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Zelek-Molik A, Costanzi M, Rafa-Zabłocka K, Kreiner G, Roman A, Vetulani J, Rossi-Arnaud C, Cestari V, Nalepa I. Fear memory-induced alterations in the mRNA expression of G proteins in the mouse brain and the impact of immediate posttraining treatment with morphine. Prog Neuropsychopharmacol Biol Psychiatry 2019; 93:221-231. [PMID: 30953677 DOI: 10.1016/j.pnpbp.2019.04.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/02/2019] [Revised: 03/27/2019] [Accepted: 04/02/2019] [Indexed: 10/27/2022]
Abstract
Disturbances in fear-evoked signal transduction in the hippocampus (HP), the nuclei of the amygdala (AMY), and the prefrontal cortex (PFC) underlie anxiety-related disorders. However, the molecular mechanisms underlying these effects remain elusive. Heterotrimeric G proteins (GPs) are divided into the following four families based on the intracellular activity of their alpha subunit (Gα): Gα(s) proteins stimulate cyclic AMP (cAMP) generation, Gα(i/o) proteins inhibit the cAMP pathway, Gα(q/11) proteins increase the intracellular Ca++ concentration and the inositol trisphosphate level, and Gα(12/13) proteins activate monomeric GP-Rho. In the present study, we assessed the effects of a fear memory procedure on the mRNA expression of the Gα subunits of all four GP families in the HP, AMY and PFC. C57BL/6 J mice were subjected to a fear conditioning (FC) procedure followed by a contextual or cued fear memory test (CTX-R and CS-R, respectively). Morphine (MOR, 1 mg/kg/ip) was injected immediately after FC to prevent the fear consolidation process. Real-time quantitative PCR was used to measure the mRNA expression levels of Gα subunits at 1 h after FC, 24 h after FC, and 1 h after the CTX-R or CS-R. In the HP, the mRNA levels of Gα(s), Gα(12) and Gα(11) were higher at 1 h after training. Gα(s) levels were slightly lower when consolidation was stabilized and after the CS-R. The mRNA levels of Gα(12) were increased at 1 h after FC, returned to control levels at 24 h after FC and increased again with the CTX-R. The increase in the Gα(11) level persisted at 24 h after FC and after CTX-R. In the AMY, no specific changes were induced by FC. In the PFC, CTX-R was accompanied by a decrease in Gα(i/o) mRNA levels; however, only Gα(i2) downregulation was prevented by MOR treatment. Hence, the FC-evoked changes in Gα mRNA expression were observed mainly in the HP and connected primarily to contextual learning. These results suggest that the activation of signaling pathways by Gα(s) and Gα(12) is required to begin the fear memory consolidation process in the HP, while signal transduction via Gα(11) is implicated in the maintenance of fear consolidation. In the PFC, the downregulation of Gα(i2) appears to be related to the contextual learning of fear.
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Affiliation(s)
- Agnieszka Zelek-Molik
- Institute of Pharmacology, Polish Academy of Sciences, Department of Brain Biochemistry, 31-343 Krakow, Smętna Street 12, Poland
| | - Marco Costanzi
- Free University Maria Ss. Assunta (LUMSA), Department of Human Sciences, Rome, Italy
| | - Katarzyna Rafa-Zabłocka
- Institute of Pharmacology, Polish Academy of Sciences, Department of Brain Biochemistry, 31-343 Krakow, Smętna Street 12, Poland
| | - Grzegorz Kreiner
- Institute of Pharmacology, Polish Academy of Sciences, Department of Brain Biochemistry, 31-343 Krakow, Smętna Street 12, Poland
| | - Adam Roman
- Institute of Pharmacology, Polish Academy of Sciences, Department of Brain Biochemistry, 31-343 Krakow, Smętna Street 12, Poland
| | - Jerzy Vetulani
- Institute of Pharmacology, Polish Academy of Sciences, Department of Brain Biochemistry, 31-343 Krakow, Smętna Street 12, Poland
| | | | - Vincenzo Cestari
- Sapienza University Rome, Department of Psychology, Rome, Italy.
| | - Irena Nalepa
- Institute of Pharmacology, Polish Academy of Sciences, Department of Brain Biochemistry, 31-343 Krakow, Smętna Street 12, Poland.
