BACKGROUND:Alzheimer's disease (AD) animal models have revealed neuroprotective actions of Bryostatin-1 mediated by activation of novel PKC isoforms, suppression of beta-amyloid and downregulation of inflammatory and angiogenic events, making Bryostatin-1 an attractive candidate for attenuating AD-associated neural, vascular, and cognitive disturbances.OBJECTIVE:To further enhance Bryostatin-1 efficacy, nanoparticle-encapsulated Bryostatin-1 formulations were prepared.METHODS:We compared nano-encapsulated and unmodified Bryostatin-1 in in vitro models of neuronal PKC-d, PKC-e isoforms, α-secretase and studied nano-encapsulated Bryostatin-1 in an AD mouse model of spatial memory (BC3-Tg (APPswe, PSEN1 dE9) 85Dbo/J mice).RESULTS:We found that nanoencapsulated Bryostatin-1 formulations displayed activity greater or equal to that of unmodified Bryostatin-1 in PKC-δ and -ε and α-secretase activation assays. We next evaluated how treatment with a nanoencapsulated Bryostatin-1 formulation facilitated spatial learning in the Morris water maze. AD transgenic mice (6.5 to 8 months of age) were treated with nanoparticle encapsulated Bryostatin-1 formulation (1, 2.5, or 5 μg/mouse) three times the week before testing and then daily for each of the 5 days of testing. Across the acquisition phase, mice treated with nanoencapsulated Bryostatin-1 had shorter latencies, increased % time in the target zone and decreased % time in the opposite quadrant. The mice were given retention testing after a 2-week period without drug treatment. Mice treated with nanoencapsulated Bryostatin-1 had shorter latencies to find the escape platform, indicating retention of spatial memory.CONCLUSION:These data suggest that cognitive deficits associated with AD could be treated using highly potent nanoparticle-encapsulated formulations of Bryostatin-1.

Background Opioids are the most effective drugs commonly prescribed to treat pain. Due to their addictive nature, opioid pain relievers are now second to marijuana, ahead of cocaine with respect to dependence. Ours and other studies suggest potential toxic effects of chronic opioid administration leading to neuronal degeneration. It has been suggested that protein carbonylation may represent a sensitive biomarker of cellular degeneration. To evaluate whether prolonged oxycodone administration is associated with accumulation of protein aggregates that may contribute to neuronal degeneration we measured protein carbonylation levels in brain and also in blood plasma of rats after 30-days of 15 mg/kg daily oxycodone administration. Results We observed a significant increase in the level of carbonylated proteins in rat brain cortex after 30-days of oxycodone treatment compare to that in water treated animals. Also, oxycodone treated rats demonstrated accumulation of insoluble carbonyl-protein aggregates in blood plasma. Conclusions Our data suggests that tests detecting insoluble carbonyl-protein aggregates in blood may serve as an inexpensive and minimally invasive method to monitor neuronal degeneration in patients with a history of chronic opioid use. Such methods could be used to detect toxic side effects of other medications and monitor progression of aging and neurodegenerative diseases.

Chronic opioid therapy for non-malignant pain conditions has significantly increased over the last 15 years. Recently, the correlation between opioid analgesics and alternations in brain structure, such as leukoencephalopathy, axon demyelination, and white matter lesions, has been demonstrated in patients with a history of long-term use of prescription opioids. The exact mechanisms underlying the neurotoxic effect of opioids on the central nervous system are still not fully understood. We investigated the effect of chronic opioids using an animal model in which female rats were orally gavaged with 15 mg/kg of oxycodone every 24 h for 30 days. In addition we tested oxycodone, morphine and DAMGO in breast adenocarcinoma MCF7 cells, which are known to express the μ-opioid receptor.

