References

Prater C, Harris B, Merrill A, Aliyas A, Anderson K, Carr J (2016) Tectal CRF R1 receptors modulate food intake. Neuroscience 2016 Abstracts 257.08 / DDD9. Society for Neuroscience, San Diego, CA.

Summary: The optic tectum (OT) and superior colliculus (SC) rapidly inhibit food intake when a visual threat is present. Previous work from our laboratory indicates that CRF, acting on CRF R1 receptors, may play a role in tectal inhibition of prey capture. Here we test the hypothesis that tectal CRF neurons modulate food intake in juvenile Xenopus laevis. We tested five predictions: 1) Does tectal CRF injection decrease food intake? 2) Does a selective CRF R1 antagonist block CRF effects on feeding? 3) Does a selective CRF R1 antagonist block stressor-induced inhibition of feeding? 4) Does eliminating tectal cells expressing CRF R1 increase feeding? 5) Does food deprivation increase food intake and, if so, can this be reversed with CRF? X. laevis were administered oCRF alone or in combination with the selective CRF R1 antagonist NBI27914 or antagonist vehicle. Test agents were bilaterally injected into the tecta of juvenile frogs. CRF conjugated to the ribosomal toxin saporin (CRF-SAP) was administered 2 wk prior to testing to eliminate tectal cells expressing CRF R1. oCRF administered bilaterally into the tecta significantly reduced food intake compared to sham and vehicle injected juveniles. When frogs were injected with oCRF and antagonist vehicle, food intake was significantly reduced. When injected with both NBI27914 and oCRF, food intake was maintained at baseline levels. Frogs ate significantly less when exposed to a reactive stressor (ether vapors) and when pre-treated with antagonist vehicle prior to exposure. NBI27914 reversed stressor-induced inhibition of food intake. Neither CRF-SAP injection nor food deprivation (2 wk) significantly changed food intake. No significant differences in food intake were noted between males and females across all studies. Overall, we found support for questions 1-3 and conclude that activation of the tectal CRF R1 inhibits food intake in frogs. Furthermore, tectal CRF R1 receptors appear to be involved in the reduction of food intake that occurs in response to a reactive stressor. However, elimination of tectal CRF R1 neurons did not increase feeding suggesting that this system may be more important for stress-related vs. baseline feeding. This work was done in partial completion of requirements for the doctoral degree at Texas Tech University (C.P.)

Related Products: CRF-SAP (Cat. #IT-13)

Staib JM, Knox D (2016) The role of cholinergic input from the medial septum in cued and contextual fear extinction memory. Neuroscience 2016 Abstracts 262.11 / III7. Society for Neuroscience, San Diego, CA.

Summary: In classical fear conditioning, a neutral stimulus (CS) is paired with an aversive stimulus (US), causing the animal to associate the US with CS, and display a fear response to the CS. Fear extinction occurs when the CS is presented without the US and the animals learn that the CS no longer predicts the US, thus learning to no longer show fear with CS presentation. Ventral medial prefrontal cortex inhibition of neural activity in basolateral and central amygdala nuclei is critical for extinction memory formation. Recently, we observed that cholinergic lesions in the Medial Septum and Diagonal Bands of Broca (MS/DBB), induced with 192-IgG saporin results in fear extinction memory deficits and contextual fear memory generalization between the conditioning and extinction contexts. While this suggests that MS/DBB cholinergic neurons may be a component of the fear extinction circuit, these neurons project to many brain regions. As a result, the MS/DBB cholinergic efferents that are critical for mediating extinction memory and contextual fear memory discrimination are unknown. The goal of the present study is to isolate the exact MS/DBB efferents that mediate extinction memory and contextual fear memory discrimination. While the study is in progress, some results have been collected. Cholinergic lesions in the dorsal hippocampus, ventral hippocampus, and medial prefrontal cortex have no effects on fear extinction memory or contextual fear memory discrimination. This is surprising because all of these regions are components of the fear extinction circuit and the dorsal hippocampus is critical for contextual learning during acquisition of fear and extinction memory. The MS/DBB also projects to habenula nuclei, and there are cholinergic interneurons in the MS/DBB as well. For the remainder of the study, we explore the potential role of MS/DBB cholinergic input to the habenula and MS/DBB cholinergic interneurons in mediating extinction memory and contextual fear memory discrimination. Isolating a region that has a direct role in mediating extinction memory could help focus future research in fear memory disorders like post traumatic stress disorder.

