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F P Zemlan

Publications and source records attributed to F P Zemlan.

At least 19 recordsLinked to original sources

The effect of amphetamine analogs on cleaved microtubule-associated protein-tau formation in the rat brain.

The present study quantified the cleaved form of the microtubule-associated protein tau (cleaved MAP-tau, C-tau), a previously demonstrated marker of CNS toxicity, following the administration of monoamine-depleting regimens of the psychostimulant drugs amphetamine (AMPH), methamphetamine (METH), +/-3,4-methylenedioxymethamphetamine (MDMA), or para-methoxyamphetamine (PMA) in an attempt to further characterize psychostimulant-induced toxicity. A dopamine (DA)-depleting regimen of AMPH produced an increase in C-tau immunoreactivity in the striatum, while a DA- and serotonin (5-HT)-depleting regimen of METH produced an increase in the number of C-tau immunoreactive cells in the striatum and CA2/CA3 and dentate gyrus regions of the hippocampus. MDMA and PMA, two psychostimulant drugs that produce selective 5-HT depletion in the striatum, had no effect on C-tau immunoreactivity in the striatum or hippocampus. Furthermore, 5,7-dihydroxytryptamine (5,7-DHT), an established 5-HT selective neurotoxin, did not produce an increase in C-tau immunoreactivity. Dual fluorescent immunocytochemistry with antibodies to glial fibrillary acidic protein (GFAP) and C-tau indicated that C-tau immunoreactivity was present in astrocytes, not neurons, suggesting that increased C-tau may be an alternative indicator of reactive gliosis. The present results are consistent with previous findings that the DA-depleting psychostimulants AMPH and METH produce reactive gliosis whereas the 5-HT-depleting drugs MDMA and PMA, as well as the known 5-HT selective neurotoxin 5,7-DHT, do not produce an appreciable glial response.

5,7-Dihydroxytryptamine↗

Treatment with trimethyltin promotes the formation of cleaved tau in the rat brain.

Trimethyltin (TMT) is a well-documented neurotoxin that affects primarily limbic system structures. Most previous studies have relied on histological approaches to examine TMT neurotoxicity, so the aim of this study was to employ the novel biomarker cleaved MAP-tau (C-tau) to assess TMT-induced CNS injury both quantitatively and qualitatively. Immunoblot studies indicated that cleaved MAP-tau proteins with molecular weights of 45-50 kD were present in the hippocampus of rats treated with TMT but not vehicle 21 days after treatment. Quantitative ELISA revealed that C-tau concentration in rats treated with TMT was greatest at 14 and 21 days in the piriform cortex and hippocampus, respectively; TMT did not significantly increase C-tau concentration in the mesencephalon. C-tau immunocytochemistry demonstrated the greatest TMT-induced damage in the hippocampus and piriform cortex. Additional studies utilizing dual immunocytochemistry revealed that C-tau-labeled cells were also glial fibrillary acidic protein-positive, leading to identification of these cells as astrocytes. Although the origin of C-tau in astrocytes of rats treated with TMT is currently unknown, increased C-tau concentration and the presence of C-tau positive cells in limbic system structures of TMT-treated rats further supports the view that C-tau is a reliable marker of CNS toxicity.

Animals↗

A single blind, placebo controlled, across groups dose escalation study of the safety, tolerability, pharmacokinetics and pharmacodynamics of the melatonin analog beta-methyl-6-chloromelatonin.

