Livers obtained from fed or fasted rats were perfused with blood from fasted rats with and without the addition of glucagon and/or a hyperlipemic serum (HLS).In addition to its well-known hyperglycemic effect, glucagon increased the blood levels of the ketone bodies and of urea, and decreased the levels of cholesterol, total lipids and NEFA.The magnitude of the effects noted were dependent upon the previous state of the liver and the addition of the hyperlipemic serum.In the fed liver, glucagon produced a greater degree of hyperglycemia than in the fasted liver and this effect was enhanced by the addition of a hyperlipemic serum. In fasted livers the addition of a hyperlipemic serum did not increase the hyperglycemia produced by glucagon alone.Total lipids, cholesterol and NEFA were decreased when glucagon was added to either the fasted or fed liver, in the presence or absence of a hyperlipemic serum.Glucagon caused a greater increase in the level of ketone bodies in the fasted than in the fed liver and this effect was increased by the addition of a serum rich in lipids.The addition of glucagon caused an increase in the levels of urea and this effect was reduced when a hyperlipemic scrum was acMted. DIABETES 15:74048, October, 1966. A survey of the available literature on the effects of glucagon on various aspects of lipid metabolism discloses unexplained discrepancies in the results. On the one hand it has been reported that glucagon is lipolytic and in the main inhibits the synthesis of fat and cholesterol. 5 ' 21 ' 22 ' 36 ' 43 ' 52 On the other hand there also exist data to show that glucagon lowers the concentration of fatty acids in the plasma and increases fat synthesis. 1 -14 ' 43 In the case of ketone body metabolism,

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A technic for in situ perfusion of rat pancreas alone or with a small intestine preparation, which is suitable for studying insulin and/or glucagon secretion and the role intestinal factor(s) has upon it, is described. Krebs- Ringer bicarbonate buffer, containing 4.0 per cent bovine albumin and 80 mg. per 100 ml. glucose with pH adjusted to 7.4, was used as perfusate. When the pancreas was perfused with a nonrecirculated buffer there was no significant change in the levels of glucose or insulin in the perfusate, while with recirculated buffer, there was a decrease in both measurements. When additional glucose was added to the perfusate, there was an increase of insulin levels, more marked in the pancreas perfusion with recirculated buffer (possibly pancreatic glucagon plus glucose effect) than in nonrecirculated ones (glucose effect). In pancreas-intestine perfusion with recirculated buffer, there was a decrease of the levels of insulin and glucose, and when additional glucose was added to the perfusate, there was an increase of the levels of insulin and glucose (possibly pancreatic glucagon and glucose effect). When glucose was passed through the intestine, there was a marked increase of the levels of insulin which was significantly higher than the previous group studied, probably due to the effects of glucose, pancreatic glucagon and intestinal factors. It may be possible by the results obtained to separate the effects of the three factors on the release of insulin: glucose, glucagon and intestinal factor(s).