Related Products: 192-IgG-SAP (Cat. #IT-01)

Cho J, Lee J, Jeong D, Kim H, Chang W, Moon J, Chang J (2016) Placenta-derived mesenchymal stem cells facilitate neural and cognitive recovery in dementia rat model. Neuroscience 2016 Abstracts 38.10 / G29. Society for Neuroscience, San Diego, CA.

Summary: Introduction: Dementia is a term that encompasses various types of neurodegenerative diseases of the brain that cause a gradual decline in mental abilities. Loss of cholinergic neurons in the brain cholinergic system including the hippocampus is a hallmark of many dementia cases. In this study, we report the therapeutic effects of administration of human placenta-derived mesenchymal stem cells (pMSCs) in dementia model Sprague-Dawley (SD) rats using two different cell injection methods: intracerebroventricular (ICV) and intravenous (IV) injections. Methods: Dementia modeling was carried out by intraventricular injection of 192 IgG saporin, which causes lesion of cholinergic neurons. Fifty male SD rats were divided into four groups: normal (n=9), lesion (n=9), ICV (n=12) and IV (n=12). All rats were then subject to Morris water maze test and subsequent immunostaining analyses using markers for human cytoplasm, acetylcholinesterase (AChE), choline acetyltransferase (ChAT) and microglial cells at the hippocampus. Results: Lesioned rats showed poor performance in the Morris water maze test compared to the normal rats. Both ICV and IV pMSC administration allowed significant cognitive recovery compared to the lesioned rats. AChE was also significantly recovered back to normal levels at the hippocampus in rats injected with pMSCs post-lesion. ChAT did not co-localize with pMSCs, showing that pMSCs did not directly differentiate into cholinergic cells. Stem cell count showed a significantly greater number of pMSCs at the hippocampal dentate gyrus in IV group rats compared to ICV group rats. Number of microglial cells increased in lesioned rats, and was significantly reduced back to normal levels after pMSC injection. Discussion: Our results demonstrate that injection of pMSCs facilitates recovery of cholinergic neuronal population and function, as well as cognitive behavior. The mechanism through which such recovery happens does not seem to be direct differentiation of injected pMSCs into cholinergic neurons, but rather seems to be through paracrine effects that resemble microglial function. Further research will be necessary for elucidation of the exact mechanisms involved and establishment of optimal parameters for successful cell homing. Acknowledgements: This study was supported by the grant from the Yonsei University Future-leading Research Initiative (Yonsei Challenge) of 2015 (2015-22-0137) and Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Science, ICT and Future Planning (2015R1C1A1A02036851).

Related Products: 192-IgG-SAP (Cat. #IT-01)

Urquhart M, Reyes BAS, Thomas SA, Mackie K, Van Bockstaele EJ (2016) Diacylglycerol lipase-α expression increases in the coeruleo-cortical pathway in dopamine-β-hydroxylase knockout mice as well as rats treated with DSP-4. Neuroscience 2016 Abstracts 77.09 / AAA24. Society for Neuroscience, San Diego, CA.

