sei-Myoung Han
- Department of Veterinary Internal Medicine, College of Veterinary Medicine, Seoul National University, Seoul 08826, Korea
| | - Cheol-Yong Hwang
- Department of Veterinary Internal Medicine, College of Veterinary Medicine, Seoul National University, Seoul 08826, Korea
| | - Hwa-Young Youn
- Department of Veterinary Internal Medicine, College of Veterinary Medicine, Seoul National University, Seoul 08826, Korea
| | - Jin-Young Chung
- Department of Veterinary Internal Medicine and Institute of Veterinary Science, College of Veterinary Medicine, Kangwon National University, Chuncheon 24341, Korea
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Butterworth RF. Neurosteroids in hepatic encephalopathy: Novel insights and new therapeutic opportunities. J Steroid Biochem Mol Biol 2016; 160:94-7. [PMID: 26589093 DOI: 10.1016/j.jsbmb.2015.11.006] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/23/2015] [Revised: 10/22/2015] [Accepted: 11/09/2015] [Indexed: 12/13/2022]
Abstract
Hepatic encephalopathy (HE) is a serious neuropsychiatric disorder resulting from liver failure. Symptoms of HE include mild cognitive impairment, stupor and coma. Morphological changes to neuroglia (both astrocytes and microglia) occur in HE consisting of cytotoxic brain edema (astrocyte swelling) in acute liver failure and Alzheimer type-2 astrocytosis in cirrhosis. Visual-evoked responses in animals with liver failure and HE manifest striking similarities to those in animals treated with agonists of the GABA-A receptor complex. Neurosteroids are synthesized in brain following activation of translocator protein (TSPO), a mitochondrial neuroglial cholesterol-transporter protein. TSPO sites are activated in both animal models of HE as well as in autopsied brain tissue from HE patients. Activation of TSPO sites results in increased cholesterol transport into the mitochondrion followed by stimulation of a metabolic pathway culminating in the synthesis of allopregnanolone (ALLO) and tetrahydrodeoxycorticosterone (THDOC), neurosteroids with potent positive allosteric modulatory action on the GABA-A receptor complex. Concentrations of ALLO and THDOC in brain tissue from mice with HE resulting from toxic liver injury are sufficient to induce sedation in animals of the same species and significant increases in concentrations of ALLO have been reported in autopsied brain tissue from cirrhotic patients with HE leading to the proposal that "increased GABAergic tone" in HE results from that increased brain concentrations of this neurosteroid. Agents with the potential to decrease neurosteroid synthesis and/or prevent their modulatory actions on the GABA-A receptor complex may provide novel approaches to the management and treatment of HE. Such agents include indomethacin, benzodiazepine receptor inverse agonists and a novel series of compounds known as GABA-A receptor-modulating steroid antagonists (GAMSA).
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Lidbury JA, Cook AK, Steiner JM. Hepatic encephalopathy in dogs and cats. J Vet Emerg Crit Care (San Antonio) 2016; 26:471-87. [PMID: 27060899 DOI: 10.1111/vec.12473] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2014] [Revised: 11/04/2014] [Accepted: 11/07/2014] [Indexed: 12/29/2022]
Abstract
OBJECTIVE To comparatively review the pathogenesis, clinical presentation, diagnosis, and management of hepatic encephalopathy (HE) in dogs and cats. DATA SOURCES The Medline database was searched for articles related to HE in people, dogs, and cats. Articles published within the last 5 years were given special importance. HUMAN DATA SYNTHESIS The pathogenesis of HE is complex and incompletely understood, but ammonia appears to play a central role. Hyperammonemia leads to accumulation of glutamine in astrocytes, with subsequent astrocyte swelling and neurological dysfunction. The development of HE in patients with hepatic cirrhosis is a poor prognostic indicator. The fermentable disaccharide lactulose and the antimicrobial rifaximin are US Food and Drug Administration approved treatments for human HE. Severe protein restriction is no longer recommended for patients with this condition. VETERINARY DATA SYNTHESIS HE is often associated with portosystemic shunting in dogs and cats. Ammonia plays a central role in the pathogenesis of HE in dogs and cats, but other factors such as manganese and endogenous benzodiazepines may also contribute. Recently, a soy protein-based diet was found to be beneficial in treating canine HE. Severe dietary protein restriction is likely to be detrimental in affected animals. There have been no clinical trials of drugs routinely used in the management HE in veterinary medicine, but lactulose and antimicrobials such as metronidazole are well-established treatments. CONCLUSIONS HE is a potentially life-threatening condition that is probably underdiagnosed in companion animals. Although various treatment recommendations have been proposed, there is a lack of evidence in the veterinary literature regarding optimal strategies for the management of this condition. As our understanding of the pathogenesis of HE in dogs and cats evolves, novel diagnostic tests and therapeutic agents may become available.
