Evaluation of Lateral Hypothalamic Area Catecholamine Levels Following Intravenous Glucose Administration by Microdialysis Method in Rats

Aim: We aimed to investigate the effects of intravenous glucose administration in the lateral hypothalamic
area (LHA) on the levels of noradrenaline, dopamine and their metabolites dihydroxyphenylglycol (DHPG)-
dihydroxyphenylaceticacid (DOPAC) by brain microdialysis method.
Patients and Methods: Adult male Wistar albino rats in 2 normally fed groups and 2 groups of restricted
food intake for 24 hours (saline and glucose administered) were used. Microdialysis procedures were
performed on the rats in LHA under anesthesia and samples were collected in 20 minutes. After the first
samples were recorded as control, 0.9% saline was administered to the control groups and 50% glucose
solution was administered intravenously to the glucose groups at a dose of 1.4 ml/kg. During the next 40
minutes, samples were collected and analyzed on the HPLC-ECD system. One-way ANOVA was used for
statistical evaluation.
Results: Noradrenaline concentration was higher in fasted rats than in satiated animals at baseline.
Noradrenaline levels at the 20th minute were significantly decreased in both fasted-satiated groups
compared to control group (p=0.01). There was no statistically significant difference in the 40th minute
noradrenaline values and dopamine-DHPG-DOP AC levels compared to control.
Conclusion: Systemic glucose administration decreased LHA noradrenaline concentration in fasted and
satiated rats. It can be mentioned that noradrenergic neurotransmission in LHA can be modulated by
plasma glucose.