Stiliana Belcheva | PubMed Health

PubMed2004

Differential effects of somatostatin on exploratory behavior after unilateral injections in to rat neostriatum.

The effects of somatostatin (SRIF) microinjected unilaterally (left or right) at a dose of 10, 50, and 100 ng into the neostriatum of male Wistar rats on exploratory behavior were studied. Unilateral injections of SRIF suppressed dose-related the exploratory activity as decreased the number of horizontal and vertical movements compared to the respective controls. The effect was more pronounced when SRIF was microinjected into the right neostriatum as compared to the left neostriatum. These findings suggest some asymmetric effects of SRIF, depending on the dose and the microinjected hemisphere.

Animals↗

PubMed2003

Cholecystokinin and learning and memory processes.

Cholecystokinin (CCK) is a classical brain-gut peptide that exerts a variety of physiological actions in the gastrointestinal tract and central nervous system. CCK occurs in several molecular forms of varying aminoacid length, the sulphated octapeptide (CCK-8) being the predominant form in the brain. CCK mediates its effects through interaction with specific receptors subdivided in two subtypes--CCK-A (present in the periphery and in few selected brain nuclei) and CCK-B (the predominant receptor subtype in the brain). CCK is implicated in variety of behavioral functions as satiety, anxiety, exploratory and locomotor activity and learning and memory. After a brief description of the distribution, molecular forms, release, inactivation, etc. of CCK in the brain, the present review summarizes the recent data on the role of CCK in learning and memory. The memory-enhancing effects of CCK have been demonstrated in various types of memory. Data showing that CCK-A receptors mediate mnemonic while CCK-B receptors mediate amnestic effects are also presented.

Animals↗