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Affiliation(s)
- Jonathan A Lidbury
- Department of Veterinary Small Animal Clinical Sciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX, 77843
| | - Audrey K Cook
- Department of Veterinary Small Animal Clinical Sciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX, 77843
| | - Jörg M Steiner
- Department of Veterinary Small Animal Clinical Sciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX, 77843
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Woodford NS, Hotson Moore A, Renfrew H, Tulloch L, Casey M. Surgical management of an extrahepatic portosystemic shunt in a foal: A multidisciplinary problem. EQUINE VET EDUC 2015. [DOI: 10.1111/eve.12524] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Affiliation(s)
| | - A. Hotson Moore
- Bath Referrals; Rosemary Lodge Veterinary Hospital; Wellsway UK
| | - H. Renfrew
- VetCT Specialists; St Johns Innovation Centre; Cambridge UK
| | | | - M. Casey
- Faculty of Veterinary Medicine; University of Glasgow; UK
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Liver. CANINE AND FELINE GASTROENTEROLOGY 2013. [PMCID: PMC7161409 DOI: 10.1016/b978-1-4160-3661-6.00061-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
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Hug S, Guerrero T, Makara M, Kummer M, Grest P, Bettschart R, Schwarzwald C. Diagnosis and Surgical Cellophane Banding of an Intrahepatic Congenital Portosystemic Shunt in a Foal. J Vet Intern Med 2011; 26:171-7. [DOI: 10.1111/j.1939-1676.2011.00837.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2011] [Revised: 09/13/2011] [Accepted: 10/10/2011] [Indexed: 11/26/2022] Open
Affiliation(s)
| | | | | | | | - P. Grest
- Institute of Veterinary Pathology; Vetsuisse Faculty; University of Zurich; Zurich; Switzerland
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Altered glial–neuronal crosstalk: Cornerstone in the pathogenesis of hepatic encephalopathy. Neurochem Int 2010; 57:383-8. [DOI: 10.1016/j.neuint.2010.03.012] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2009] [Accepted: 03/23/2010] [Indexed: 01/09/2023]
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Müller JMV, Schulze M, Herder V, Lautenschläger I, Baumgärtner W, Feige K. Ataxia and weakness as uncommon primary manifestations of hepatic encephalopathy in a 15-year-old trotter gelding. EQUINE VET EDUC 2010. [DOI: 10.1111/j.2042-3292.2010.00132.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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12
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Proot S, Biourge V, Teske E, Rothuizen J. Soy protein isolate versus meat-based low-protein diet for dogs with congenital portosystemic shunts. J Vet Intern Med 2009; 23:794-800. [PMID: 19496910 DOI: 10.1111/j.1939-1676.2009.0327.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
BACKGROUND Both presurgical preparation and long-term support of nonoperable dogs with congenital portosystemic shunts (CPSS) require optimal dietary management. Studies suggested that protein source may play an important role, with vegetable and dairy protein sources having better effects on hepatic encephalopathy (HE) than meat proteins. OBJECTIVES Determine whether a low-protein test diet with soy as its main protein source results in better scores than a control diet with the same composition but with poultry as its main protein source in dogs with CPSS. METHODS In a double-blind cross-over study, 16 dogs received each diet for 4 weeks. Dogs in group T first received the test diet and then the control diet, whereas dogs in group C were fed the diets in the opposite order. Different variables (body weight, body condition score, HE score, fecal score, CBC, plasma tests of liver function including NH3, and coagulation tests) were measured at the start of the study and after completion of each diet. RESULTS One-way repeated measures ANOVA was performed. Plasma NH3 was significantly lower after the test diet than after the control diet. The test diet also resulted in significantly higher fibrinogen concentrations and lower prothrombin times. The HE score improved with both diets, with no significant difference between the 2 diets. CONCLUSIONS Both diets achieved a significant improvement in HE score. The influence of the soy-based diet on plasma NH3 concentration and coagulation parameters suggests that such a diet decreases the risk for HE and gives better support of liver function.