Clinical investigation of melatonin agonists has been hampered by side effects such as hypothermia, hypotension and bradycardia. The availability of a melatonin agonist devoid of these side effects would improve our understanding of the mechanisms by which melatonin agonists affect sleep. This study investigated the pharmacokinetics, pharmacodynamics and safety of the melatonin agonist beta-methyl-6-chloromelatonin at doses up to 100 mg in healthy volunteers. The design was a single blind, across subjects, placebo controlled, group wise dose escalation using doses of 20, 35, 50 and 100 mg beta-methyl-6-chloromelatonin. Eight subjects received one dose of study drug or placebo. Pharmacokinetic analysis showed a consistent Tmax across all doses with a mean of 1.12 +/- 0.11 hr for all groups (mean +/- SD). The half-life was also consistent across dose, with a mean of 1.04 +/- 0.04 hr. Maximum plasma concentrations increased with increasing dose with values of 44.83 +/- 29.79, 100.3 +/- 41.08, 79.84 +/- 26.36 and 410.3 +/- 129.4 ng/ml at doses of 20, 35, 50 and 100 mg, respectively. Area under the curve showed similar increases. No consistent changes in vital signs occurred as a function of dose or time after study drug. The incidence of all adverse events, the severity of the event or the event's relationship to treatment did not increase with higher doses of beta-methyl-6-chloromelatonin. Sleepiness was reported after all doses of beta-methyl-6-chloromelatonin. beta-methyl-6-chloromelatonin appears safe and well tolerated at doses up to 100 mg. These doses are not associated with hypothermia, bradycardia or hypotension. A melatonin agonist lacking these side effects should allow investigation of the direct soporific effects of melatonin agonists.

Adolescent↗

Methamphetamine enhances the cleavage of the cytoskeletal protein tau in the rat brain.

The view that methamphetamine is neurotoxic to dopaminergic and serotonergic axon terminals has been based largely on biochemical and histological studies. In the present study, methamphetamine-induced structural damage to axons was quantified using a sensitive sandwich enzyme-linked immunosorbent assay developed for the detection of the cleaved form of the cytoskeletal protein tau. The administration of a monoamine-depleting regimen of methamphetamine (4 x 10 mg/kg, i.p. every 2 hours for a total of four injections) produced a time-dependent increase in the concentration of cleaved tau in the striatum. Maximal concentrations of cleaved tau were detected 3 days following methamphetamine administration. Cleaved tau concentrations also were significantly elevated in the dorsal hippocampus and, to a lesser extent, in the prefrontal cortex of methamphetamine-treated rats. Maintenance of rats in a cold (4 degrees C) environment not only prevented the methamphetamine-induced depletion of striatal dopamine and serotonin but also prevented the methamphetamine-induced increase in striatal cleaved tau concentrations. The novel findings from this study are supportive of the view that methamphetamine produces acute structural damage to neurons that may lead to the long-term neurotoxic effects of repeated, high-dose administration of the drug and that cleaved tau reliably quantifies the time-dependent neurotoxic effects of methamphetamine.

Animals↗

Quantification and localization of kainic acid-induced neurotoxicity employing a new biomarker of cell death: cleaved microtubule-associated protein-tau (C-tau).

Previous studies of neuronal degeneration induced by the neurotoxin, kainic acid, employed silver stain techniques that are non-quantitative or ELISA measurement of the non-neuronal protein, glial fibrillary acidic protein. As previous studies employed biomarkers that were either non-quantitative or non-neuronal, the present study employed a new neuronally localized biomaker of neuronal damage, cleaved microtubule-associated protein (MAP)-tau (C-tau). The time course of kainate neurotoxicity was quantitatively determined in several brain regions in the present study employing a C-tau specific ELISA. Differences in ELISA determined regional brain levels of C-tau were compared with the density of somatodendritic C-tau labeling qualitatively determined in immunohistochemical anatomical mapping studies of kainic acid-treated animals. Immunoblot studies revealed that the C-tau antibodies employed in the present study were highly specific for proteolytic cleaved C-tau. Immunolabeling of 45 kD-50 kD C-tau proteins was observed only in brain samples from kainic acid-treated but not vehicle-treated rats. Time course studies revealed that C-tau levels determined by ELISA were maximal 3 days after kainic acid with C-tau levels increasing 26-fold in hippocampus, 16-fold in cortex and four-fold in both striatum and hypothalamus. These statistical differences in maximal C-tau levels observed in the ELISA studies were similar to differences qualitatively observed in C-tau immunohistochemical studies. C-tau immunohistochemistry revealed extensive damage in hippocampal regions CA1 and 3, moderate damage in several cortical regions and mild damage in striatum and hypothalamus. Similar cleavage of rat MAP-tau to C-tau has been reported after neuronal degeneration induced by neurotoxic doses of methamphetamine and neuronal degeneration resulting from bacterial meningitis. In humans, C-tau proteolysis has been demonstrated to be a reliable biomarker of neuronal damage in traumatic brain injury and stroke where cerebrospinal C-tau levels are correlated with patient clinical outcome. These data suggest that C-tau proteolysis may prove a reliable species independent biomarker of neuronal degeneration regardless of source of injury.