BACKGROUND:Proteomic analysis of cerebrospinal fluid (CSF) has shown great promise in identifying potential markers of injury in neurodegenerative diseases [1-13]. Here we compared CSF proteomes in healthy individuals, with patients diagnosed with traumatic brain injury (TBI) and subarachnoid hemorrhage (SAH) in order to characterize molecular biomarkers which might identify these different clinical states and describe different molecular mechanisms active in each disease state.METHODS:Patients presenting to the Neurosurgery service at the Louisiana State University Hospital-Shreveport with an admitting diagnosis of TBI or SAH were prospectively enrolled. Patients undergoing CSF sampling for diagnostic procedures were also enrolled as controls. CSF aliquots were subjected to 2-dimensional gel electrophoresis (2D GE) and spot percentage densities analyzed. Increased or decreased spot expression (compared to controls) was defined in terms of in spot percentages, with spots showing consistent expression change across TBI or SAH specimens being followed up by Matrix-Assisted Laser Desorption/Ionization mass spectrometry (MALDI-MS). Polypeptide masses generated were matched to known standards using a search of the NCBI and/or GenPept databases for protein matches. Eight hundred fifteen separately identifiable polypeptide migration spots were identified on 2D GE gels. MALDI-MS successfully identified 13 of 22 selected 2D GE spots as recognizable polypeptides.RESULTS:Statistically significant changes were noted in the expression of fibrinogen, carbonic anhydrase-I (CA-I), peroxiredoxin-2 (Prx-2), both α and β chains of hemoglobin, serotransferrin (Tf) and N-terminal haptoglobin (Hp) in TBI and SAH specimens, as compared to controls. The greatest mean fold change among all specimens was seen in CA-I and Hp at 30.7 and -25.7, respectively. TBI specimens trended toward greater mean increases in CA-I and Prx-2 and greater mean decreases in Hp and Tf.CONCLUSIONS:Consistent CSF elevation of CA-I and Prx-2 with concurrent depletion of Hp and Tf may represent a useful combination of biomarkers for the prediction of severity and prognosis following brain injury.

Oxycodone (6‐deoxy‐7,8‐dehydro‐14‐hydroxy‐3‐O‐methyl‐6‐oxomorphine) is a strong semi‐synthetic opioid. It is prescribed to treat different types of pain especially when other opioids are ineffective. Oxycodone has close structural similarity to morphine and heroin and binds not only m‐ but also k‐opioid receptors. Unfortunately, similar to other opioids, repetitive oxycodone administration has the potential to develop analgesic tolerance, withdrawal, and addiction. Recently, another concern regarding the effect of chronic or over‐dose opioid exposure has emerged: their effect on neuronal degeneration. Leukoencephalopathy or damage of white matter has been described as one of the effects that heroin abusers develop, and was recently documented in a patient after morphine and oxycodone administration. The exact mechanisms underlying the neurotoxic effect of opioids on the Central Nervous System are still not fully understood. To investigate the effect of opioid treatment on rat white matter we used an animal model in which female rats were gavaged with 15 mg/kg oxycodone every 24 hours for 30 days. In our study we observed that chronic oxycodone exposure induces oxidative/nitrosidative stresses in three brain areas in rats: nucleus accumbens, cortex and brain stem. We demonstrated activation of pro‐apoptotic machinery in rat brains after oxycodone treatment. Interestingly, activated caspase 3 was predominantly localized in areas containing white matter suggesting increased axonal damages after chronic oxycodone exposure. The increased level of a‐synuclein aggregates and amyloid precursor protein (APP) in oxycodone‐exposed cerebellum confirmed the axonal injury. We also demonstrated induction of pro‐apoptotic protein Bax by oxycodone, morphine and DAMGO in breast carcinoma cells MCF7, which are known to express the m‐opioid receptor. Support or Funding Information LMS was supported by Grant No. 2R01GM20818 from the National Institute of General Medical Sciences.