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Affiliation(s)
- S Proot
- Department of Clinical Sciences of Companion Animals, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands.
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Abstract
Hepatic encephalopathy (HE) remains a severe neuropsychiatric complication of liver failure. Neuropathological evaluation of material from patients who died in hepatic coma reveals morphologic changes primarily to astrocytes (cytotoxic edema, Alzheimer Type II astrocytosis) accompanied by discreet neuronal changes. Liver failure results in the accumulation in brain of neurotoxic compounds (ammonia, manganese, proinflammatory cytokines, mercaptans, octanoic acid) that may act synergistically to impair neuropsychiatric function. Ammonia and manganese act synergistically to activate mitochondrial benzodiazepine receptors leading to increased production of neuroactive steroids, many of which (allopregnanolone, THDOC) have potent neuroinhibitory properties resulting from activation of a neuromodulatory site on the GABA-A receptor ("increased GABAergic tone"). New evidence demonstrates that proinflammatory cytokines such as tumor necrosis factor alpha (TNFalpha) and the interleukins (IL-1beta, and IL-6) are produced not only by the liver but also by the brain in liver failure. Ammonia and proinflammatory cytokines generated either by intercurrent infection or from hepatocyte necrosis in liver failure act synergistically to decrease the capacity of astrocytes to remove glutamate from the brain extracellular space leading to the activation of glutamate (NMDA) receptors that in turn results in alterations of cell-cell signalling and hyperexcitability. Therapy for HE continues to rely heavily on strategies aimed at reduction of gut ammonia production, increased ammonia removal and, ultimately, liver transplantation. A more complete understanding of pathophysiologic mechanisms has led to novel potential strategies aimed at decreasing both GABAergic tone, glutamate (NMDA) receptor activation and proinflammatory cytokines. Such strategies hold promise for new therapies for HE in the near future.
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Affiliation(s)
- Roger F Butterworth
- Neuroscience Research Unit (CHUM), University of Montreal, Montreal, QC, Canada
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Gallagher AE, Grant DC, Noftsinger MN. Coma and respiratory failure due to moxidectin intoxication in a dog. J Vet Emerg Crit Care (San Antonio) 2008. [DOI: 10.1111/j.1476-4431.2007.00248.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Ahboucha S, Butterworth RF. The neurosteroid system: implication in the pathophysiology of hepatic encephalopathy. Neurochem Int 2007; 52:575-87. [PMID: 17610999 DOI: 10.1016/j.neuint.2007.05.004] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2007] [Revised: 04/23/2007] [Accepted: 05/03/2007] [Indexed: 01/09/2023]
Abstract
Hepatic encephalopathy (HE) is a serious cerebral complication of both acute and chronic liver failure. In acute liver failure, astrocytes undergo swelling which results in increased intracranial pressure and may lead to brain herniation and death. In chronic liver failure, Alzheimer-type II astrocytosis is the characteristic neuropathologic finding. Patients with liver failure manifest severe alterations of their quality of life including sleep disorders as well as memory, learning, and locomotor abnormalities. Neurosteroids (NS) are synthesized in the brain mainly by astrocytes independent of peripheral steroidal sources (adrenals and gonads) and are suggested to play a role in the pathogenesis of HE. NS bind and modulate different types of neural receptors; effects on the gamma amino butyric acid (GABA)-A receptor complex are the most extensively studied. For example, the NS tetrahydroprogesterone (allopregnanolone), and tetrahydrodeoxycorticosterone (THDOC) are potent positive allosteric modulators of the GABA-A receptor. As a consequence of modulation of these receptors, NS stimulate inhibitory neurotransmission in the CNS, and neuroinhibitory changes including "increased GABA-ergic tone" have been suggested as pathophysiological mechanisms in HE. Moreover, some NS bind to intracellular receptors through which they also regulate gene expression, and there is substantial evidence confirming that expression of genes coding for key astrocytic and neuronal proteins are altered in HE. This review summarizes findings consistent with the involvement of NS in human and experimental HE.
