Product Inhibition and Dose‐Dependent Bioavailability of Propranolol in the Isolated Perfused Rat Liver Preparation

1994 ◽  
Vol 83 (7) ◽  
pp. 931-936 ◽  
Author(s):  
Hany Ghabrial ◽  
Romina Nand ◽  
Cheryl K. Stead ◽  
Richard A. Smallwood ◽  
Denis J. Morgan
Keyword(s):  
Rat Liver ◽  
Product Inhibition ◽  
Isolated Perfused Rat Liver ◽  
Perfused Rat Liver ◽  
Liver Preparation ◽  
Dose Dependent

scholarly journals Benzoate stimulates glutamate release from perfused rat liver

1989 ◽  
Vol 264 (3) ◽  
pp. 837-843 ◽  
Author(s):  
D Häussinger ◽  
T Stehle ◽  
J P Colombo
Keyword(s):  
Rat Liver ◽  
Glutamate Release ◽  
Isolated Perfused Rat Liver ◽  
Perfused Rat Liver ◽  
Ammonia Metabolism ◽  
Ammonia Uptake ◽  
Glutamine Synthesis ◽  
Methionine Sulphoximine ◽  
Dose Dependent ◽  
Glutamate Efflux

In isolated perfused rat liver, benzoate addition to the influent perfusate led to a dose-dependent, rapid and reversible stimulation of glutamate output from the liver. This was accompanied by a decrease in glutamate and 2-oxoglutarate tissue levels and a net K+ release from the liver; withdrawal of benzoate was followed by re-uptake of K+. Benzoate-induced glutamate efflux from the liver was not dependent on the concentration (0-1 mM) of ammonia (NH3 + NH4+) in the influent perfusate, but was significantly increased after inhibition of glutamine synthetase by methionine sulphoximine or during the metabolism of added glutamine (5 mM). Maximal rates of benzoate-stimulated glutamate efflux were 0.8-0.9 mumol/min per g, and the effect of benzoate was half-maximal (K0.5) at 0.8 mM. Similar Vmax. values of glutamate efflux were obtained with 4-methyl-2-oxopentanoate, ketomethionine (4-methylthio-2-oxobutyrate) and phenylpyruvate; their respective K0.5 values were 1.2 mM, 3.0 mM and 3.8 mM. Benzoate decreased hepatic net ammonia uptake and synthesis of both urea and glutamine from added NH4Cl. Accordingly, the benzoate-induced shift of detoxication from urea and glutamine synthesis to glutamate formation and release was accompanied by a decreased hepatic ammonia uptake. The data show that benzoate exerts profound effects on hepatic glutamate and ammonia metabolism, providing a new insight into benzoate action in the treatment of hyperammonaemic syndromes.

The isolated perfused rat liver: Preparation and application

1987 ◽  
Vol 167 (1) ◽  
pp. 1-14 ◽  
Author(s):  
Allan W. Wolkoff ◽  
Kirsten L. Johansen ◽  
Tobias Goeser
Keyword(s):  
Rat Liver ◽  
Isolated Perfused Rat Liver ◽  
Perfused Rat Liver ◽  
Liver Preparation

Dose-dependent effects of acute lindane treatment on Kupffer cell function assessed in the isolated perfused rat liver

Xenobiotica ◽  
1997 ◽  
Vol 27 (7) ◽  
pp. 747-757 ◽  
Author(s):  
L. A. VIDELA* ◽  
P. TRONCOSO ◽  
A. C. M. ARISI ◽  
V. B. C. JUNQUEIRA
Keyword(s):  
Rat Liver ◽  
Kupffer Cell ◽  
Cell Function ◽  
Isolated Perfused Rat Liver ◽  
Perfused Rat Liver ◽  
Dose Dependent
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