- Home
- Knowledge Base
- References
Molsidomine modulates the cNOS activity in an experimental model of cholinergic damage induced by 192-IgG saporin.
Hernandez-Melesio MA, Gonzalez-Esquivel D, Ortiz-Plata A, Sanchez-Mendoza A, Sanchez-Garcia A, Alcaraz-Zubeldia M, Rios C, Perez-Severiano F (2011) Molsidomine modulates the cNOS activity in an experimental model of cholinergic damage induced by 192-IgG saporin. Neurosci Lett 491(2):133-137. doi: 10.1016/j.neulet.2011.01.023
Summary: Nitric oxide (NO) is required for the survival of cholinergic neurons in the basal forebrain. Delivery of nerve growth factor (NGF) is related to the modulation of NO – as excessive NO can lead to excitotoxicity. The authors administered molsidomine to rats that had previously received 220 ng of 192-IgG-SAP (Cat. #IT-01) into the medial septum. Molsidomine is a NO donator, and produced a significant recovery of NO activity in lesioned animals, indicating a potential therapeutic pathway.
Related Products: 192-IgG-SAP (Cat. #IT-01)
Gene regulation in the rat prefrontal cortex after learning with or without cholinergic insult.
Paban V, Chambon C, Farioli F, Alescio-Lautier B (2011) Gene regulation in the rat prefrontal cortex after learning with or without cholinergic insult. Neurobiol Learn Mem 95(4):441-452. doi: 10.1016/j.nlm.2011.02.005
Summary: Microarray technology was used to screen gene expression in a model of attention and memory deficit. Rats received bilateral injections of 192-IgG-SAP (Cat. #IT-01) into the medial septum and nucleus basalis magnocellularis (37.5 ng per side and 75 ng per side respectively). Gene expression in memory loss following the lesion was defined by one cluster related to cytoskeleton organization and proliferation, and glial and vascular remodeling. These are processes associated with brain repair after injury.
Related Products: 192-IgG-SAP (Cat. #IT-01)
The effects of neonatal forebrain cholinergic lesion on adult hippocampal neurogenesis.
Rennie K, Frechette M, Pappas BA (2011) The effects of neonatal forebrain cholinergic lesion on adult hippocampal neurogenesis. Brain Res 1373(10):79-90. doi: 10.1016/j.brainres.2010.11.091
Summary: Intraventricular injections of 192-IgG-SAP (Cat. #IT-01) have been shown to reduce the number of cells expressing a marker for immature neuroblasts in the dentate gyrus, as well as possibly impairing the response to environmental enrichment. This study looked to expand on those observations. 300 ng of 192-IgG-SAP was infused into each ventricle of post-natal day 7 rats. The data suggest that the lesion accelerates the death of newborn cells, but does not affect survival rate or phenotypic differentiation.
Related Products: 192-IgG-SAP (Cat. #IT-01)
Donepezil plus estradiol treatment enhances learning and delay-dependent memory performance by young ovariectomized rats with partial loss of septal cholinergic neurons.
Gibbs RB, Chipman AM, Nelson D (2011) Donepezil plus estradiol treatment enhances learning and delay-dependent memory performance by young ovariectomized rats with partial loss of septal cholinergic neurons. Horm Behav 59(4):503-511. doi: 10.1016/j.yhbeh.2011.01.011
Summary: Among the beneficial effects of estrogen on the brain are improved cognitive performance and prevention of age-related cognitive decline. These positive effects diminish over time following loss of ovarian function. To investigate the role of cholinergic neurons in this process, rats received 96-250 ng of 192-IgG-SAP (Cat. #IT-01) into the medial septal nucleus followed by a cholinergic enhancer and estradiol therapy. The dual therapy had a positive effect on partially lesioned animals, but did not improve the performance of animals with severe lesions.
Related Products: 192-IgG-SAP (Cat. #IT-01)
Lesion of cholinergic neurons in nucleus basalis enhances response to general anesthetics.