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Affiliation(s)
- Samir Ahboucha
- Neuroscience Research Unit, Hôpital Saint-Luc (CHUM), 1058 St-Denis, Montreal, Quebec, Canada H2X 3J4
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Ahboucha S, Coyne L, Hirakawa R, Butterworth RF, Halliwell RF. An interaction between benzodiazepines and neuroactive steroids at GABA A receptors in cultured hippocampal neurons. Neurochem Int 2006; 48:703-7. [PMID: 16487630 DOI: 10.1016/j.neuint.2005.12.006] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2005] [Revised: 12/13/2005] [Accepted: 12/15/2005] [Indexed: 11/21/2022]
Abstract
Neurosteroids are modulators of several receptors and ion channels and are implicated in the pathophysiology of several neuropsychiatric diseases including hepatic encephalopathy (HE). The neurosteroid, allopregnanolone, a positive allosteric modulator of GABA(A) receptors, accumulates in the brains of HE patients where it can potentiate GABA(A) receptor-mediated responses. Attenuation of the effects of neurosteroids on GABA-ergic neurotransmission is therefore of interest for the management of HE. In the present study, we determined the effect of the benzodiazepine partial inverse agonist, Ro15-4513, and the benzodiazepine antagonist, flumazenil on modulation of the GABA(A) mediated chloride currents by allopregnanolone and on spontaneous synaptic activity in cultured hippocampal neurons using the patch-clamp technique. Allopregnanolone (0.03-0.3 microM), dose-dependently potentiated GABA-induced currents, an action significantly reduced by Ro15-4513 (10 microM). In contrast, flumazenil (10 microM) had no effect on the ability of allopregnanolone to potentiate GABA(A) currents but it blocked the effects of Ro15-4513. The frequency of spontaneous synaptic activity was significantly reduced in the presence of allopregnanolone (0.1 microM) from 1.5+/-0.7 to 0.1+/-0.04Hz. This action was partially reversed by Ro15-4513 (10 microM) but was not significantly influenced by flumazenil (10 microM). These findings suggest that the beneficial affects of Ro15-4513 in experimental HE result from attenuation of the effects of neurosteroids at GABA(A) receptors. Our results may provide a rational basis for the use of benzodiazepine inverse agonists in the management and treatment of hepatic encephalopathy in patients with liver failure.
