Platelet GABA-transaminase in affective illness

Area of Science:

• Neuroscience
• Biochemistry
• Psychiatry

Background:

• Gamma-aminobutyric acid (GABA) is a primary inhibitory neurotransmitter.
• Altered GABA metabolism is implicated in various affective disorders.
• Platelets offer a accessible model for studying certain enzyme activities.

Purpose of the Study:

• To investigate platelet GABA-transaminase activity in bipolar disorder patients.
• To explore potential genetic influences on enzyme activity.
• To examine the effect of feeding state on enzyme levels.

Main Methods:

• Platelet GABA-transaminase activity was measured.
• Study included bipolar patients, healthy volunteers, and monozygotic twins.
• Activity was compared between fasting and postprandial states.

Main Results:

• Mean platelet GABA-transaminase activity was significantly lower in bipolar patients compared to controls.
• Lower activity in female bipolar patients may contribute to the overall group difference.
• Enzyme activity showed significant correlation in monozygotic twins, indicating genetic influence.
• Postprandial enzyme activity was significantly lower than fasting activity.

Conclusions:

• Reduced platelet GABA-transaminase activity may be a biomarker for bipolar disorder.
• Genetic factors likely play a role in regulating platelet GABA-transaminase levels.
• GABA metabolism alterations are relevant to the pathophysiology of affective illness.