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Tian S, Han J, Huang R, Xia W, Sun J, Cai R, Dong X, Shen Y, Wang S. Association of Increased Serum ACE Activity with Logical Memory Ability in Type 2 Diabetic Patients with Mild Cognitive Impairment. Front Behav Neurosci 2016; 10:239. [PMID: 28066203 PMCID: PMC5179508 DOI: 10.3389/fnbeh.2016.00239] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2016] [Accepted: 12/08/2016] [Indexed: 12/21/2022] Open
Abstract
Background: Angiotensin-converting enzyme (ACE) is involved in the chronic complications of type 2 diabetes mellitus (T2DM) and Alzheimer's disease. This study aimed to assess the pathogenetic roles of ACE and the genetic predisposition of its insertion/deletion (I/D) polymorphism in mild cognitive impairment (MCI) among T2DM patients. Methods: A total of 210 T2DM patients were enrolled. Among these patients, 116 satisfied the MCI diagnostic criteria and 94 exhibited healthy cognition. The cognitive functions of the patients were extensively assessed. The serum level and activity of ACE were measured via enzyme-linked immunosorbent assay and ultraviolet spectrophotography. The single-nucleotide polymorphisms of I/D gene of ACE were analyzed. Results: The serum level and activity of ACE in diabetic MCI patients (p = 0.022 and p = 0.008, respectively) were both significantly higher than those in the healthy controls. A significant negative correlation was found between their ACE activity and logical memory test score (LMT) (p = 0.002). Multiple stepwise regression iterated the negative correlation between ACE activity and LMT score (p = 0.035). Although no significant difference was found in the genotype or allele distribution of ACE I/D polymorphism between the groups, the serum levels and activity of ACE were higher in the DD group than in the ID and II groups (p < 0.05). Conclusions: Serum ACE activity could better predict logical memory in T2DM patients than ACE level. Further investigations on a large population size are necessary to test whether the D-allele of the ACE gene polymorphism is susceptible to memory deterioration.
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Affiliation(s)
- Sai Tian
- Department of Endocrinology, Affiliated Zhongda Hospital of Southeast UniversityNanjing, China; Medical School of Southeast UniversityNanjing, China
| | - Jing Han
- Department of Endocrinology, Affiliated Zhongda Hospital of Southeast University Nanjing, China
| | - Rong Huang
- Department of Endocrinology, Affiliated Zhongda Hospital of Southeast University Nanjing, China
| | - Wenqing Xia
- Department of Endocrinology, Affiliated Zhongda Hospital of Southeast University Nanjing, China
| | - Jie Sun
- Department of Endocrinology, Affiliated Zhongda Hospital of Southeast University Nanjing, China
| | - Rongrong Cai
- Department of Endocrinology, Affiliated Zhongda Hospital of Southeast University Nanjing, China
| | - Xue Dong
- Department of Endocrinology, Affiliated Zhongda Hospital of Southeast University Nanjing, China
| | - Yanjue Shen
- Department of Endocrinology, Affiliated Zhongda Hospital of Southeast University Nanjing, China
| | - Shaohua Wang
- Department of Endocrinology, Affiliated Zhongda Hospital of Southeast University Nanjing, China
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Pharmacological induction of hemeoxygenase-1 activity attenuates intracerebroventricular streptozotocin induced neurocognitive deficit and oxidative stress in rats. Eur J Pharmacol 2016; 772:43-50. [DOI: 10.1016/j.ejphar.2015.12.037] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2015] [Revised: 12/17/2015] [Accepted: 12/18/2015] [Indexed: 12/26/2022]
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Santos D, Colle D, Moreira E, Peres K, Ribeiro R, dos Santos A, de Oliveira J, Hort M, de Bem A, Farina M. Probucol mitigates streptozotocin-induced cognitive and biochemical changes in mice. Neuroscience 2015; 284:590-600. [DOI: 10.1016/j.neuroscience.2014.10.019] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2014] [Revised: 10/06/2014] [Accepted: 10/09/2014] [Indexed: 10/24/2022]
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Effect of Licofelone—A Dual COX/5-LOX Inhibitor in Intracerebroventricular Streptozotocin-Induced Behavioral and Biochemical Abnormalities in Rats. J Mol Neurosci 2014; 55:749-59. [DOI: 10.1007/s12031-014-0414-4] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2014] [Accepted: 08/21/2014] [Indexed: 12/25/2022]
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Tota S, Kamat PK, Saxena G, Hanif K, Najmi AK, Nath C. Central angiotensin converting enzyme facilitates memory impairment in intracerebroventricular streptozotocin treated rats. Behav Brain Res 2012; 226:317-30. [DOI: 10.1016/j.bbr.2011.07.047] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2011] [Revised: 07/18/2011] [Accepted: 07/25/2011] [Indexed: 02/07/2023]