Summary: Endocannabinoids are involved in the regulation of many physiological processes including behavioral responses to stress. Endocannabinoids modulate norepinephrine (NE) signaling primarily via involvement of CB1 cannabinoid receptors (CB1r). Our previous studies have shown that acute and repeated administration of a CB1r agonist increases multiple indices of noradrenergic activity involving the locus coeruleus (LC)-frontal cortex (FC) pathway. Diacylglycerol lipase-α (DGL-α), a key enzyme in the biosynthesis of the endocannabinoid 2-arachidonoylglycerol (2-AG) is localized to both the FC and the LC. Using electron microscopy, we have recently shown that in the rat FC DGL-α is localized in postsynaptic profiles that are targeted by dopamine-β-hydroxylase (DβH), the enzyme that converts dopamine to norepinephrine and represents a marker of noradrenergic neurons (Hartman et al., 1972). In this study, we also described interactions between DGL-α, CB1r and DβH in the FC using confocal microscopy. In the present study, we investigated expression levels of DGL-α under two conditions of NE deletion: in a rat model using a systemic injection of saporin conjugated with antibody against DβH (DSP-4) and in a genetically engineered mouse that lacked the enzyme DβH (DβH-knockout, KO). We compared expression levels of DGL-α to either control rats or wild type (WT) mice using Western blot analysis. Protein extracts from micropunches of FC and LC were obtained and probed for DGL-α. Results showed that DGL-α expression was significantly increased in FC (P < 0.05) of both DSP-4 treated rats and DβHKO mice when compared to WT mice. DGL-α expression was also significantly increased in the LC (P < 0.05) of DβHKO when compared to WT mice. These data add to the accumulating evidence that dysregulation of NE transmission results in significant adaptations in the brain endocannabinoid system.

Related Products: Anti-DBH-SAP (Cat. #IT-03)

Naylor R, McGhee C, Cowan C, Davidson A, Holm T, Sherwin T (2016) Derivation of corneal keratocyte-like cells from human induced pluripotent stem cells. PLoS One 11:e0165464. doi: 10.1371/journal.pone.0165464 PMID: 27792791

Summary: Slides containing cryosections were dried overnight at 4°C and then washed twice in Tris Buffered Saline containing 0.1% Triton X100 (TBST). Slides were then placed in block solution (3% BSA, 5% Goat serum in TBST) for at least one hour. The primary antibody was then applied in the same block solution (1:100) and left overnight at 4°C.

Related Products: NGFr (ME20.4, p75) Mouse Monoclonal (Cat. #AB-N07)

Benn A, Robinson E (2017) Differential roles for cortical versus sub-cortical noradrenaline and modulation of impulsivity in the rat. Psychopharmacology (Berl) 234:255-266.. doi: 10.1007/s00213-016-4458-8

Summary: Atomoxetine is a noradrenaline re-uptake inhibitor licensed for the treatment of adult and childhood attention deficit hyperactivity disorder. Although atomoxetine has established efficacy, the mechanisms which mediate its effects are not well understood. In this study, the authors investigated the role of cortical versus sub-cortical noradrenaline by using focal dopamine beta hydroxylase-saporin-induced lesions, to the prefrontal cortex (PFC) or nucleus accumbens shell (NAcSh). Male Lister hooded rats received bilateral lesions by using stereotaxic injections of the immunotoxin Anti-DβH-SAP (Cat. #IT-03), 0.02 μg in 0.5 μL per injection into the PFC and 0.004 μg in 0.2 μL per injection for NAcSh lesions. The data suggest that noradrenaline in the nucleus accumbens shell plays an important role in the effects of atomoxetine. Under these conditions, prefrontal cortex noradrenaline did not appear to contribute to atomoxetine’s effects suggesting a lack of cortical-mediated “top-down” modulation. Noradrenaline in the prefrontal cortex appears to contribute to the modulation of impulsive responding in amphetamine-treated animals, with a loss of noradrenaline associated with potentiation of its effects. These data demonstrate a potential dissociation between cortical and sub-cortical noradrenergic mechanisms and impulse control in terms of the actions of atomoxetine and amphetamine.

