Cholecystokinin effects on feeding, glucose, and pancreatic hormones in rhesus monkeys

The effects of cholecystokinin on feeding, and on plasma glucose and pancreatic hormone responses to a mixed-meal were determined in lean rhesus monkeys. Following an overnight fast the octapeptide of cholecystokinin (CCK-8) was administered intravenously over a 6 minute period coincident with the initiation of free feeding or an intragastric infusion of a mixed liquid diet. CCK-8 inhibited feeding and delayed the plasma glucose and insulin response to a mixed-meal. The threshold for the feeding effect ranged from 30 to 120 ng/kg/min across monkeys and did not extend beyond 15 minutes of the start of the CCK infusion. The delays in plasma glucose and insulin were not dependent on rate or amount of food entering the stomach. Further, there were no alterations from basal levels in plasma glucose or insulin prior to the onset of CCK-induced feeding inhibition. There was no evidence that CCK-8 stimulated insulin release, nor was the usual close relationship between plasma glucose and insulin levels in response to a mixed-meal changed by CCK-8.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/25259/1/0000702.pd

Effects of chronic exercise conditioning on thermal responses to lipopolysaccharide and turpentine abscess in female rats

Chronic exercise conditioning has been shown to alter basal thermoregulatory processes as well as the response to inflammatory agents. Two such agents, lipopolysaccharide (LPS) and turpentine (TPT) are inducers of fever in rats. LPS, given intraperitoneally (i.p.), involves a systemic inflammatory response whereas TPT given intramuscularly (i.m.) elicits a localized inflammation. We assessed if chronic exercise training in the rat would alter the thermoregulatory response to LPS and TPT. Core temperature ( T c ) and motor activity were monitored by radiotelemetry. Female Sprague Dawley rats were divided into two groups (trained and sedentary) and housed at an ambient temperature of 22°C. Animals voluntarily trained on running wheels for 8 weeks. In the first study, trained and sedentary female rats were injected i.p. with LPS (50 μg/kg) or an equal volume of 0.9% normal saline. In another study, trained and sedentary female rats were injected i.m. with TPT (10 μl)/rat or an equal volume of 0.9% normal saline. The time course of the LPS fever was very short compared to TPT. TPT injected animals displayed a smaller but more prolonged fever compared to LPS; however, training accentuated the febrile response to LPS (Δ T c =0.6°C in sedentary and 1.2°C in trained). Training had a slight suppression on TPT-induced fever during the daytime but had no effect on motor activity or nighttime T c . In contrast, exercise training led to a marked increase in the pyrogenic effects of LPS. We conclude that the effect of exercise training and source of infection (i.e., systemic versus localized in muscle) on fever is directly linked to type of pyrogenic agent.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/46159/1/204_2005_Article_36.pd

Impact of Optimized Breastfeeding on the Costs of Necrotizing Enterocolitis in Extremely Low Birthweight Infants

To estimate risk of NEC for ELBW infants as a function of preterm formula and maternal milk (MM) intake and calculate the impact of suboptimal feeding on NEC incidence and costs