Animals↗

Discordant temporal patterns of S100beta and cleaved tau protein elevation after head injury: a pilot study.

There is considerable interest in S100beta protein as a potential marker that can be used to quantify central nervous system injury. However, increasing appreciation that S100beta may be produced by non-neural tissue (specifically adipocytes), has led to a search for more specific markers of brain injury. Recent interests have focused on a cleaved form of tau protein (c tauP) which is elevated in CSF from patients suffering traumatic brain injury. We have investigated whether levels in peripheral blood are a satisfactory alternative to provide an accessible marker of CNS injury severity. We measured levels of S100beta and c tauP in arterial blood from 20 patients with severe head injury. When compared with normal values S100beta was elevated 10-fold in the first 24 hours and c tauP was elevated at all time points, but showed a reversal of the temporal trend observed with S100beta. Patients with a poor outcome (GOS 1-3) had significantly higher S100beta levels on day one. Plasma c tauP levels did not correlate with outcome following head injury.

Adolescent↗

Serum cleaved Tau protein and neurobehavioral battery of tests as markers of brain injury in experimental bacterial meningitis.

Brain injury due to bacterial meningitis affects multiple areas of the brain with a heterogeneous distribution generating a challenge to assess severity. Tau proteins are microtubular binding proteins localized in the axonal compartment of neurons. Brain injury releases cleaved Tau proteins (C-tau) into the extracellular space where they are transported to the cerebral spinal fluid. We hypothesized that C-tau crosses the blood-brain barrier during inflammation and that it can be detected in serum. The correlation between serum C-tau levels and the extent of the meningitic insult was examined. Furthermore, we studied whether the use of a subset of neurobehavioral tasks can assess the extent of brain injury after meningitis. The tests were chosen primarily for their ability to detect deficits in the acoustic system, low brain, reflexive responding, as well as for impaired motor coordination and the higher brain functions of learning and memory. A rat model of group B streptococcal meningitis with variable severity was utilized. At five days after bacterial inoculation followed by antibiotic therapy neurobehavioral tests were performed and serum C-tau and histologic samples of the brain were obtained. Our study shows that during meningitis C-tau appears in serum and reflects the extent of neurologic damage. Neurobehavioral performance was altered after bacterial meningitis and could be correlated with histologic and biochemical markers of neurologic sequelae. We conclude that serum C-tau and a composite of neurobehavioral tests could become useful markers for assessing the severity of neurological damage in experimental bacterial meningitis.

Animals↗

Hypothermia as an adjunctive treatment for severe bacterial meningitis.

Brain injury due to bacterial meningitis results in a high mortality rate and significant neurologic sequelae in survivors. The objective of this study was to determine if the application of moderate hypothermia shortly after the administration of antibiotics would attenuate the inflammatory response and increase in intracranial pressure that occurs in meningitis. For this study we used a rabbit model of severe Group B streptococcal meningitis. The first component of this study evaluated the effects of hypothermia on blood-brain barrier function and markers of inflammation in meningitic animals. The second part of the study evaluated the effects of hypothermia on intracranial pressure, cerebral perfusion pressure and brain edema. This study demonstrates that the use of hypothermia preserves CSF/serum glucose ratio, decreases CSF protein and nitric oxide and attenuates myeloperoxidase activity in brain tissue. In the second part of this study we show a decrease in intracranial pressure, an improvement in cerebral perfusion pressure and a decrease in cerebral edema in hypothermic meningitic animals. We conclude that in the treatment of severe bacterial meningitis, the application of moderate hypothermia initiated shortly after antibiotic therapy improves short-term physiologic measures associated with brain injury.

