Urethral sphincter innervation and clitoral blood flow after the transobturator (TOT) approach

INTRODUCTION AND HYPOTHESIS

The aim of the study was to exclude neurovascular damage due to prosthetic mini-invasive surgery using transobturator tape (TOT) by pre- and postoperative electromyography (EMG) of the striated urethral sphincter and a color Doppler ultrasonography evaluation of clitoral blood flow.

METHODS

A total of 25 women affected by clinical stress urinary incontinence (SUI) were enrolled. After undergoing urodynamic assessment, pelvic organ prolapse quantification, urine culture, Q-tip test, and stress test, each subject underwent color Doppler ultrasonography to record clitoral blood flow and EMG of the urethral sphincter with a needle electrode inserted through the mucosa into the muscle tissue before surgery. A single urogynecologist performed the TOT surgical technique for the treatment of all patients. Urogynecologic examination, EMG, and color Doppler ultrasound follow-up were performed at 1 and 6 months after surgery.

RESULTS

At the urogynecologic examination performed 1 and 6 months after the TOT approach the stress test was negative, urethral hypermobility was reduced, and sling exposure was not observed for each patient. There was no statistically significant difference in electromyographic values (p > 0.05) in both the follow-ups with regard to baseline values. Pulsatility index (PI), resistance index (RI), and peak systolic velocity (PSV) values increased during the first follow-up (p < 0.01); PI and RI values increased during the second follow-up with respect to baseline values (p < 0.01)

CONCLUSIONS

TOT prosthesis surgery, avoiding denervation and devascularization of pelvic structures, does not damage the urethral sphincter.

Trazodone therapy of the post-stroke depression

The incidence of depression following a hemispheric stroke ranges from 25 to 60%. The benefit of antidepressant therapy on the outcome of rehabilitation in the subacute post-stroke phase is well known. We studied subjects both with and without evidence of depression, as indicated by any one of three criteria: (i) Clinical diagnosis of depression, (ii) Abnormal Zung-depression score. (iii) Abnormal dexamethasone suppression test (DST). Patients in a stroke rehabilitation program (22) were randomized to receive either placebo or 300 mg/day trazodone-HCl, beginning 30 days after the stroke. Patients with either a clinical diagnosis of depression or abnormal Zung depression scores showed a consistent trend towards greater improvement in Barthel activities of daily living (ADL) scores, with antidepressant therapy, as compared to patients receiving placebo. An abnormal DST was associated with significant improvement in the ADL scores in subjects receiving trazodone, i.e., in post-stroke depression such a treatment seems to be beneficial.

Psychotic complications of long term levodopa treatment of Parkinson's disease

Psychotic symptoms such as hallucinations, delusions and confusion are well known side-effects of levodopa (LD) therapy of Parkinson's disease (PD), even if there is much confusion regarding the variability of the psychotic manifestations. We studied 18 patients clinically treated with LD associated with an inhibitor of peripheral aminoacid decarboxylase (DI). Daily dosage of LD ranged between 250 and 1750 mg; the mean age of patients was 72.7 years; the age at the onset of the disease was 63.3 and duration of the disease 8.4 years. In all patients any possible etiology of Parkinsonism were excluded. Brain CT scan excluded focal lesions in all cases. Psychotic complications were seen in 8 patients: using DSM-III-R-criteria, the various LD-induced psychotic states can be classified in two groups: simple (including or hallucinations with preserved insight) and complex ones (including chronic confusion without preserved insight). Patients with complex symptoms were younger at the onset of the disease and they developed these symptoms later, and these patients were also more susceptible to dyskinesias developed before psychotic complications.

Pregabalin in the treatment of chronic pain: an overview

Chronic 'pathological' pain is sustained by mechanisms of peripheral and central sensitization, which are being increasingly investigated at the molecular and cellular levels. The molecular determinants of nociceptive sensitization are natural targets for potential analgesic drugs used in the treatment of different forms of pain. Most of these determinants are common to all forms of chronic pain, and it is therefore not surprising that drugs specifically targeted for the treatment of neuropathic pain are effective in relieving nociceptive inflammatory pain and vice versa. The molecular mechanisms of sensitization that occur in peripheral nociceptors and the dorsal horns of the spinal cord are putative targets for context-dependent drugs, i.e. drugs that are able to discriminate between 'normal' and 'pathological' pain transmission. Among these, pregabalin and gabapentin bind to the alpha(2)delta subunit of voltage-sensitive Ca2+ channels, which sustain the enhanced release of pain transmitters at the synapses between primary afferent fibres and second-order sensory neurons under conditions of chronic pain. Pregabalin in particular represents a remarkable example of a context-dependent analgesic drug that acts at a critical step of nociceptive sensitization. Preclinical and clinical data suggest that pregabalin is more than a structural and functional analogue of gabapentin and may be effective in the treatment of nociceptive inflammatory pain that is resistant to gabapentin.