Oxycodone is an opioid that is prescribed to treat multiple types of pain, especially when other opioids are ineffective. Unfortunately, similar to other opioids, repetitive oxycodone administration has the potential to lead to development of analgesic tolerance, withdrawal, and addiction. Studies demonstrate that chronic opioid exposure, including oxycodone, alters gene expression profiles and that these changes contribute to opioid-induced analgesic effect, tolerance and dependence. However, very little is known about opioids altering the translational machinery of the central nervous system. Considering that opioids induce clinically significant levels of hypoxia, increase intracellular Ca2+ levels, and induce the production of nitric oxide and extracellular glutamate transmission, we hypothesize that opioids also trigger a defensive mechanism called the integrated stress response (ISR). The key event in the ISR activation, regardless of the trigger, is phosphorylation of translation initiation factor 2 alpha (eIF2α), which modulates expression and translational activation of specific mRNAs important for adaptation to stress. To test this hypothesis, we used an animal model in which female rats were orally gavaged with 15 mg/kg of oxycodone every 24 h for 30 days.

Environmental enrichment (EE) housing paradigms have long been shown beneficial for brain function involving neural growth and activity, learning and memory capacity, and for developing stress resiliency. The expression of the α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor subunit GluA2, which is important for synaptic plasticity and memory, is increased with corticosterone (CORT), undermining synaptic plasticity and memory. Thus, we determined the effect of EE and stress on modulating GluA2 expression in Sprague-Dawley male rats. Several markers were evaluated which include: plasma CORT, the glucocorticoid receptor (GR), GluA2, and the atypical protein kinase M zeta (PKMζ). For 1 week standard-(ST) or EE-housed animals were treated with one of the following four conditions: (1) no stress; (2) acute stress (forced swim test, FST; on day 7); (3) chronic restraint stress (6 h/day for 7 days); and (4) chronic + acute stress (restraint stress 6 h/day for 7 days + FST on day 7). Hippocampi were collected on day 7. Our results show that EE animals had reduced time immobile on the FST across all conditions. After chronic + acute stress EE animals showed increased GR levels with no change in synaptic GluA2/PKMζ. ST-housed animals showed the reverse pattern with decreased GR levels and a significant increase in synaptic GluA2/PKMζ. These results suggest that EE produces an adaptive response to chronic stress allowing for increased GR levels, which lowers neuronal excitability reducing GluA2/PKMζ trafficking. We discuss this EE adaptive response to stress as a potential underlying mechanism that is protective for retaining synaptic plasticity and memory function.

Prescription opioid abuse is a growing healthcare concern in this country. In particular recent data have shown substantial increases in use among the young and women in comparison to more traditional abused opioids like heroin. The changing demographics of opioid abuse are leading to rises in neonatal narcotic abstinence syndromes (NNAS), which can require substantial hospitalization. In addition to NNAS there can be long-term effects on health and behavior. To characterize the acute and longer-term effects, rodent models of prenatal opioid exposure have been developed. The majority of models have considered exposure to methadone, morphine, and heroin. We will review the data from these models, as well as more recent data on prenatal exposure to prescription opioids. We also consider the acute effects of the drugs in utero and the early postnatal period, as well as longer-term effects in the juvenile and adult.

Oxycodone (6‐deoxy‐7,8‐dehydro‐14‐hydroxy‐3‐O‐methyl‐6‐oxomorphine) is a semi synthetic opioid. It is most effective for treating patients with post‐surgical, cancer and chronic non‐malignant pain. Recently concern regarding effect of chronic opioid exposure on the development of neuronal degeneration has been emerged. We have investigated induction of biomarkers of brain pathology by chronic oxycodone exposure in rats. We observed significant mitochondrial dysfunction and increase in activated caspase 3 level in brain of rats treated with oxycodone. Recently, it was shown that opioid receptors may be involved in amyloid‐beta production that is one of the characteristics of Alzheimer disease. Thus, we monitored the level of amyloid beta A4 protein. We detected increased accumulation of amyloid beta A4 protein in both nucleus accumbens and cortex areas of oxycodone‐exposed rats. We also observed increase in a‐synuclein level in various brain areas after oxycodone treatment. These data indicates that chronic oxycodone exposure may contribute to premature development of neuronal degeneration in brain areas involved in motivational, memory and executive controls.