Animals↗

Quantification of axonal damage in traumatic brain injury: affinity purification and characterization of cerebrospinal fluid tau proteins.

Diffuse axonal injury is a primary feature of head trauma and is one of the most frequent causes of mortality and morbidity. Diffuse axonal injury is microscopic in nature and difficult or impossible to detect with imaging techniques. The objective of the present study was to determine whether axonal injury in head trauma patients could be quantified by measuring levels of CSF tau proteins. Tau proteins are structural microtubule binding proteins primarily localized in the axonal compartment of neurons. Monoclonal antibodies recognizing the form of tau found in the CSF of head trauma patients were developed by differential CSF hybridoma screening using CSF from head trauma and control patients. Clones positive for head trauma CSF tau proteins were used to characterize this form of tau and for ELISA development. Using the developed ELISA, CSF tau levels were elevated >1,000-fold in head trauma patients (mean, 1,519 ng/ml of CSF) when compared with patients with multiple sclerosis (mean, 0.014 ng/ml of CSF; p < 0.001), normal pressure hydrocephalus (nondetectable CSF tau), neurologic controls (mean, 0.031 ng/ml of CSF; p < 0.001), or nonneurologic controls (nondetectable CSF tau; p < 0.001). In head trauma, a relationship between clinical improvement and decreased CSF tau levels was observed. These data suggest that CSF tau levels may prove a clinically useful assay for quantifying the axonal injury associated with head trauma and monitoring efficacy of neuroprotective agents. Affinity purification of CSF tau from head trauma patients indicated a uniform cleavage of approximately 18 kDa from all six tau isoforms, reducing their apparent molecular sizes to 30-50 kDa. These cleaved forms of CSF tau consisted of the interior portion of the tau sequence, including the microtubule binding domain, as judged by cyanogen bromide digestion. Consistent with these data, CSF cleaved tau bound taxol-polymerized microtubules, indicating a functionally intact microtubule binding domain. Furthermore, epitope mapping studies suggested that CSF cleaved tau proteins consist of the interior portion of the tau sequence with cleavage at both N and C terminals.

Alzheimer Disease↗

Identification of microtubule-associated protein tau isoforms in Alzheimer's paired helical filaments.

AD66 proteins derived from sodium dodecylsulfate (SDS) insoluble paired helical filaments (PHF) were isolated from Alzheimer's brain using a purification procedure developed previously in this laboratory, and characterized by immunologic and chemical cleavage methods. AD66 proteins were immunoreactive with antibodies that recognize the amino terminal, tubulin-binding, and carboxy terminal domains of microtubule-associated protein tau indicating the presence of the entire tau sequence in AD66 proteins. These proteins were reactive with antibody 423 that binds to PHF but not human adult tau. Immunologic and chemical cleavage studies indicated that only two of the six tau isoforms were present in these proteins. AD66 proteins were comprised of tau proteins containing only three tubulin binding domains with either a 29 amino acid insert or no amino terminal insert. For comparative purposes, SDS soluble PHF-tau (A68 proteins) was purified from Alzheimer's brains and normal adult tau purified from control brains. Antibody Alz-50 was immunoreactive with PHF-tau or normal tau regardless of alkaline phosphatase treatment while immunoreactivity was only observed with dephosphorylated AD66 proteins. A second phosphorylated epitope on AD66 proteins but not PHF-tau or normal tau proteins was demonstrated with antibody PHF9. These data suggest that AD66 proteins represent a more phosphorylated form of tau than PHF-tau or normal tau proteins. Two-dimensional gel electrophoresis demonstrated that AD66 proteins have higher apparent molecular weights and lower pI values than normal tau, differences possibly due to the greater phosphorylation observed in these proteins.

Adult↗

Monoclonal antibody PHF-9 recognizes phosphorylated serine 404 of tau protein and labels paired helical filaments.