Blink reflex abnormalities in children with Tourette syndrome

Tourette syndrome (TS) is a common disorder which typically occurs during childhood or early adolescence. There is no definitive diagnostic test for TS. The objective of this study was to demonstrate whether neurophysiological abnormalities of the blink reflex can be observed in children with TS. We enrolled 15 children with TS, diagnosed according to DSM IV Diagnostic Criteria, and 15 controls. The blink reflex was elicited by stimulating the supraorbital nerve in order to measure the early response (R1), homolateral and contralateral R2 (late) responses, amplitude of R1 and duration of R2. The mean duration of R2 was significantly longer in TS patients than in the controls (P < 0.001, Student's t-test). An abnormal pattern of the blink reflex can be, even in childhood, an early neurophysiologic marker of TS, which is not related to the duration of TS or to the age of onset.

Dopaminergic drugs may counteract behavioral and biochemical changes induced by models of brain injury

The dopaminergic drugs, bromocriptine, cabergoline, dihydroergocryptine, pergolide and ropinirole were injected subcutaneously (s.c.) at the dose of 0.1, 0.5 and 1 mg/kg/day for 7 days into male rats of the Sprague-Dawley strain. The drug pre-treatment reverted amnesia induced in rats by hypobaric hypopxia and tested in active and passive avoidance tasks. A restoration of memory retention, as assessed in a step-through passive avoidance task, was found in animals with a 2-month brain occlusive ischemia and exposed to dopaminergic drugs for 7 days. For behavioral effects in both active and passive avoidance tests in both experimental models, the rank of relative potency was ropirinole>bromocriptine=cabergoline>pergolide>dihydroergocryptine. Spontaneous ambulation of animals with brain occlusive ischemia was increased by the higher doses of drugs. All dopaminergic drugs reduced kainate mortality rate. The rank of relative potency for this effect was ropirinole=bromocriptine=cabergoline>pergolide=dihydroergocryptine. However, no change was found in other seizure parameters (latency to first convulsion and total number of convulsions) after drug treatment. A biochemical analysis of glutathione redox index (glutathione reduced/glutathione oxidized ratio) in discrete brain areas revealed that exposure to dopaminergic drugs increased this parameter in frontal cortex, striatum and hippocampus of animals subject to hypobaric hypoxia and brain occlusive ischemia. For this effect, the relative potency rank was ropirinole>bromocriptine=cabergoline>>pergolide=dihydroergocryptine. These behavioral and biochemical findings suggest that dopaminergic drugs may counteract either behavioral or biochemical changes induced by experimental models of brain injury. This activity was found after protective activity (as found in animals pre-treated with these drugs and exposed to hypobaric hypoxia) or reversal of brain injury (as found in animals treated after 2-month occlusive brain ischemia). Their neuroprotective activity probably involves the reduction/oxidation balance of the glutathione system in the brain.

Progressive supranuclear palsy: A systematic review

The progressive supranuclear palsy (PSP) is a rapidly progressing degenerative disease belonging to the family of tauophaties, characterized by the involvement of both cortical and subcortical structures. Although the pathogenesis of PSP is still uncertain, genetic, biochemical, and immunohistochemical studies have been performed and are reviewed here. Genetic factors, oxidative damage, neurotoxins, and environmental factors contribute to tau deposition in the cerebral areas involved in PSP. Symptoms originate from the ensuing dysfunction of dopaminergic, GABAergic, cholinergic, and noradrenergic pathways. Recent advances in neuroradiological and instrumental examinations facilitate the diagnosis and have gained new insights into the pathophysiology of PSP, although the primary cause of the disease is unknown and disease-modifying drugs are not yet available.

Different clinical and evolutional patterns in late idiopathic and vascular parkinsonism

OBJECTIVE

The aim of this study was to examine the clinical picture of Parkinson's disease (PD) and vascular parkinsonism (VP) in the elderly, in an attempt to differentiate the clinical history, symptoms, signs and response to therapy.

MATERIAL AND METHODS

Thirty-two elderly patients with late onset PD and 45 with VP were enrolled and the clinical features of two groups were compared. All patients underwent brain MRI and were scored using the Unified Parkinson's Disease Rating Scales (UPDRS) -II, -III.

RESULTS

Patients with PD had a younger age at onset and a longer duration of the disease as compared to patients with VP. Nearly all PD patients showed a good response to levodopa therapy, while only 29% of patients with VP were responsive to levodopa treatment. Vascular risk factors as well as postural tremor, gait disorders and pyramidal signs with lower body predominance, were more frequent in patients with VP. Ninety-three % of PD patients had normal MRI, whereas all patients with VP had cerebral vascular lesions. UPDRS-II, -III scores at baseline were higher in VP than in PD patients and their increases throughout the follow-up period were more marked in VP than in PD patients.

CONCLUSIONS

Clinical history, symptoms, signs, response to therapy, and brain imaging help to differentiate PD and VP as two clinical entities with different clinical, prognostic and therapeutic implications, even if the coexistence of PD and a cerebral vascular disease in elderly patients is not infrequent and can make the diagnosis difficult.