It is well established that male rats have an advantage in acquiring place-learning strategies, allowing them to learn spatial tasks more readily than female rats. However many of these differences have been examined solely during acquisition or in 24h memory retention. Here, we investigated whether sex differences exist in remote long-term memory, lasting 30d after training, and whether there are differences in the expression pattern of molecular markers associated with long-term memory maintenance. Specifically, we analyzed the expression of protein kinase M zeta (PKMζ) and the α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor subunit GluA2. To adequately evaluate memory retention, we used a robust training protocol to attenuate sex differences in acquisition and found differential effects in memory retention 1d and 30d after training. Female cohorts tested for memory retention 1d after 60 training trials outperformed males by making significantly fewer reference memory errors at test. In contrast, male cohorts tested 30d after 60 training trials outperformed females of the same condition, making fewer reference memory errors and achieving significantly higher retention test scores. Furthermore, given 60 training trials, females tested 30d later showed significantly worse memory compared to females tested 1d later, while males tested 30d later did not differ from males tested 1d later. Together these data suggest that with robust training males do no retain spatial information as well as females do 24h post-training but maintain this spatial information for longer. Males also showed a significant increase in synaptic PKMζ expression and a positive correlation with retention test scores, while females did not. Interestingly, both sexes showed a positive correlation between retention test scores and synaptic GluA2 expression. Furthermore, the increased expression of synaptic PKMζ, associated with male memory but not with female memory, identifies another potential sex-mediated difference in memory processing.

GluA2-containing AMPA receptors and their association with protein kinase M zeta (PKMζ) and post-synaptic density-95 (PSD-95) are important for learning, memory and synaptic plasticity processes. Here we investigated these synaptic markers in the context of an acute 1h platform stress, which can disrupt spatial memory retrieval for a short-term memory on the object placement task and long-term memory retrieval on a well-learned radial arm maze task. Acute stress increased serum corticosterone and elevated the expression of synaptic PKMζ while decreasing synaptic GluA2. Using co-immunoprecipitation, we found that this stressor promotes the clustering of GluA2, PKMζ and PSD-95, which is consistent with effects reported from overexpression of PKMζ in cell culture. Because PKMζ overexpression has also been shown to induce spine maturation in culture, we examined how stress impacts synaptic markers within changing spines across various hippocampal subfields. To achieve this, we employed a new technique combining Golgi staining and immmunohistochemistry to perform 3D reconstruction of tertiary dendrites, which can be analyzed for differences in spine types and the colocalization of synaptic markers within these spines. In CA1, stress increased the densities of long-thin and mushroom spines and the colocalization of GluA2/PSD-95 within these spines. Conversely, in CA3, stress decreased the densities of filopodia and stubby spines, with a concomitant reduction in the colocalization of GluA2/PSD-95 within these spines. In the outer molecular layer (OML) of the dentate gyrus (DG), stress increased both stubby and long-thin spines, together with greater GluA2/PSD-95 colocalization. These data reflect the rapid effects of stress on inducing morphological changes within specific hippocampal subfields, highlighting a potential mechanism by which stress can modulate memory consolidation and retrieval.

