Response of One‐Humped Camel (Camelus dromedarius) to Intravenous Glucagon Injection and to Infusion of Glucose and Volatile Fatty Acids, and the Kinetics of Glucagon Disappearance from the Blood

Abstract

The effects of glucagon injection and infusion of glucose and volatile fatty acids were studied in onehumped camels. Twenty adult male camels were divided into four equal groups. The first group was infused with physiological saline and served as a control. The second group was injected with a single dose of glucagon, the third group was infused with glucose (50 %) in sterile saline, and the fourth group was infused with a volatile fatty acid (VFA) mixture. In the first, third and fourth groups, sampling was performed before the beginning of infusions (control time), and at 15, 30, 60 and 120 min post-infusion. Plasma glucagon concentrations were monitored in the second group at 5, 10, 15, 20, 30, 45, 90, 105 and 120 min after injection. For glucagon injection, glucose concentration peaked at 15 min post-injection, and tended to decrease thereafter. Plasma glucose concentrations showed significant rises above the basal value at all times after glucose infusion. VFA infusion had no apparent effect on plasma glucose concentration. After injection of glucagon, the plasma lactate concentration dropped significantly at 15 and 30 min, then increased gradually until it reached the original concentration of lactate at 120 min. However, glucose infusion elevated the plasma lactate concentration only at the end of the infusion period. A decrease in plasma lactate was observed at 60 min after VFA infusion. The present investigation provides evidence that the glucagon level in camels is higher than that in other ruminants and in man, and suggests that this is a probable species specificity, which would explain the higher level of glucose in the blood of camels than in that of other ruminants. The disappearance curve of injected glucagon had, as in other ruminants, an exponential two-compartment function. The hormone was rapidly distributed and was eliminated with a high rate of clearance.

Proteomics of old world camelid (Camelus dromedarius): Better understanding the interplay between homeostasis and desert environment

“… [31] . Moreover, the higher level of glucagon in camel with consequent elevated basal blood glucose [2] is consistent with the proposed role of vimentin in GLUT-induced adipocyte glucose transport [32] . These data suggest a possible modulating role of adipocyte vimentin for the tolerance of high blood glucose levels in camel.…”

“…The camel shows a true rumination pattern of digestion, expected for a ruminating ungulates; however, based on anatomical and physiological issues, it is considered as pseudo-ruminant. The camel also has the highest blood glucose level among all ruminants with similarly high glucagon levels [2] .…”

Dromedary glycosaminoglycans: Molecular characterization of camel lung and liver heparan sulfate

“…The high percentage of intermediate and undersulfated disaccharides and low percentage of unsulfated or highly sulfated disaccharides in camel liver HS makes it fall between porcine liver HS and human liver HS in its degree of sulfation. The unusual sulfation pattern of camel liver HS is most likely related to its biosynthesis and may be responsible for differences in liver function in the camel (Abdel-Fattah et al, 1999). Camel lung HS also shows an interesting disaccharide analysis, intermediate between porcine intestinal heparin and the heparan sulfates examined (Table 1).…”

Sequencing, Analysis, and Annotation of Expressed Sequence Tags for Camelus dromedarius

“…Camels are exceptional with regard to their carbohydrate metabolism. On the one hand, plasma glucose levels in camels are in the range or of those of monogastrics or even higher [11], although camels ferment carbohydrates to short-chain fatty acids on the same scale as sheep and lactating cows [12] and like ruminants, they also meet their glucose demands by endogenous gluconeogenesis [13]. On the other hand, the whole body insulin sensitivity of camels is even lower than that of adult ruminants [14].…”