The role of the neuropeptide galanin in forming type-specific behavioral characteristics.

State Research Institute of Experimental Medicine, Russian Academy of Medical Sciences, 12 Academician Pavlov Street, 197376, St. Petersburg, Russia.
Neuroscience and Behavioral Physiology 02/2008; 38(1):93-8. DOI: 10.1007/s11055-008-0013-3
Source: PubMed

ABSTRACT Intranasal administration of a galanin receptor blocker to rats was found to change their behavioral type on being placed in an unfamiliar environment, with decreases in movement and investigative activity and increases in the level of anxiety in the open field test. The basal level of expression of the galanin precursor mRNA in the anterior hypothalamus was significantly higher in rats with the active type of behavior in the open field test. In conditions of galanin receptor blockade, there was also a faster increase in the serum corticosterone level in response to a stress situation (forced swimming test), which was accompanied by a reduction in the immobilization time. These data support the involvement of galanin in the formation of individual-typological behavioral characteristics and demonstrate its important role in adaptation to stress.

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