The activation of the alpha‐secretase pathway appears to be a critical therapeutic advance in Alzheimerˈs disease. There are two important classes of agents which can activate this pathway, the benzolactam/indolactams and bryostatin/bryologues. Both appear to modulate APP processing through PKC dependent pathways, but a direct comparison of these two classes in a neuronal cell line has not been performed. In this study, SH‐SY5Y neuroblastoma cells were selected as a model and dilutions of Bryostatin‐1 or TPPB were added to serum‐free culture medium to final concentration for 3h, except in time‐course experiments. After treatment, alpha‐secretase activity and translocation of PKC isoforms were detected by western blotting. Our results showed Bryostatin‐1 induces s‐APPa release in SH‐SY5Y cells at several orders of magnitude lower concentration, and at earlier time points than TPPB. We also found Bryostatin‐1 activates PKC‐a, PKC‐d and PKC‐e translocation in SH‐SY5Y cells at 10‐8M, 10‐9M and 10‐10M and different time points, howere TPPB only induced PKC‐a translocation at 10‐9M at 3h. Bryostatin‐1 thus appears to exert a more rapid, potent and sustained activation of APP processing which is associated with its much more potent and specific activation of PKC‐d and PKC‐e at lower doses.This research was supported by a grant from the NIA and NIH (1R44AG034760‐01A1)

Recent research suggests that Bryostatin‐1 is neuroprotective via activation of protein kinase C isoforms, down regulation of pro‐inflammatory factors and angiogenic processes and the suppression of beta amyloid. Alzheimer's disease (AD) has been associated with these factors and therefore Bryostatin‐1 is an attractive candidate for ameliorating AD cognitive deficits. We evaluated the ability of Bryostatin‐1 to restore learning and memory in the BC3‐Tg(APPswe, PSEN1 dE9) 85Dbo/J mouse model of AD. This strain incorporates the human ‘Swedish’ (swe) amyloid precursor protein and presenilin mutations, which are associated with progressive human AD. A stable oil formulation of Bryostatin‐1 (5 μg/mouse) was administered by oral gavage 3 times the week prior to testing and then daily during 5 days of Morris Water Maze testing (4 trials per day). Treated mice were compared to untreated transgenic controls and wild‐type mice. Tg AD mice treated with Bryostatin‐1 had better performance in the water maze than untreated controls. Treated mice exhibited significantly shorter latencies and swimming distances to find the hidden platform, with no difference in their swimming speeds. The most profound effect was found in the early days of testing. The treated mice had performance nearly identical to that of the wild‐type controls. These data suggest that oral Bryostatin‐1 may be useful in treating cognitive decline associated with AD.This research was supported by a grant from the NIA and NIH (1R44AG034760‐01A1)

Purpose: Patients treated with radiotherapy for head-and-neck cancer invariably suffer its deleterious side effect, xerostomia. Salivary hypofunction ensuing from the irreversible destruction of glands is the most common and debilitating oral complication affecting patients undergoing regional radiotherapy. Given that the current management of xerostomia is palliative and ineffective, efforts are now directed toward preventive measures to preserve gland function. The human homolog of Tousled protein, TLK1B, facilitates chromatin remodeling at DNA repair sites and improves cell survival against ionizing radiation (IR). Therefore, we wanted to determine whether a direct transfer of TLK1B protein to rat salivary glands could protect against IR-induced salivary hypofunction.Methods: The cell-permeable TAT-TLK1B fusion protein was generated. Rat acinar cell line and rat salivary glands were pretreated with TAT peptide or TAT-TLK1B before IR. The acinar cell survival in vitro and salivary function in vivo were assessed after radiation.Results: We demonstrated that rat acinar cells transduced with TAT-TLK1B were more resistant to radiation (D-0 = 4.13 +/- 1.0 Gy; alpha/beta = 0 Gy) compared with cells transduced with the TAT peptide (D-0 = 4.91 +/- 1.0 Gy; alpha/beta = 20.2 Gy). Correspondingly, retroductal instillation of TAT-TLK1B in rat submandibular glands better preserved salivary flow after IR (89%) compared with animals pretreated with Opti-MEM or TAT peptide (31% and 39%, respectively; p < 0.01).Conclusions: The results demonstrate that a direct transfer of TLK1B protein to the salivary glands effectively attenuates radiation-mediated gland dysfunction. Prophylactic TLK1B-protein therapy could benefit patients undergoing radiotherapy for head-and-neck cancer. (C) 2012 Elsevier Inc.

