Cholecystokinin octapeptide increases passive avoidance latencies in rats.

Area of Science:

• Neuroscience
• Behavioral Pharmacology
• Memory Research

Background:

• The neuropeptide cholecystokinin (CCK) plays a role in various physiological processes, including learning and memory.
• CCK octapeptide (CCK-8) is a biologically active fragment of CCK that has been investigated for its effects on cognitive function.

Purpose of the Study:

• To investigate the effect of cholecystokinin octapeptide (CCK-8) on passive avoidance memory in rats.
• To determine if CCK-8 influences memory consolidation over time.

Main Methods:

• Rats underwent passive avoidance conditioning involving electrical footshock.
• Intraperitoneal injections of either 0.9% NaCl (control) or CCK-8 were administered.
• Passive avoidance behavior was assessed at 24 and 48 hours post-conditioning.

Main Results:

• No significant effect of CCK-8 on passive avoidance was observed at the 24-hour test.
• CCK-8 administration (100 and 200 micrograms/kg) significantly increased passive avoidance latencies at the 48-hour test.
• Control rats exhibited decreased latencies from 24 to 48 hours, a trend not seen in CCK-8 treated rats.

Conclusions:

• CCK-8 demonstrates a time-dependent effect on passive avoidance memory, enhancing long-term retention.
• These findings suggest CCK-8 may play a role in the consolidation of memories associated with aversive experiences.