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SP600125, a competitive inhibitor of JNK attenuates streptozotocin induced neurocognitive deficit and oxidative stress in rats. Pharmacol Biochem Behav 2010; 96:386-94. [DOI: 10.1016/j.pbb.2010.06.010] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/13/2010] [Revised: 05/26/2010] [Accepted: 06/20/2010] [Indexed: 02/04/2023]
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Deshmukh R, Sharma V, Mehan S, Sharma N, Bedi KL. Amelioration of intracerebroventricular streptozotocin induced cognitive dysfunction and oxidative stress by vinpocetine -- a PDE1 inhibitor. Eur J Pharmacol 2009; 620:49-56. [PMID: 19699735 DOI: 10.1016/j.ejphar.2009.08.027] [Citation(s) in RCA: 130] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2009] [Revised: 07/24/2009] [Accepted: 08/12/2009] [Indexed: 01/06/2023]
Abstract
Enhancing cyclic nucleotides signaling by inhibition of phosphodiesterases (PDEs) is known to be beneficial in disorders associated with cognitive decline. The present study was designed to investigate the effect of vinpocetine (PDE1 inhibitor) on intracerebroventricular (i.c.v.) streptozotocin induced experimental sporadic dementia of Alzheimer's type. Infusion of streptozotocin impaired learning and memory, increased oxidative-nitritive stress and induced cholinergic hypofunction in rats. Chronic treatment with vinpocetine (5, 10 and 20 mg/kg i.p.) for 21 days following first i.c.v. streptozotocin infusion significantly improved learning and memory in Morris water maze and passive avoidance paradigms. Further, vinpocetine significantly reduced the oxidative-nitritive stress, as evidenced by decrease in malondialdehyde (MDA) and nitrite levels, and restored the reduced glutathione (GSH) levels. Significant increase in acetylcholinesterase activity and lactate dehydrogenase levels was observed in the present model indicating cholinergic hypofunction and increase in neuronal cell damage. Chronic treatment with vinpocetine also reduced significantly the increase in acetylcholinesterase activity and lactate dehydrogenase levels indicating restorative capacity of vinpocetine with respect to cholinergic functions and preventing the neuronal damage. The observed beneficial effects of vinpocetine on spatial memory may be due to its ability to favorably modulate cholinergic functions, prevent neuronal cell damage and possibly through its antioxidant mechanism also.
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Affiliation(s)
- Rahul Deshmukh
- Division of Neuropharmacology, Department of Pharmacology, ISF College of Pharmacy, Punjab, India.
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Candesartan improves memory decline in mice: involvement of AT1 receptors in memory deficit induced by intracerebral streptozotocin. Behav Brain Res 2008; 199:235-40. [PMID: 19103228 DOI: 10.1016/j.bbr.2008.11.044] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2008] [Revised: 11/21/2008] [Accepted: 11/27/2008] [Indexed: 11/20/2022]
Abstract
The Renin-angiotensin system, besides blood pressure regulation, affects learning and memory as evidenced by improvement of cognition in hypertensive patients being treated with AT1 receptor blockers like candesartan. The present study examined the influence of candesartan on memory impairment induced by intracerebral streptozotocin (IC STZ 0.5 mg/kg) in mice. Candesartan (0.05 mg/kg and 0.1 mg/kg, i.p.) was given for 14 days following IC STZ administration. The dose of 0.1 mg/kg significantly improved latency period in passive avoidance test. Further, treatment with 0.1 mg/kg candesartan for 14 days significantly improved spatial memory in mice in water maze test also. In another group, after memory impairment in mice following IC STZ administration, memory improving effect of a 7 days treatment with 0.1 mg/kg candesartan lasted only for 3 subsequent days in water maze task. IC STZ increased oxidative stress but pretreatment with 0.1 mg/kg candesartan decreased oxidative stress as indicated by a decrease in MDA and increase in GSH. Further, candesartan decreased free radicals as evidenced by flow cytometry. IC STZ affected cholinergic system also by increasing acetylcholine esterase activity that was restored by pretreatment with 0.1 mg/kg candesartan. Locomotor activity and serum glucose level remained unaffected by candesartan treatment. These results suggest that AT1 receptors play a facilitatory role in STZ induced memory deficit and corroborate number of human studies that AT1 receptor blockers can be used therapeutically against cognitive decline in hypertensive patients.