Related Products: Anti-DBH-SAP (Cat. #IT-03)

Nam H, Kerman I (2016) A2 noradrenergic neurons regulate forced swim test immobility. Physiol Behav 165:339-349. doi: 10.1016/j.physbeh.2016.08.020

Summary: Wistar-Kyoto rats are often used as a model of depression, and exhibit high levels of immobility when subjected to a forced swim test (FST). Researchers discovered relative hyperactivation in the locus coeruleus of WKY rats compared to the genetically related Wistar rats when exposed to one- and two-day FSTs. Lesser activation of A2 noradrenergic cell group was seen by diminished levels of FOS after both days of the FST. A2 noradrenergic neurons of Winstar rats were lesioned by injecting 2.2 ug of Anti-DBH-SAP (Cat. #IT-03) into the nucleus tractus solitaris (NTS). Lesioned rats exhibited increased FST immobility on both days of the test, similar to natural WKY behavior in the same test. These data indicate that the A2 noradrenergic cell group regulates FST behavior and that its hypoactivation may contribute to the unique behavioral phenotype of WKY rats.

Related Products: Anti-DBH-SAP (Cat. #IT-03)

Kaushal R, Taylor B, Jamal A, Zhang L, Ma F, Donahue R, Westlund K (2016) GABA-A receptor activity in the noradrenergic locus coeruleus drives trigeminal neuropathic pain in the rat; contribution of NAα1 receptors in the medial prefrontal cortex. Neuroscience 334:148-159. doi: 10.1016/j.neuroscience.2016.08.005

Summary: The goal of this study was to investigate the role of the locus coeruleus (LC) in a rat orofacial pain model of trigeminal neuropathy induced by chronic constrictive injury of the infraorbital nerve (CCI-ION). Mechanical thresholds to von Frey filaments were tested on whisker pads to evaluate neuropathic pain behavior; pain was indicated by development of mechanical hypersensitivity. Noradrenergic (NA) neurons were lesioned with 5-mcg injections of Anti-DBH-SAP (Cat. #IT-03) into the left lateral ventricle. Mouse-IgG-SAP (Cat. #IT-18) was used as a control. After ablation of NA neurons there was a notable increase in the mechanical threshold compared to control animals. They also targeted coeruleotrigeminal NA neurons by injecting Anti-DBH-SAP into the trigeminal brainstem nuclei bilaterally in one animal and saw similar results. Injecting a GABAA receptor antagonist into the LC after injury had an inhibitory effect on nerve injury induced hypersensitivity. Injection of a NAα1 receptor antagonist, but not a NAα2 receptor antagonist, into the medial prefrontal cortex (mPFC) alleviates mechanical hypersensitivity. They conclude that GABAA-mediated activation of NA neurons during CCI-ION can facilitate hypersensitivity through NAα1 receptors in the mPFC, and that the LC is a chronic pain generator.

Related Products: Anti-DBH-SAP (Cat. #IT-03), Mouse IgG-SAP (Cat. #IT-18)

Kang BR, Yang SH, Chung BR, Kim W, Kim Y (2016) Cell surface GRP78 as a biomarker and target for suppressing glioma cells. Sci Rep 6:34922. doi: 10.1038/srep34922. PMID: 27713511

Summary: The publication discusses the identification of cell surface GRP78 as a promising biomarker for glioma, a type of brain tumor. Furthermore, it highlights the potential of targeting cell surface GRP78 as a strategy to suppress glioma cells, offering new insights into the development of therapeutic approaches for this challenging disease.

Paban V, Valable S, Baril N, Gilbert V, Chambon C, & Alescio-Lautier B (2016) Neuronal and glial changes in rat hippocampal formation after cholinergic deafferentation. J Biomol Res Ther 5(3):1000147. doi: 10.4172/2167-7956.1000147

Summary: The effects of cholinergic insult were studied in the hippocampal formation of cholinergic lesioned rats at metabolic and cellular levels by in vivo nuclear magnetic resonance spectrometry and immuno-histochemical approaches.

Usage: Cholinergic deafferentation was induced by injection of the cholinergic immunotoxin 192-IgG-SAP into the medial septum (37.5 ng/side).

Related Products: 192-IgG-SAP (Cat. #IT-01)