Dopamine and hepatic oxygen supply – demand relationship

The present study examined the effect of small, vasodilating doses of dopamine on the hepatic oxygen supply – uptake ratio. Thirteen miniature pigs weighing 18–27 kg were studied under sodium pentobarbital anesthesia. Hepatic arterial and portal blood flows were measured. Oxygen content in arterial, portal, and hepatic venous blood was determined. Dopamine was infused in doses of 5, 10, and 15 μg∙kg−1∙min−1. Dopamine infusion was associated with a dose-related increase in hepatic oxygen uptake and a dose-independent increase in hepatic oxygen delivery with a maximal increase (30%) in the hepatic oxygen delivery at 10 μg∙kg−1∙min−1. The hepatic oxygen delivery–uptake ratio remained unchanged during dopamine infusion in doses of 5 and 10 μg∙kg−1∙min−1 and significantly decreased during the dose of 15 μg∙kg−1∙min−1. The study demonstrated that an increase in cardiac output and hepatic oxygen delivery during dopamine administration was not associated with an improvement in hepatic oxygen supply – demand relationship since hepatic oxygen uptake also increased.Key words: dopamine, hepatic blood flow, hepatic oxygenation. </jats:p

Airborne Lidar Measurements of the Two-Dimensional Atmospheric Pressure Profile

This paper describes the first high accuracy remote measurements of the two-dimensional atmospheric pressure field. Pressure is a fundamental atmospheric state variable that is required for virtually all atmospheric applications. The vertical and horizontal structure of the static pressure field characterizes the spatial distribution of mass in the atmosphere. Horizontal gradients of pressure represent the primary physical force leading to all scales of atmospheric circulations in the horizontal dimension which includes the large-scale general circulation as well as mesoscale phenomena such as sea/land breezes.</jats:p

Antihyperglycemic effects of baicalin on streptozotocin - nicotinamide induced diabetic rats

The aim of the study was to investigate the effects of baicalin on blood glucose, insulin and cytokine levels. Rat diabetes was induced by intraperitoneal (i.p.) injection of nicotinamide and streptozotocin. Diabetic rats were dosed with i.p. baicalin or oral metformin daily for 8 days. Blood glucose, insulin and hepatic glycogen were determined using conventional methods. The activity of hepatic hexokinase was determined using a coupled assay with glucose-6-phosphate dehydrogenase. Serum levels of interleukin-6 (IL-6), tumor necrosis factor-a (TNF-a) and adiponectin were measured by enzyme-linked immunosorbent assay. Administration of baicalin at 50 or 100 mg/kg signifi cantly decreased plasma glucose levels in a dose dependent manner. The serum insulin level was not increased by baicalin treatment. Administration of baicalin at a high dose (100 mg/kg) resulted in a signifi cant increase of liver glycogen content and a reduction of serum TNF-a. The activity of hepatic hexokinase was signifi cantly increased after dosing baicalin at 25, 50 or 10 mg/kg. Administration of baicalin (50 or 10 mg/kg) or metformin (10 mg/kg) signifi cantly alleviated the morphological injury to the pancreas caused by STZ. The possible mechanisms contributing to the hypoglycemic effect include increasing the hepatic glycogen content and glycolysis, and reducing the serum levels of TNF-a.No Full Tex