Leung LS, Petropoulos S, Shen B, Luo T, Herrick I, Rajakumar N, Ma J (2011) Lesion of cholinergic neurons in nucleus basalis enhances response to general anesthetics. Exp Neurol 228(2):259-269. doi: 10.1016/j.expneurol.2011.01.019
Summary: Consciousness and response to general anesthesia have been linked to acetylcholine in the brain. The authors treated rats with 150-ng bilateral injections of 192-IgG-SAP (Cat. #IT-01) into the nucleus basalis magnocellularis to examine this connection. Lesioned animals were more affected by propofol and phenobarbitol than control animals. Some effects of halothane were also increased. The data indicate a role for acetylcholine in the brain in the response to general anesthesia.
Related Products: 192-IgG-SAP (Cat. #IT-01)
Molsidomine promotes the recovery of cognitive deficit induced by 192 IgG saporin in rats
Hernandez MA, Hernández-Melesio M, Gonzalez-Ezquivel D, Quevedo-Corona L, Jiménez-Cataño M, Santoyo-Pérez M, Rios-Castañeda C, Pérez-Severiano F (2010) Molsidomine promotes the recovery of cognitive deficit induced by 192 IgG saporin in rats. Neuroscience 2010 Abstracts 856.27/I33. Society for Neuroscience, San Diego, CA.
Summary: The NO donor molsidomine (MOLS) has been used as a pharmacological tool in order to antagonize the cognitive deficit associated to cholinergic hypofunction produced by scopolamine. However, the participation of NO in the recovery of cholinergic deficit due to the administration of the cholinergic immunotoxin, 192 IgG saporin (SAP) has not been analyzed. The aim of the present study was to determine the effect of MOLS to counteract the cognitive deficits induced by cholinergic denervation in the object recognition task. Male Wistar rats were divided in the follow experimental groups according to the intraseptal administration of SAP and its vehicle PBS, and the injection (i.p) of the NO donor molsidomine and its vehicle saline: SAP (0.22 µg), PBS (0.1M pH 7.4), molsidomine (4mg/kg), SAP/molsidomine. The single dose of MOLS used in this study antagonized the cognitive failure related to SAP administration and increased the exploration time of novel object. We conclude that MOLS promote the acquisition of recognition memory in the model of cholinergic denervation associated to 192 IgG SAP and further immunohistological studies are being carried out in order to demonstrate that nitric oxide could have an effect over the cholinergic functionality.
Related Products: 192-IgG-SAP (Cat. #IT-01)
Effects of basal forebrain cholinergic lesions and estradiol on relative levels of estrogen receptor mRNAs in the rat forebrain
Hammond R, Shinde A, Gibbs RB (2010) Effects of basal forebrain cholinergic lesions and estradiol on relative levels of estrogen receptor mRNAs in the rat forebrain. Neuroscience 2010 Abstracts 611.16/MMM67. Society for Neuroscience, San Diego, CA.
Summary: Beneficial effects of estradiol on cognitive performance are lost in response to cholinergic denervation of the hippocampus and frontal cortex. Effects of estradiol also decline with age and time following the loss of ovarian function, which parallels naturally-occurring declines in basal forebrain cholinergic function. We hypothesize that cholinergic impairment may alter the expression of estrogen receptors in specific regions of the brain, thereby decreasing estradiol effects. In the present study, quantitative RT-PCR was used to evaluate the effects of septal cholinergic lesions ± estradiol treatment on relative levels of three estrogen receptors, ERα, ERß, and GPR30. Young adult ovariectomized (OVX) rats received intraseptal injections of saline or 192 IgG-saporin (a selective cholinergic immunotoxin). One week later, rats received either silastic capsules containing 17ß-estradiol or a blank capsule, implanted s.c. Seven days later, rats were killed and the brains were dissected. Tissues from the hippocampus, frontal cortex, prefrontal cortex, striatum, and septum were collected. RNA was extracted and relative levels of ER mRNA determined. Levels within each sample were normalized to levels of GAPDH. Differences between treatments and controls were calculated using the ΔΔCt method. Preliminary data indicate that septal cholinergic lesions produced significant decreases in relative levels of ERα and ERß mRNA in the hippocampus, and an increase in ERß mRNA in the frontal cortex. Estradiol alone produced decreases in levels of ERα, ERß, and GPR30 mRNA in the frontal cortex, decreased levels of ERα and ERß mRNA in the septum, and increased levels of ERα mRNA in the striatum. In rats with cholinergic lesions that also received estradiol, decreased levels of ERα mRNA were detected in hippocampus and septum, and decreased levels of ERß mRNA also were detected in septum. Data suggest that some of the effects of cholinergic denervation on ER mRNA expression may be mitigated by estradiol treatment. These data show that cholinergic lesions significantly affect ER mRNA expression in the brain, and that effects are region-specific. Such effects could account for the loss of beneficial effects of estradiol on cognitive performance in association with age and time following menopause, as well as in association with specific neurodegenerative diseases such as Alzheimer’s disease.