Paired helical filaments (PHFs) purified from alzheimer's brain consist of hyperphosphorylated microtubule-associated protein tau. In PHF, phosphorylation occurs at ser/thr tau residues. Several of these ser/thr phosphorylation sites lie immediately C-terminal to the tau tubulin binding domain. The C-terminal ser396 to thr413 tau region contains two or more phosphorylated residues and eight possible ser/thr phosphorylation sites. Immunologic studies and mass spectroscopy have identified ser396 as one of the phosphorylation sites but identification of more C-terminal phosphorylated residues has been hampered by the lack of monoclonal antibodies (Mabs) that recognize defined epitopes in this region. We have raised Mabs against PHF purified from Alzheimer's brain. One of these Mabs, PHF-9, showed phosphorylation-dependent binding to purified PHF and recognized a phosphorylated epitope in the C-terminal portion of cyanogen bromide-digested PHF. Epitope mapping studies employing synthetic tau phosphopeptides indicated that PHF-9 labeled a 13-mer tau peptide phosphorylated at ser404 but not the corresponding non-phosphorylated peptide. PHF-9 demonstrated no immunoreactivity with a synthetic peptide phosphorylated at ser396 indicating that the PHF-9 epitope is C-terminal to ser396. In conclusion, the present study describes a Mab, PHF-9, which recognizes phosphorylated ser404 of tau independently of phosphorylated ser396 and indicates that tau ser404 is phosphorylated in PHF.

Alzheimer Disease↗

Velnacrine for the treatment of Alzheimer's disease: a double-blind, placebo-controlled trial. The Mentane Study Group.

The present study examines the safety and efficacy of the centrally acting cholinesterase inhibitor, velnacrine, in treating the cognitive symptoms of Alzheimer's disease. Seven hundred thirty-five patients with mild-to-severe Alzheimer's disease were treated in a double-blind, placebo-controlled study. Following the screen visit, patients were treated with velnacrine (10, 25, 50 and 75 mg t.i.d.) or placebo in a double-blind dose-ranging study to identify velnacrine-responsive patients and their best dose. Following placebo washout velnacrine responsive patients were randomly assigned to their best dose of velnacrine (N = 153) or placebo (N = 156) in a six week double-blind dose-replication study. Primary efficacy measures were the cognitive subscale of the Alzheimer's Disease Assessment Scale (ADAS) and the Physician's Clinical Global Impression of Change. Statistically significant improvement was observed in both primary efficacy measures in velnacrine-treated patients during the dose-replication study. Velnacrine patients scored better on the cognitive subscale of the ADAS than placebo patients (P < 0.001), with patients receiving the highest velnacrine dose averaging a 4.1-point improvement with respect to screen values. Clinical Global Impression of Change scores of velnacrine-treated patients were significantly improved at the end of the 6 weeks of treatment when compared to those of placebo patients (P < 0.05). The most common side effect was asymptomatic elevation in liver transaminase levels, which occurred among 29% of patients. These data suggest that velnacrine produces modest clinical improvement in a subset of patients with mild-to-severe Alzheimer's disease.

Adult↗

Double-blind placebo-controlled study of velnacrine in Alzheimer's disease.

The present study assessed the safety and efficacy of the cholinesterase inhibitor, velnacrine, for treating the cognitive symptoms of Alzheimer's disease. Patients (N = 236) meeting NINCDS-ADRDA criteria for Alzheimer's disease entered a double-blind, placebo-controlled dose-ranging protocol (30, 75, 150, 225 mg/day each for one week) to identify velnacrine responders (> or = four point improvement on the cognitive subscale of the Alzheimer's Disease Assessment Scale [ADAScog]). After a two week drug washout, velnacrine responders were randomly assigned to their best velnacrine dose or placebo in a six week dose-replication protocol employing the ADAScog and the Clinical Global Improvement scale as primary outcome measures. During dose-replication, intent-to-treat analysis revealed that velnacrine patients scored significantly better than placebo patients on the ADAScog after two (p < 0.004), four (p < 0.025) and six (p < 0.001) weeks of treatment. No significant treatment effect on Clinical Global Improvement scores was observed. The primary adverse event was an asymptomatic elevation of liver transaminases found among 28% of the 236 treated patients. Cholinergic side effects including diarrhea (14%), nausea (11%) and vomiting (5%) were observed and 8% of patients experienced skin rash. The present study identified a subgroup of Alzheimer's patients who demonstrated a significant, but modest, improvement during velnacrine treatment on structured cognitive testing.

