Transhepatic hormone levels in the portacaval shunted pig--the effects of arginine upon gastrin and glucagon release.

Hypergastrinemia and hyperglucagonemia follow portacaval shunt (PCS) or cirrhosis in man and experimental animals. The cause is unknown although portal diversion and hepatic dysfunction are suggested. In these studies transhepatic techniques were used to define the hepatic handling of basal and arginine-stimulated gastrin and glucagon levels in sham-operated and portacaval-shunted pigs and in a group of pair-fed sham-operated pigs. After PCS, basal gastrin levels were lower than those in sham-operated animals but were also lower in the pair-fed group, suggesting that the change resulted from partial starvation. Arginine-stimulation caused a rise in hepatic venous levels in PCS and in pair-fed pigs and in portal venous levels in sham-operated pigs. These data also suggested a response to diminished intake in PCS pigs. There was an immediate transitory rise in portal immunoreactive glucagon (Unger 30K) after PCS and a subsequent rise from the 4th postoperative day in all circulations. Arginine stimulation caused in sham-operated and PCS pigs a biphasic rise in the portal circulation and a later rise in the arterial circulation in PCS pigs. These data suggest that the effect of PCS upon gastrin levels is associated with the impaired appetite while the effect upon glucagon is the result of diversion past the liver.