Related Products: 192-IgG-SAP (Cat. #IT-01)
Cholinergic modulation of both visual and olfactory attention with the five-choice serial reaction time test
Ljubojevic V, Luu P, De Rosa E (2010) Cholinergic modulation of both visual and olfactory attention with the five-choice serial reaction time test. Neuroscience 2010 Abstracts 535.8. Society for Neuroscience, San Diego, CA.
Summary: The nucleus basalis magnocellularis (NBM) sends acetylcholine (ACh) to neocortical regions that are involved in attentional cognitive processes. Using the five choice serial reaction time task (5CSRTT), the rodent analog of sustained attention in the human cognitive literature, it has been shown that a loss of cholinergic cells in the NBM causes impaired visual attentional performance in rats (Lehmann et al., 2003; McGaughy et al., 2002). The present research examined the neurochemical modulation of attentional processes using both a visual and an olfactory version of the 5CSRTT. To that purpose, we trained 14 male adult Long-Evans rats to attend and react to the briefly presented visual or odor stimuli until they achieved a stable performance under the baseline task conditions, i.e., low attentional demand with stimulus duration (SD) of 1s. Following the successful acquisition of both versions of the 5CSRTT, the rats were subjected to selective cholinergic lesions of the NBM with the cholinergic immunotoxin 192 IgG-saporin to remove the cholinergic innervation from the neocortical mantle. This allowed an examination of the role of ACh in modulation of visual and olfactory attention. After the two week post-surgical recovery period, we compared the attentional performance of the saporin-lesioned (SAP) group (N=8) to that of the sham-lesioned (SHAM) group (N=6) on the two versions of the 5CSRTT task. We observed the impaired attentional performance of the SAP rats on the visual 5CSRTT under the baseline conditions (SD=1s); shortening the SD = 0.5s increased the extent of their deficits. With the olfactory 5CSRTT, the SAP impairment was only observed under the attentional challenge of SD=0.5s. However, in both modalities the difference between two groups trended toward statistical significance due to the low number of the experimental subjects in each group. We are currently performing further parametric manipulations to further challenge the rats in both modalities. We will then collect data from an additional 14 rats to increase the statistical power of our experiment. After the completion of the behavioral data collection, we will conduct acetylcholinesterase histochemistry and choline acetyltransferase immunohistochemistry in order to determine the extent of the loss of cholinergic afferents in fronto-parietal target cortical areas and the loss of cholinergic cell bodies in the NBM, respectively. In addition, parvalbumin immunohistochemistry will be carried out to quantify GABA-releasing neurons colocalized in NBM to confirm the selectivity of our lesion.
Related Products: 192-IgG-SAP (Cat. #IT-01)
The effects of neonatal cholinergic lesion on age-related changes in behaviour, neurogenesis and CA1 pyramidal cell morphology
Rennie KE, Frechette M, Pappas BA (2010) The effects of neonatal cholinergic lesion on age-related changes in behaviour, neurogenesis and CA1 pyramidal cell morphology. Neuroscience 2010 Abstracts 349.8/J12. Society for Neuroscience, San Diego, CA.
