Effects of fasting on blood plasma levels, metabolism and metabolic effects of XXXX and @entity1063 in steers.

@entity4323 @entity1718 @entity1009 @entity1425 @entity4322 @entity3691 @entity1063 @entity413
Experiments were designed to study effects of 3 days of fasting on blood plasma levels, metabolic clearance rates (MCR) and effects of @entity1063 (NE) and @entity1425 (E) on levels of @entity413 , nonesterified @entity1718 ( @entity3691 ) and immunoreactive insulin (IRI) in 12 steers. During fasting, levels of E, NE and protein did not change, whereas IRI, T3 and @entity413 decreased and @entity3691 , @entity4323 and @entity4322 increased. Before and at the end of fasting, NE or E were iv infused for 120 min. NE and E were elevated after 15 min and to the end of the infusion. The increase in E, but not in NE, was significantly greater after 3 days of fasting than before fasting (P less than 0.05). MCR for E was lower after fasting (299 +/- 17 vs 204 +/- 10 ml.kg-0.75. @entity1009 ; P less than 0.001), whereas MCR for NE was not significantly different (455 +/- 37 vs 400 +/- 27 ml.kg-0.75. @entity1009 ). MCR was higher for NE than for E, both before and after fasting (P less than 0.05). After the infusion, E and NE decreased within minutes to pre-infusion concentrations. During E infusions, @entity3691 increased significantly more, whereas @entity413 increased less in fasted than in fed animals. During NE infusions, @entity3691 increased in fasted, but not in fed animals, and @entity413 increased less at the end than before fasting. IRI decreased during E infusions only in fed animals, and transiently increased after the infusion, except after NE infusion in fasted steers.(ABSTRACT TRUNCATED AT 250 WORDS)