There have been dramatic increases in the nonmedical use of prescription opioids, such as oxycodone and hydrocodone. While there has been significant research on the use of these drugs for short‐term analgesic use, much less is known about the consequences of chronic use. In this study we have investigated molecular biosignatures of chronic oxycodone treatment of adult rats. We have analyzed three brain regions: brainstem, nucleus accumbens and cortex. We observed that oxycodone activates ERK1/2, p38 and mTOR pathways in brainstem and nucleus accumbens suggesting pro‐survival and cytoprotective action. In agreement with these data, the level of phosphorylated 4E‐BP1 and eIF4E increased in brainstem and nucleus accumbens suggesting regulation of translation initiation rate in these tissues. Changes in the rate of translation may also indicate that oxycodone affects the spectrum of mRNAs translated. Polysomal analyses suggested translational down‐regulation of MOR‐1, Bcl‐2, and cFos mRNAs and up‐regulation of DOR mRNA by oxycodone in brainstem. Western blotting confirmed that levels of MOR‐1 and cFos proteins indeed decreased in brainstem lysates from oxycodone‐treated rats. Down‐expression of MOR‐1 maybe a marker of tolerance and dependence, while and upregulation of DOR following chronic oxycodone may be a marker for altered pain and analgesia sensitivity in these rats. Supported by Department of Emergency Medicine and Department of Pharmacology, Toxicology and Neuroscience, Louisiana State University Health Sciences Center; Shreveport.

Oxycodone is a prescription opioid that is widely used because of its substantial analgesic efficacy. However, it is accompanied by numerous side effects such as nausea, constipation, mioisis and respiratory depression, which can decrease patient compliance with treatment, affect quality of life and potentially lead to coma or death. These adverse effects are mediated by neurons in brain stem nuclei. Understanding changes in gene expression and signaling following chronic exposure will be helpful in developing therapeutic strategies to mitigate these effects. We have analyzed the effect of chronic oxycodone exposure on MAPK and mTOR as well as translational pathways in rat brain stem. We observed increase in phosphorylation of p38 and mTOR but not ERK1/2 kinases by oxycodone. Since p38 kinase is activated in response to cytokines or stress, our results suggest that oxycodone exposure triggers the cellular response to chronic stress. Analysis of translational regulation in rat brain stem revealed both stimulatory and inhibitory effects of chronic oxycodone exposure on various steps of translation. The possible mechanism of translational regulation of specific mRNAs by chronic oxycodone exposure in rat brain stem will be discussed. Supported by Department of Emergency Medicine and Department of Pharmacology, Toxicology and Neuroscience, Louisiana State University Health Sciences Center; Shreveport.

Frontotemporal lobar degeneration (FTLD) is a neurodegenerative disease that involves cognitive decline and dementia. To model the hippocampal neurodegeneration and memory-related behavioral impairment that occurs in FTLD and other tau and TDP-43 proteinopathy diseases, we used an adeno-associated virus serotype 9 (AAV9) vector to induce bilateral expression of either microtubule-associated protein tau or transactive response DNA binding protein 43 kDa (TDP-43) in adult rat dorsal hippocampus. Human wild-type forms of tau or TDP-43 were expressed. The vectors/doses were designed for moderate expression levels within neurons. Rats were evaluated for acquisition and retention in the Morris water task over 12 weeks after gene transfer. Neither vector altered acquisition performance compared to controls. In measurements of retention, there was impairment in the TDP-43 group. Histological examination revealed specific loss of dentate gyrus granule cells and concomitant gliosis proximal to the injection site in the TDP-43 group, with shrinkage of the dorsal hippocampus. Despite specific tau pathology, the tau gene transfer surprisingly did not cause obvious neuronal loss or behavioral impairment. The data demonstrate that TDP-43 produced mild behavioral impairment and hippocampal neurodegeneration in rats, whereas tau did not. The models could be of value for studying mechanisms of FTLD and other diseases with tau and TDP-43 pathology in the hippocampus including Alzheimer's disease, with relevance to early stage mild impairment.