Summary: Age-related cognitive decline is associated with dysfunction of the basal forebrain cholinergic (BFC) system, and cortico-hippocampal cholinergic denervation is a hallmark neurochemical feature of the Alzheimer’s-afflicted brain. It has been suggested that cognitive deficits that emerge with age may be rooted in early dysfunction of the BFC system and that impaired cholinergic transmission might interact with ageing-associated factors to produce cognitive decline. The purpose of this study was to examine the effects of neonatal cholinergic lesion on age-related changes in spatial working memory, neurogenesis and hippocampal CA1 pyramidal cell morphology. We have previously reported that neonatal cholinergic lesion results in only minor behavioural deficits, but impairs the birth and/or survival of new neurons and reduces CA1 dendritic complexity in the young adult rat. We hypothesized that memory impairments would become apparent in lesioned rats as they age, and that this impairment would be accompanied by more drastic reductions in neurogenesis and cytoarchitectural alterations than those that have been documented in the young adult animal after neonatal cholinergic lesion. Seven-day-old male Sprague-Dawley rats were subjected to basal forebrain cholinergic lesion by infusion of the cholinotoxin 192-IgG-Saporin into the lateral ventricles. At the age of 12 or 21 months, the rats were tested on a working memory version of the Morris water maze. While aging had only a slight effect on the memory performance of control rats, lesioned rats showed pronounced memory impairments with age. This occurred without CA1 cell loss or astrogliosis in 21-month-old lesioned rats when compared to age-matched controls. However, golgi analysis revealed that while cholinergic lesion did not alter the total dendritic length, branching, number of spines, or spine density of CA1 pyramidal cells in 21-month-old rats, the distribution of these parameters across branch orders was shifted. The lesion caused a slight reduction in apical branch length and spine density, and basal branch number, length and number of spines at low/middle branch orders, but increased these parameters at upper branch orders. Thus, perinatal cholinergic lesion precipitates spatial memory dysfunction during old age, and this seems to be associated with cytoarchitectural changes to neurons rather than neuronal loss.
Related Products: 192-IgG-SAP (Cat. #IT-01)
Mesolimbic-basal forebrain circuitry mediating the motivational activation of attention
St Peters MM, Bruno JP, Sarter M (2010) Mesolimbic-basal forebrain circuitry mediating the motivational activation of attention. Neuroscience 2010 Abstracts 506.12/LLL52. Society for Neuroscience, San Diego, CA.
Summary: Prefrontal circuitry mediating cue detection is modulated by the tonic component of cholinergic activity. Performance-associated increases in tonic cholinergic activity are augmented by demands on the cognitive control of attention. Highest levels of tonic cholinergic activity are observed while animals perform below baseline as a result of, for example, a distractor, but while they remain motivated to stabilize and recover attentional performance. Cortico-mesolimbic-basal forebrain circuitry is thought to mediate such motivated activation of attentional performance. We previously observed that stimulation of ionotropic glutamate receptors in the shell of the nucleus accumbens (NAs) stimulates tonic cholinergic activity in the prefrontal cortex. Here we test the hypothesis that such stimulation benefits attentional performance while distractors evoke cognitive control. Rats were trained in an operant sustained attention task (SAT) before undergoing surgery for implantation of a bilateral guide cannula targeting the NAs or, in separate animals, the core of the NA (NAc). NMDA (0.01-0.15 µg/0.5 µL/hemisphere) or vehicle (0.9% saline) was infused bilaterally into task-performing animals during SAT and the more challenging distractor version (dSAT). For the dSAT, the operant chamber ceiling lights flashed on/off at 0.5 Hz during the middle block of three blocks of trials that constituted a session. NMDA infusions in the NAs, but not into the NAc, significantly improved the animals’ attentional performance in the presence of the distractor. These findings are consistent with the hypothesis that activation of the NAs mediates attentional performance under conditions that require top-down control. The next set of experiments determined whether the effects of NAs activation require the cortical cholinergic system. We infused the immunotoxin 192 IgG saporin into prefrontal or parietal regions, in addition to implantation of guide cannula targeting the NAs. Replicating the initial finding, NAs NMDA infusions enhanced dSAT performance. Both PFC and PPC cholinergic deafferentation prevented this effect of NMDA. These findings suggest that the motivated activation of the cholinergic attention system during demands on top-down control modulates fronto-parietal attention networks to optimize attentional performance.
Related Products: 192-IgG-SAP (Cat. #IT-01)