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Tarumi T, Mikami A, Shimada K, Kamei C. Participation of the Cholinergic System in Ameliorating Effect of Vasopressin Fragment by Group I Metabotropic Glutamate–Receptor Blockade. J Pharmacol Sci 2008; 108:335-40. [DOI: 10.1254/jphs.08146fp] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
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Mikami A, Masuoka T, Yasuda M, Yamamoto Y, Kamei C. Participation of cholinergic system in memory deficits induced by blockade of hippocampal mGlu1 receptors. Eur J Pharmacol 2007; 575:82-6. [PMID: 17678890 DOI: 10.1016/j.ejphar.2007.07.010] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2007] [Revised: 06/29/2007] [Accepted: 07/04/2007] [Indexed: 11/21/2022]
Abstract
We investigated the role of hippocampal group I metabotropic glutamate receptors (mGlu(1) receptors) in the retrieval process of spatial memory using 8-arm radial maze performance with 4 arms baited. In addition, the participation of the cholinergic system in memory deficits induced by mGlu(1) receptors antagonist was studied. Intrahippocampal injection of (R,S)-1-Aminoindan-1,5-dicarboxylic acid (AIDA), a mGlu(1) receptor antagonist, significantly increased total error, reference memory error and working memory error at a dose of 20 nmol/side. Donepezil (0.5 and 1.0 mg/kg, p.o.) showed an ameliorative effect on AIDA-induced memory deficits. Improvement by donepezil of AIDA-induced memory deficits was antagonized by scopolamine (5 nmol/side) but not by mecamylamine (200 nmol/side) at a dose that did not affect performance. These findings clearly indicate that hippocampal mGlu(1) receptors play an important role in the retrieval of spatial memory. Furthermore, we found that hippocampal mGlu(1) receptors were closely associated with muscarinic receptors in memory performance.
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Affiliation(s)
- Azusa Mikami
- Department of Medicinal Pharmacology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan
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Huang CC, Hsu KS. Local protein synthesis and GABAB receptors regulate the reversibility of long-term potentiation at murine hippocampal mossy fibre-CA3 synapses. J Physiol 2004; 561:91-108. [PMID: 15345751 PMCID: PMC1665341 DOI: 10.1113/jphysiol.2004.072546] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Reversal of long-term potentiation (LTP) by long trains of low-frequency stimulation is generally referred to as depotentiation. One of the intriguing aspects of depotentiation is that the magnitude of depotentiation is inversely proportional to the time lag of depotentiation stimulation following LTP induction. Although the mechanisms underlying depotentiation have been widely explored, the factors that regulate the susceptibility of LTP to depotentiation stimulation remain largely unclear. We now report that multiple trains of high-frequency stimulation provide immediate synaptic resistance to depotentiation stimulation at the mossy fibre-CA3 synapses. The synaptic resistance to depotentiation stimulation depends on the amount of synaptic stimulation used to induce LTP; it is prevented by protein synthesis inhibitors and is input specific. In contrast, neither the transection of mossy fibre axons near granule cell somata nor the application of RNA synthesis inhibitors influences synaptic resistance to depotentiation stimulation. We also provide evidence that the induction of depotentiation is regulated by GABA(B) receptors. Application of a GABA(B) receptor antagonist significantly promoted the synaptic resistance to depotentiation stimulation, whereas inhibition of GABA transport delayed the onset of this synaptic resistance. These results suggest that local protein synthesis is required for the development of synaptic resistance to depotentiation stimulation, whereas the activation of GABA(B) receptors promotes the susceptibility to depotentiation stimulation. These two factors may crucially regulate the reversal and stability of long-term information storage.
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Affiliation(s)
- Chiung-Chun Huang
- Department of Pharmacology, College of Medicine, National Cheng Kung University, No. 1, Ta-Hsiue Road, Tainan 701, Taiwan
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Summers MJ, Crowe SF, Ng KT. Memory retrieval in the day-old chick: a psychobiological approach. Neurosci Biobehav Rev 2003; 27:219-31. [PMID: 12788334 DOI: 10.1016/s0149-7634(03)00032-0] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
This review integrates a series of studies conducted examining memory retrieval processes in the day-old chick. On the basis of these studies it is proposed that two processes are activated following retrieval of a memory. The first is an immediate memory recall or retrieval mechanism responsible for the chick's ability to remember the information and respond appropriately to the stimulus. The second process is activated following the completion of the first immediate retrieval phase. Further, it is proposed that the function of this secondary phase may be to allow for the modification of a memory undergoing storage processes. It is proposed that the processes of memory formation and memory retrieval are parallel at a cellular level, but at the functional level of information transfer they are interdependent.
