title: Acute effect of cholecystokinin on short-term synaptic plasticity in the rat hippocampus.
abstract: Cholecystokinin (CCK), a peptide hormone found in the gut, is the most abundant peptide neurotransmitters in the brain, and its acute effects on the brain activity have been shown. In this study we aimed to evaluate the acute effects of CCK on short-term synaptic plasticity in the dentate gyrus (DG) of the rat hippocampus. Via stereotaxic surgery, the stimulating and the recording electrodes were placed in the perforant pathway and dentate gyrus, respectively and 30 min after intraperitoneal (i.p.) injection of CCK octapeptide sulfated (CCK-8S, 1.6 μg/kg), evoked responses were recorded after delivering of paired-pulse stimulations at 10 to 500 ms inter-stimulus intervals. With respect to the control group that received saline instead of CCK, in baseline responses, slope of field excitatory postsynaptic potential (fEPSP) 5 min and 10 min after injection of CCK-8S (p<0.05) and population spikes (PS)- amplitudes 5 min after injection of CCK-8S (p<0.05) were significantly increased. In paired pulse responses, PS amplitudes were increased in the CCK group, but these enhancements only were significant at inter-stimulus interval 40 ms (p<0.05). However fEPSP slopes were decreased at inter-stimulus intervals 70 ms (p<0.05), 120 ms (p<0.01), 150 ms (p<0.001) and 300 ms (p<0.001). The results showed that CCK-8S has a transient excitatory effects on baseline responses, but it inhibits paired pulse indices in acute. Therefore, in a short period of time, effect of CCK on the function of synapses is time dependent, and it has stimulatory or inhibitory effects at different time periods.
authors: Applied Physiology Research Center, Isfahan University of Medical Sciences, Isfahan, I.R. Iran.
authors: L Kamali
authors: LK
authors: Dolatabadi
authors: Department of Physiology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, I.R. Iran ; Biosensor Research Center, Isfahan University of Medical Sciences, Isfahan, I.R. Iran.
authors: P
authors: P
authors: Reisi
keywords: Cholecystokinin; Dentate gyrus; Hippocampus; Paired pulse depression; Paired pulse facilitation; Rat
references: Neuropharmacology. 2008 Jan;54(1):117-28
references: 17689570
references: Peptides. 2001 Aug;22(8):1325-30
references: 11457528
references: Brain Res. 1988 Jun 7;451(1-2):309-18
references: 3251590
references: Neurosci Lett. 2013 Aug 9;549:34-9
references: 23827217
references: Pathophysiology. 2010 Feb;17(1):33-8
references: 19646849
references: Comp Biochem Physiol C Toxicol Pharmacol. 2001 Jan;128(1):11-7
references: 11166669
references: Nat Neurosci. 2007 Sep;10(9):1128-30
references: 17676058
references: J Neurochem. 1991 Mar;56(3):917-22
references: 1993898
references: Ann N Y Acad Sci. 1985;448:361-74
references: 2862830
references: Synapse. 1995 Oct;21(2):158-68
references: 8584977
references: J Comput Neurosci. 2010 Dec;29(3):509-19
references: 20177763
references: Psychopharmacology (Berl). 2009 Mar;202(4):559-67
references: 18836704
references: Brain Res. 2008 May 23;1211:30-6
references: 18433735
references: J Neurosci. 2010 Apr 14;30(15):5136-48
references: 20392936
references: Am J Physiol Regul Integr Comp Physiol. 2008 Mar;294(3):R803-10
references: 18160529
references: Physiol Behav. 2002 Feb 1-15;75(1-2):15-23
references: 11890948
references: Gen Pharmacol. 1998 Oct;31(4):637-41
references: 9792229
references: Hippocampus. 2011 Nov;21(11):1228-39
references: 20623762
references: Neuropharmacology. 1984 Nov;23(11):1305-9
references: 6098846