Aged↗

A treatment and withdrawal trial of besipirdine in Alzheimer disease.

Besipirdine hydrochloride (HP 749) is an indole-substituted analog of 4-aminopyridine. Besipirdine enhances both cholinergic and adrenergic neurotransmission in the central nervous system. The present study examined the efficacy and tolerability of two doses of besipirdine (5 and 20 mg b.i.d.) in 275 patients with Alzheimer disease during 3 months of treatment and for 3 months after withdrawal of treatment. Assessment after withdrawal of treatment was used in an effort to distinguish persistent efficacy attributable to a neuroprotective mechanism from reversible symptomatic efficacy. Besipirdine was generally well tolerated. The level of performance on the cognitive subscale of the Alzheimer Disease Assessment Scale (ADAS-Cog) was sustained during 3 months of treatment with besipirdine, whereas some deterioration in the performance of patients treated with placebo was observed over the same period. The small difference between active and placebo treatment groups approached, but did not reach statistical significance in the primary intent-to-treat analysis (p = 0.067); analysis of patients who completed all assessments was supportive (p = 0.031). Global ratings using the Clinician Interview-Based Impression of Change did not detect a besipirdine treatment benefit, possibly because of an adverse effect on mood and behavior in some patients. A high ratio of adrenergic to cholinergic potency may have resulted in the adverse effects of besipirdine and hence its failure to support the hypothesis that multiple neurotransmitter treatment may be more efficacious than monotherapy. The efficacy apparent on the ADAS-Cog after 3 months of treatment did not persist 3 months after withdrawal of treatment, suggesting that the benefit was symptomatic. This study provides a practical example of the use of treatment withdrawal assessment to distinguish neuroprotective from symptomatic efficacy.

Aged↗

Alzheimer's paired helical filaments: amyloid precursor protein epitope mapping.

Paired helical filaments (PHF) were electrophoretically purified and solubilized from Alzheimer's neurofibrillary tangles and consisted of a primary 66 kDa protein on SDS-PAGE analysis. A panel of antibodies raised against restricted regions of the beta-amyloid precursor protein (APP) were employed for epitope mapping studies of this 66 kDa PHF protein. Western blot studies revealed that C-terminal APP antibodies were immunoreactive with the 66 kDa PHF protein. Further analysis revealed that only antisera raised against peptides that include the beta/A4-amyloid region within the C-terminal portion of APP were immunoreactive with PHF proteins. These data complement previous immunocytochemical studies which indicated that C-terminal APP antibodies preferentially label PHF-containing neurofibrillary tangles in Alzheimer's brain. The present data suggest a similarity of secondary or tertiary structure between beta/A4-amyloid and PHF which accounts for the cross-reactivity of beta/A4-amyloid antibodies with PHF proteins.

Alzheimer Disease↗

5-HT1A receptors mediate the effect of the bulbospinal serotonin system on spinal dorsal horn nociceptive neurons.