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Affiliation(s)
- Samir Ahboucha
- Neuroscience Research Unit, CHUM-Hôpital Saint-Luc, 1058 St. Denis, Montreal, Quebec, Canada H2X 3J4
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Ahboucha S, Butterworth RF. Role of endogenous benzodiazepine ligands and their GABA-A--associated receptors in hepatic encephalopathy. Metab Brain Dis 2005; 20:425-37. [PMID: 16382352 DOI: 10.1007/s11011-005-7928-y] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Benzodiazepine receptor ligands are suggested to play a role in the pathogenesis of hepatic encephalopathy (HE). Accumulation of these ligands in brain was suggested to explain in part the notion of"increased GABAergic tone," the rational for which arose initially from reports of a beneficial effect of the selective benzodiazepine antagonist flumazenil in HE patients. It was suggested on the basis of the effect of flumazenil in human HE that liver failure may result in alterations of the density and/or affinity of the benzodiazepine-associated GABA-A receptor site. Subsequent controlled-clinical trials showed that fumazenil had a transient beneficial effect in only a subpopulation of HE patients. In contrast to the antagonists, partial inverse agonists of the benzodiazepine receptor have unequivocal beneficial effects on behavioral and electro-physiological performance in all experimental models of HE studied so far. Benzodiazepine-associated GABA-A receptors have consistently been demonstrated to be unaltered in both human and experimental HE. Contrary to initial reports, the so-called "endogenous benzodiazepines" do not appear to be significantly related to the pathogenesis of HE. On the other hand, nonbenzodiazepine GABA-A receptor complex modulators, such as neuro-steroids, recently identified in brain in human and experimental HE, may provide a new mechanistic basis for this disorder and lead to novel treatments for human HE.
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Affiliation(s)
- Samir Ahboucha
- Neuroscience Research Unit, CHUM-Hôpital Saint-Luc, Montreal, Quebec, Canada
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18
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Torisu S, Washizu M, Hasegawa D, Orima H. BRAIN MAGNETIC RESONANCE IMAGING CHARACTERISTICS IN DOGS AND CATS WITH CONGENITAL PORTOSYSTEMIC SHUNTS. Vet Radiol Ultrasound 2005; 46:447-51. [PMID: 16396258 DOI: 10.1111/j.1740-8261.2005.00082.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
Abstract
Animals with a portosystemic shunt (PSS) often have neurologic abnormalities. Diagnostic imaging, including brain magnetic resonance (MR) imaging, is not performed routinely in these animals. In this study, brain MR images were obtained in 13 dogs and three cats with a PSS, and in 15 dogs and five cats that were neurologically normal and used as controls. All animals with a PSS had widened sulci. In addition, 10 out of 13 dogs with a PSS and one out of three cats with a PSS had hyperintense focal areas in the lentiform nuclei on T1-weighted (T1W) images, which did not enhance after intravenous gadolinium. Following surgical correction of the PSS, MR imaging examinations were repeated in one dog and one cat. The hyperintensity of the lentiform nuclei had decreased. This study indicates that MR imaging findings of widened sulci and hyperintensity of the lentiform nuclei on T1W images may be found in dogs and cats with a PSS.
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Affiliation(s)
- Shidow Torisu
- Laboratory of Veterinary Medical Teaching Hospital, Nippon Veterinary and Animal Science University, 1-7-1, Kyonan-cho, Musasino-shi, Tokyo 180-8602, Japan.
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Melo VAD, Ceneviva R, Godoy ÁQD, Santos JED, Melo GBD. Alterações funcionais do fígado após derivação porto-cava e hepatectomia parcial: Estudo experimental em cães. Rev Col Bras Cir 2004. [DOI: 10.1590/s0100-69912004000100004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
OBJETIVO: Estudar os efeitos da derivação porto-cava sobre a função hepática de cães. MÉTODO: Vinte animais foram divididos em dois grupos: o Grupo I foi submetido à hepatectomia parcial de 28,7% e o Grupo II, à hepatectomia parcial associada à derivação porto-cava. Os parâmetros analisados foram: consumo de anestésico durante o ato cirúrgico, dosagem de amônia pré e pós-operatória (15° e 30° dia), AST, bilirrubina total e frações, proteínas totais, albumina e teste de retenção da bromosulfaleína (pré-operatório e 30° dia do pós-operatório) RESULTADOS: O consumo de anestésico foi significativamente menor no Grupo II. No Grupo I, apenas a AST estava elevada no pós-operatório quando comparada aos valores pré-operatórios. Já no Grupo II, a amonemia estava elevada no 15° e no 30° dia do pós-operatório em relação ao pré-operatório e aos mesmos períodos do Grupo I. Todos os outros parâmetros analisados apresentaram-se elevados quando comparados com os valores anteriores à cirurgia e aos do Grupo I, com exceção das proteínas totais e da albumina, que estavam significativamente reduzidas. CONCLUSÕES: A derivação porto-cava causa comprometimento importante da função hepática, traduzido por elevação da amônia sanguínea e alteração nas provas funcionais do fígado.
