Myocardial phospholipid metabolism in alloxan diabetic rats

Alloxan diabetes in rats was found to decrease the level of phospholipids in the heart. Measurement of specific phosphatides showed that the decrease was restricted only to phosphatidylethanolamine and lysophosphatidylcholine. Study of $\text{in}$$\text{vivo}$ incorporation of ³²Pi indicated an impairment of phosphatidylethanolamine synthesis and conversion of phosphatidylcholine into lysophosphatidyl choline in the heart of diabetic rats. Treatment of diabetic rats with insulin restored the levels of phosphatidylethanolamine and lysophosphatidylcholine and incorporation of ³²Pi into these phosphatides to almost normal.     

Vagal control of heart period in alloxan diabetic rats

Autonomic neuropathies are a frequent complication to diabetes in humans. Similar neuropathies have not been well-documented in animal models. To determine if diabetic rats would develop parasympathetic neuropathies, rats were made diabetic by the injection of alloxan into the tail vein and then maintained on daily injections of insulin. At various times subsequent to the induction of diabetes (3–5 weeks, 7–9 weeks, and 14 weeks), the effect of constant frequencies of vagal stimulation on the efferent cardiac chronotropic response was evaluated using analysis of variance techniques. It was found that the vagal parasympathetic effect was accentuated in diabetic rats. That is, at a given frequency of supramaximal vagal stimulation, the heart rate slowed more in diabetic rats than in nondiabetic rats. Whether a similar phenomenon exists in humans is not known.     

Effect of betacarotene on protein glycosylation in alloxan induced diabetic rats

Free radicals are increasingly formed in diabetes mellitus by the auto oxidation of glucose and glycosylated proteins. Oxidative stress and proteinglycosylation are closely related processes and have been shown to contribute to the development of complications in diabetes mellitus. The extent of protein glycosylation was assessed in alloxan induced diabetic rats after being treated with 50 mg of betacarotene for 40 days. The level of fructosamine and glycosylated haemoglobin was comparison with non treated diabetic rats. The results indicate the beneficial role of betacarotene in reducing diabetic complications like glycosylation in experimental diabetic rats.