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Affiliation(s)
- Mathew J Summers
- School of Psychology, University of Tasmania, Locked Bag 1342, 7250, Launceston, Tasmania, Australia.
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Abstract
The phenomenon of dissociated memory retrieval is observed when some influences (for example, pharmacological) on the brain result in specific changes of long-term memory. The purpose of present paper is to reveal possibilities of the phenomenon for study of long-term memory retrieval. Pharmacologically-induced dissociated states could be identified when the retrieval of responses learned before treatment is temporarily blocked by the drug influence, but the ability of the animals to learn new tasks is intact. Furthermore, memory traces that were formed in drugged state are not accessible for the retrieval in normal state and only the same drug treatment allows retrieving them. In the present work, dissociated learning of food-motivated tasks was carried out in Wistar rats with cholinesterase inhibitor physostigmine (0.5 mg/kg, intraperitonealy) or general anaesthetic sodium pentobarbital (15 mg/kg, intraperitonealy.). The retrieval of dissociated responses was studied under the influence of various doses of the same drugs. The results revealed the asymmetry of memory dissociation with physostigmine in contrast to pentobarbital-induced memory dissociation. Gradual access for the retrieval of dissociated memory traces after pharmacological modulation of cholinergic and GABA-ergic brain systems was shown. It was suggested an important role of hippocampus in memory dissociation, as a structure-performing match-mismatch operations between different retrieved memory traces.
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Affiliation(s)
- V I Arkhipov
- Institute of Theoretical and Experimental Biophysics, Pushchino, Moscow Region, Russia.
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Popik P, Bobula B, Janusz M, Lisowski J, Vetulani J. Colostrinin, a polypeptide isolated from early milk, facilitates learning and memory in rats. Pharmacol Biochem Behav 1999; 64:183-9. [PMID: 10495015 DOI: 10.1016/s0091-3057(99)00101-x] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
Initial observations in humans indicated that colostrinin, a complex of polypeptides derived from the colostrum of sheep, facilitates cognitive functioning in patients with Alzheimer's disease. Its effect on learning and memory in more controlled settings as well as the specificity of these effects were, however, unknown. The present experiments evaluated the effects of colostrinin on spatial learning (Morris water maze) and incidental memory (habituation test) in male Wistar rats of two age groups. Colostrinin, at a dose of 4 microg/rat IP, facilitated acquisition of spatial learning of 13- (aged) but not 3-month-old (young) rats. At the same dose, it improved incidental learning in aged rats, while the dose of 20 microg/rat attenuated it. Colostrinin did not change locomotor activity of rats. Taken together, the present findings indicate that colostrinin may have some beneficial effects on cognitive functioning, particularly in aged subjects. Given the fact that colostrum is the first nutritive agent of neonates, it might be speculated that its peptides may facilitate the early postnatal development of the cerebral neurons and their plasticity.
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Affiliation(s)
- P Popik
- Institute of Pharmacology, Polish Academy of Sciences, Kraków.
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Summers MJ, Crowe SF, Ng KT. Administration of DL-2-amino-5-phosphonovaleric acid (AP5) induces transient inhibition of reminder-activated memory retrieval in day-old chicks. BRAIN RESEARCH. COGNITIVE BRAIN RESEARCH 1997; 5:311-21. [PMID: 9197518 DOI: 10.1016/s0926-6410(97)00007-4] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
DL-2-Amino-5-phosphonovaleric acid (50 microM) administered immediately after a visual reminder presented to day-old chickens between 7.5 min and 24 h following a single trial passive avoidance learning task produced transient losses of memory on retention test, an effect not observed in the absence of a reminder or when the reminder was given 48 h post learning. The duration of the transient deficits decreased with increasing interval between training and the reminder trial. The time of onset of memory loss after the reminder trial appeared to increase with increasing interval between the training and the reminder trials. The results suggest that, for a period of at least up to 24 h after passive avoidance training, retrieval of memory may lead to processes which are sensitive to inhibition by the NMDA receptor antagonist AP5, with the duration of sensitivity post retrieval decreasing as the period of memory consolidation increases. The results extend previously reported findings and suggest the possibility that consolidation of a stable memorial representation of a learning experience may take over several days and may entail the concurrent laying down of a stable retrieval mechanism.
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Affiliation(s)
- M J Summers
- Department of Psychology, Monash University, Clayton, Victoria, Australia
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