AIMTo study the effect of volume expansion by 0.9% and 1.8% sodium solution on cardiac-renal reflex activity and the role of cardiac-renal reflex in the regulation of integrated function.

METHODS18 health pentobarbital-anaesthetized rabbits were divided evenly into 2 groups at random, bilateral sino-aortic denervation, intubated via right jugular vein to monitor CVP, left renal nerve separated and ending sectioned to record ERSNA, bilateral ureter intubated to collect urine, right femoral intubated to get blood sample. 15% of whole body blood volume of 0.9% and 1.8% sodium solution were injected via jugular vein 10 ml per minute respectively. The CVP, ERSNA, bilateral urine volume and coefficient of sodium excretion were measured before treated, during treated, one minute, five minutes and ten minutes after treated.

RESULTSVolume expansion by 0.9% and 1.8% sodium solution respectively resulted in the increase of CVP by 64.00% +/- 15.56% and 77.00% +/- 23.74%; the decrease of the frequency of ERSNA by 44.00% +/- 13.64% and 63.00% +/- 12.49%, the average burst time of ERSNA by 37.00% +/- 16.49% and 31.00% +/- 10.69%, the increase of average interval of ERSNA bursts by 60.00% +/- 18.38% and 68.00% +/- 27.04%; the increase of urine volume by 158.00% +/- 28.10% and 640.00% +/- 155.39% in left kidney, 192.00% +/- 32.26% and 1343.00% +/- 429.95% in the right; the increase of coefficient of sodium excretion by 132.00% +/- 35.23% and 376.00% +/- 121.72% in the left, 300.00% +/- 76.99% and 856.00% +/- 261.48% in the right.

CONCLUSIONVolume expansion by different solution stimulate the receptors of cardiopulmonary and regulate the water and sodium excretion of the kidney by the cardiac-renal reflex to modulate the stabilization of blood volume.

Animals ; Blood Volume ; drug effects ; physiology ; Central Venous Pressure ; Heart ; drug effects ; innervation ; Kidney ; drug effects ; innervation ; Rabbits ; Reflex ; Saline Solution, Hypertonic ; pharmacology

Portal hypertension as a consequence of liver cirrhosis is responsible for serious complications such as variceal bleeding, ascites and hepatic encephalopathy. Successful pharmacological treatment of portal hypertension can prevent the risk of the variceal bleeding, and contribute to reduce the morbidity and mortality in patients with liver cirrhosis. To identify the effect of drugs on portal hypertension, portal pressure was evaluated accurately before and after the drug administration. The hepatic venous pressure gradient has been accepted as the gold-standard method for assessing the severity of portal hypertension and the response to drug treatment. The mean hepatic venous pressure gradient was 15.1+/-5.4 mmHg in Korean cirrhotic patients who had experienced variceal bleeding. Non-selective beta blockers are the treatment of choice for primary and secondary prevention of variceal bleeding. The dose of propranolol should be subsequently adjusted until the resting heart rate had been reduced by 25% or less than 55 beats per minute. It has been reported that the optimal dose of propranolol is variable due to racial differences in cardiovascular receptor sensitivity. In Korean patients with portal hypertension and liver cirrhosis, the mean required dose of propranolol to reach target heart rate was 165 mg (range; 80-280 mg). This review covers mainly the results of the pharmacological therapy of portal hypertension in Korean cirrhotic patients.
Adrenergic beta-Antagonists/administration & dosage ; Hepatic Veins ; Humans ; Hypertension, Portal/diagnosis/*drug therapy/physiopathology ; Korea ; Liver Cirrhosis/complications/physiopathology ; Propranolol/administration & dosage ; Venous Pressure/drug effects