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Jones EA. Potential mechanisms of enhanced GABA-mediated inhibitory neurotransmission in liver failure. Neurochem Int 2003; 43:509-16. [PMID: 12742098 DOI: 10.1016/s0197-0186(03)00041-x] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Affiliation(s)
- E Anthony Jones
- Department of Gastrointestinal and Liver Diseases, Academic Medical Center, Meibergdreef 9, 1105 AZ Amsterdam-ZO, The Netherlands.
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Shimada Y, Kiyosawa M, Nariai T, Oda K, Toyama H, Ono K, Senda M, Ishiwata K. Quantitative in vivo measurement of central benzodiazepine receptors in the brain of cats by use of positron-emission tomography and [11C]flumazenil. Am J Vet Res 2003; 64:999-1002. [PMID: 12926592 DOI: 10.2460/ajvr.2003.64.999] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVE To map central benzodiazepine receptors (BZRs) in the brain of cats by use of positron-emission tomography (PET) and [11C]flumazenil. ANIMALS 6 male cats that weighed between 2.0 and 3.6 kg. PROCEDURE Brain images obtained by PET evaluation of [11C]flumazenil were superimposed on T2-weighted magnetic-resonance imaging (MRI) scans of the same cats. Detailed anatomic regions, such as the cerebral cortex, striatum, thalamus, midbrain, and cerebellum, on the PET images were evident by PET-MRI registration. Regional binding of [11C]flumazenil to BZRs was quantitatively measured by use of a model with 2 tissue compartments and 4 variables. RESULTS The highest value for distribution volume was observed in the cerebral cortex, and the lowest value was found in the midbrain of cats. CONCLUSIONS AND CLINICAL RELEVANCE Binding of [11C]flumazenil to BZRs in the brain of cats can be quantitatively measured by use of PET with the aid of PET-MRI registration. It is difficult to diagnose changes in these neuroreceptors within the field of current veterinary science. In the future, PET should prove useful for investigating and diagnosing brain disorders in animals in clinical settings.
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Affiliation(s)
- Yuhei Shimada
- Positron Medical Center, Tokyo Metropolitan Institute of Gerontology, 1-1 Naka-cho, Itabashi-ku, Tokyo 172-0022, Japan
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Melo VAD, Ceneviva R, Godoy ÁQD, Santos JED, Melo GBD. Alterações bioquímicas e morfológicas após anastomose porto-cava e hepatectomia parcial: estudo experimental em cães. Acta Cir Bras 2003. [DOI: 10.1590/s0102-86502003000300013] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
OBJETIVO: Estudar os efeitos da anastomose porto-cava sobre a morfologia e bioquímica do fígado de cães. MÉTODOS: Vinte animais foram divididos em 2 grupos: o Grupo I foi submetido à hepatectomia parcial de 28,7% e o Grupo II, à hepatectomia parcial associada à derivação porto-cava. Os parâmetros analisados foram: peso corpóreo, colesterol e triglicérides plasmáticos, lipídios e glicogênio hepáticos e índice ponderal de regeneração hepática. Os dados foram analisados no pré-operatório e no 30° dia do pós-operatório. RESULTADOS: No Grupo I, apenas os lipídios hepáticos estavam significativamente elevados 30 dias após a cirurgia. No Grupo II, o colesterol plasmático e o glicogênio hepático apresentaram redução no pós-operatório, enquanto os lipídios hepáticos estavam significativamente elevados. Comparando-se os 2 grupos, houve diferença estatisticamente significativa nos valores do colesterol plasmático, do glicogênio e do índice de regeneraçãohepática. CONCLUSÃO: A anastomose porto-cava causa prejuízos morfológicos e bioquímicos significativos ao fígado, além de redução significativa do peso corpóreo.
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