Methamphetamine- and 3,4-methylenedioxymethamphetamine-induced behavioral changes in histamine H3-receptor knockout...

Area of Science:

• Neuroscience
• Pharmacology
• Genetics

Background:

• Histamine H(3) receptors modulate neurotransmitter release, including dopamine.
• Histaminergic neurons are known to influence behavioral responses to psychostimulants.

Purpose of the Study:

• To investigate the role of histamine H(3) receptors in psychostimulant-induced behavioral sensitization and reward.
• To compare the effects of methamphetamine and MDMA in histamine H(3) receptor-gene knockout (H3KO) mice and wild-type (WT) counterparts.

Main Methods:

• Assessment of locomotor activity, conditioned place preference (CPP), and c-Fos expression.
• Utilized H3KO mice and WT mice treated with methamphetamine (METH) and 3,4-methylenedioxymethamphetamine (MDMA).

Main Results:

• H3KO mice exhibited lower METH/MDMA-induced locomotion compared to WT mice.
• Locomotor sensitization to METH/MDMA occurred in both H3KO and WT mice.
• No significant differences in CPP were observed between H3KO and WT mice.
• METH treatment reduced c-Fos expression in the caudate-putamen of H3KO mice compared to WT mice, but not in the nucleus accumbens.

Conclusions:

• Histamine H(3) receptor deficiency may inhibit psychostimulant-induced increases in locomotion.
• The reward pathways associated with psychostimulants appear less affected by histamine H(3) receptor deficiency.