Oxycodone, a semisynthetic opioid analgesic, is frequently prescribed for the management of pain. Side effects of nausea and emesis affect patient compliance and limit its therapeutic use. The present study established that an antinociceptive dose of oxycodone (15 mg/kg; oral) induces the pica response. We found sex differences in the temporal course of pica, with females having a longer duration. Opioid receptors mediated the pica response, as 1.0 mg/kg naloxone transiently attenuated and 2.0 mg/kg naloxone blocked pica. A κ-selective antagonist failed to block the response, suggesting mediation by μ opioid receptor. For further validation, we used the well established kaolin intake model to assess pica with the chemotherapeutic drug cisplatin as a positive control. Oxycodone and cisplatin significantly increased kaolin intake 4- to 7-fold, and the wet weight of stomach was elevated 2- to 3-fold. To examine the underlying neural circuitry, we investigated c-fos activation in the area postrema and nucleus of solitary tract (NTS). Oxycodone treatment significantly increased the number of c-fos-positive neurons in the area postrema and NTS compared with water controls. As expected, cisplatin also increased the number of c-fos-positive cells in these regions. In the area postrema, the oxycodone effect was greater than cisplatin, especially at 2 h. These results indicate that an antinociceptive dose of oxycodone is associated with the expression of pica, a pro-emetic response.

Improved spread of transduction in the central nervous system (CNS) was achieved from intravenous administration of adeno-associated virus serotype-9 (AAV9) to neonatal rats. Spinal lower motor neuron transduction efficiency was estimated to be 78% using the highest vector dose tested at a 12-week interval. The widespread expression could aid studying diseases that affect both the spinal cord and brain, such as amyotrophic lateral sclerosis (ALS). The protein most relevant to neuropathology in ALS is transactive response DNA-binding protein 43 (TDP-43). When expressed in rats, human wild-type TDP-43 rapidly produced symptoms germane to ALS including paralysis of the hindlimbs and muscle wasting, and mortality over 4 weeks that did not occur in controls. The hindlimb atrophy and weakness was evidenced by assessments of rotarod, rearing, overall locomotion, muscle mass, and histology. The muscle wasting suggested denervation, but there was only 14% loss of motor neurons in the TDP-43 rats. Tissues were negative for ubiquitinated, cytoplasmic TDP-43 pathology, suggesting that altering TDP-43's nuclear function was sufficient to cause the disease state. Other relevant pathology in the rats included microgliosis and degenerating neuronal perikarya positive for phospho-neurofilament. The expression pattern encompassed the distribution of neuro-pathology of ALS, and could provide a rapid, relevant screening assay for TDP-43 variants and other disease-related proteins.

PKMζ has a fundamental role in the retention of long‐term memories and synaptic plasticity. We examined the behavioral consequences of stress and the concomitant changes in PKMζ protein expression. Our results show that adolescent (38 day‐old) male rats given an acute stress significantly elevated corticosterone in blood sera, increased PKMζ protein expression within the hippocampus, and produced a translocation of the GluR2 subunit to the synaptic membrane. Immediately following an acute stress condition (45 min of elevated platform stress) PKMζ protein increased within the synaptic and cytosolic fractions. The GluR2 receptor subunit increased significantly in the synaptic fraction (p>.05). In contrast, seven days following acute stress PKMζ levels continued to be significantly elevated in the cytosolic fraction but not in the synaptic fraction compared to age matched, unstressed controls. Hippocampal slices made from rats immediately after acute stress show depressed levels of synaptic potentiation (long‐term potentiation; LTP) in area CA1 of the hippocampus, but increased levels of depression (long‐term depression; LTD) as compared to unstressed controls. These results showing an increase in PKMζ and the GluR2 subunit in the synaptic region are consistent with PKMζ induced trafficking of this receptor during synaptic plasticity and LTP.