The present study examined whether the effect of stimulation of the nucleus raphe magnus (NRM) is mediated by spinal cord dorsal horn serotonin1A (5-HT1A) receptors in the rat. This hypothesis predicts that nociceptive dorsal horn units inhibited by NRM stimulation or iontophoretic 5-HT application would also be inhibited by iontophoresis of the selective 5-HT1A agonists 8-hydroxy-2-(di-n-propylamino)tetralin (8-OH-DPAT) and buspirone. A total of 78 dorsal horn wide-dynamic-range neurons were recorded. Overall, 62% of the cells tested (48/78) were responsive to electrical stimulation of the NRM with the predominant response being inhibitory (38/48; 79%). Fifty-eight cells were tested for their response to both NRM stimulation and 8-OH-DPAT iontophoresis: 20/58 cells were inhibited by NRM stimulation and 50% of the cells inhibited by NRM stimulation were also inhibited by 8-OH-DPAT. Fifty-two cells were tested for their response to both NRM stimulation and buspirone iontophoresis: 14/52 cells were inhibited by NRM stimulation with 9/14 similarly inhibited by buspirone. To examine whether exogenously applied serotonin produced an effect through 5-HT1A receptors, the effect of both 5-HT and 8-OH-DPAT iontophoresis was tested on 57 dorsal horn neurons. The majority of cells (25/57) were inhibited by 5-HT application; 15/25 were similarly inhibited by 8-OH-DPAT. The response of 48 dorsal horn cells to 5-HT and buspirone iontophoresis was compared. Forty-four percent (21/48) of the cells were inhibited by 5-HT; 16/21 were also inhibited by buspirone.(ABSTRACT TRUNCATED AT 250 WORDS)

8-Hydroxy-2-(di-n-propylamino)tetralin↗

Role of spinal serotonin1 receptor subtypes in thermally and mechanically elicited nociceptive reflexes.

The ability of 5-HT1A and 5-HT1B agonists to alter a spinal animal's nociceptive threshold was examined using two analgesiometric tests. In the spinal withdrawal reflex test, administration of the selective 5-HT1A agonists ipsapirone, gepirone and PAPP resulted in significant dose-dependent increases in receptive field (RF) area for withdrawal reflexes when compared to predrug baseline values, indicating an increase in nociceptive sensitivity. The average overall percent maximal increase in RF area following administration of 5-HT1A selective compounds was: 80 +/- 16% for the ventroflexion reflex, 90 +/- 6% for the dorsiflexion reflex and 87 +/- 8% for the lateral flexion reflex. Similar to the effects noted with 5-HT1A agonists, administration of 5-HT1B agonists RU24969, mCPP and TFMPP resulted in a hyperalgesic response with an overall percent maximal increase of 43 +/- 6% for the ventroflexion reflex, 51 +/- 6% for the dorsiflexion reflex and 38 +/- 9% for the lateral flexion reflex. In the tail-flick analgesiometric test, administration of the 5-HT1A agonists 8-OH-DPAT and ipsapirone and the 5-HT1B agonists RU24969 and mCPP resulted in a significant dose-dependent increase in tail-flick latencies when compared to predrug baseline values, indicating a decrease in nociceptive sensitivity to noxious thermal stimuli. No differences in magnitude of the effect of the two receptor subtypes were found, indicating that stimulation of either 5-HT1A or 5-HT1B receptors was equipotent in producing the antinociceptive tail-flick response.(ABSTRACT TRUNCATED AT 250 WORDS)

8-Hydroxy-2-(di-n-propylamino)tetralin↗

A new scale for assessing behavioral agitation in dementia.

The primary purpose of the present study was to develop a reliable and valid rating instrument for assessing treatment efficacy for behavioral problems in the cognitively impaired elderly. The Behavioral and Emotional Activities Manifested in Dementia (BEAM-D) Scale was developed for the operational assessment of troublesome and disruptive behaviors in dementia. Each behavioral category of the BEAM-D was clinically considered to be a significant deviation from normative behavior for the geriatric dementia patient. The reliability and validity of the BEAM-D was assessed in a group of 45 patients diagnosed with primary degenerative dementia. The mean interrater reliability of BEAM-D items was 0.90. Concurrent validity was established by comparison with currently used rating scales, the Brief Psychiatric Rating Scale (BPRS) and the Sandoz Clinical Assessment-Geriatric (SCAG). Stepwise regression analysis revealed that the items of the BEAM-D had a strong relationship with conceptually similar behavioral dimensions on the BPRS and SCAG.

Aged↗