Cerebral glucose uptake in lindane-treated rats

Area of Science:

• Neuroscience
• Toxicology
• Biochemistry

Background:

• Lindane (gamma-hexachlorocyclohexane) is a pesticide and ectoparasiticide known to stimulate the central nervous system (CNS) in mammals.
• Lindane exposure can induce convulsions and other signs of hyperexcitability, suggesting significant neurotoxic potential.
• Understanding the impact of lindane on brain function, specifically glucose metabolism, is crucial for assessing its neurological risks.

Purpose of the Study:

• To investigate the effects of lindane on regional brain glucose uptake in rats.
• To differentiate the impact of convulsant versus non-convulsant doses of lindane on brain glucose metabolism.
• To examine the effects of sub-chronic lindane exposure on brain glucose uptake patterns.

Main Methods:

• Male Wistar rats were treated with lindane at convulsant (150 mg/kg) and non-convulsant (30 mg/kg) doses, as well as a sub-chronic regimen (10 mg/kg/day for 1 week).
• Regional brain glucose uptake was measured using a modified 2-deoxyglucose (2-DG) method with [3H]2-DG.
• Radioactivity, indicating glucose uptake, was quantified in 18 dissected brain regions via liquid scintillation counting.

Main Results:

• A single convulsant dose of lindane significantly increased 2-DG uptake in the olfactory tubercles, hypothalamus, hippocampus, parafloculi, and hypophysis.
• Conversely, the convulsant dose decreased 2-DG uptake in the parietal cortex, thalamus, and pons-medulla.
• Non-convulsant doses and sub-chronic exposure showed less pronounced or different regional changes in glucose uptake, with increased uptake in superior colliculi and decreased uptake in the parietal cortex after sub-chronic treatment.

Conclusions:

• Lindane significantly alters regional brain glucose uptake, with distinct patterns observed at convulsant versus non-convulsant or sub-chronic exposure levels.
• The observed increase in 2-DG uptake in limbic regions at convulsant doses aligns with known lindane-induced neurotoxicity and limbic system involvement.
• These findings provide insights into the neurochemical mechanisms underlying lindane's CNS stimulant and convulsant effects.