[Gilles de la Tourette's syndrome: a systematic review]

Gilles de la Tourette's syndrome is more frequent than once believed. This syndrome is a chronic disorder whose long term outcome is generally favourable, characterized by a fluctuating course. The etiopathogenesis of Gilles de la Tourette's syndrome has not been ascertained, although the frontal-subcortical neural pathways seem to be involved. This extrapyramidal syndrome is frequently associated with attention-deficit/hyperactivity disorder, obsessive-compulsive disorder, and behaviour problems. A correct diagnosis is the first step for a proper management of this disorder, which makes use of behavioural and pharmacological interventions.

Dementia with Lewy bodies: a review

The dementia with Lewy bodies (DLB) is the second major type of senile, degenerative dementia, after the Alzheimer disease (AD). It is characterized by the presence of cytoplasmic inclusions of alpha-synuclein in the cerebral cortex and in the nuclei of the brain stem. DLB patients frequently have complex visual hallucinations, depressive symptoms, Parkinsonian manifestations and cognitive deficits, showing important associations with the Parkinson disease and the AD. The DLB should be differentiated from atypical Parkinsonisms, but the differential diagnosis often remains difficult and unsafe. Clinical and neuropathological findings, as well as neuroimaging are valuable tools in establishing specific diagnosis of DLB. Acetylcholinesterase inhibitors, dopamine-agonists, benzodiazepines of short or medium half-life, and antidepressants may be useful in the treatment of DLB, depending on the dominant symptoms of the given patients.

Riluzole restores motor activity in rats with post-traumatic peripheral neuropathy

Riluzole is a presynaptic inhibitor of glutamate release with neuroprotective properties. In order to evaluate the effects of riluzole on motor activity in post-traumatic peripheral neuropathy (PTPN), the sciatic nerve of Wistar male rats was exposed monolaterally and subjected to crushing for one min by a surgical forceps. Animals received an intraperitoneal treatment with riluzole (2, 4 or 8 mg/kg per day), diclofenac (5, 10 or 20 mg/kg) or with vehicle for 3 days. Motor activity and coordination was evaluated in a circular open field and in the rotorod test. The treatment with riluzole stimulated ambulation in PTPN rats and improved their motor performance and coordination. The effect of treatment with riluzole on locomotor activity was greater than that of treatment with diclofenac and was dose-dependent. Furthermore, in contrast to vehicle- and diclofenac-treated rats, animals treated with riluzole showed a long-lasting improvement of locomotor activity as it was assessed 7 days after the end of treatment. These findings suggest that riluzole may improve motor performance in PTPN, and this does not depend on its antinociceptive activity. Its neuroprotective properties are possibly involved in this effect.

An increased expression of the mGlu5 receptor protein following LTP induction at the perforant path-dentate gyrus synapse in freely moving rats

The involvement of metabotropic glutamate (mGlu) receptors in the induction of long-term potentiation (LTP) in vivo has been consistently documented. We have investigated whether LTP induction in the dentate gyrus of rats leads to changes in expression of mGlu2/3 or -5 receptor subtypes in the hippocampus. LTP was induced at the medial perforant path-dentate gyrus synapses, and mGlu receptor expression was examined by Western blot or in situ hybridization. An up-regulation of mGlu5 receptors was observed in the hippocampus both 24 and 48 h following LTP induction. This effect was restricted to the dentate gyrus and CA1 region, whereas no changes in mGlu5 receptor protein (but an increase in mRNA levels) were observed in the CA3 region. The increased expression of mGlu5 receptors was directly related to the induction of LTP, because it was not observed when tetanic stimulation was carried out in animals treated with the NMDA receptor antagonist, 2-amino-5-phosphonopentanoate (AP5). Western blot analysis also showed a reduced expression of mGlu2/3 receptors in the whole hippocampus 24 h after LTP induction, indicating that the increased expression of mGlu5 receptors was specific. These data suggest that an up-regulation of mGlu5 receptors is a component of the plastic changes that follow the induction of LTP at the perforant path-dentate gyrus synapse.

Morphological and biochemical evidence that apomorphine rescues striatal dopamine terminals and prevents methamphetamine toxicity

Apomorphine, given by a single injection, repeated injections, or by continuous infusion, was tested for neuroprotective effects in mice administered methamphetamine or N-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) in order to induce striatal dopamine (DA) depletion. In the first part of the study, the DA agonist (R)-apomorphine was administered at various doses (1, 5, and 10 mg/kg), 15 min before methamphetamine (5 mg/kg x 3, 2 h apart). Mice were sacrificed 5 days later. In the second part, apomorphine was administered either continuously by subcutaneous minipump (cumulative daily dose of 0.5, 1, and 3.15 mg/kg), or as single, repeated daily injections (up to 5 mg/kg) starting 40 h after an acute administration of MPTP (30 mg/kg). Mice were sacrificed at different time intervals (up to 1 month) following MPTP injection. In all the animals, the integrity of striatal DA terminals was evaluated by measuring striatal DA levels and TH immunohistochemistry. Apomorphine dose-dependently prevented methamphetamine toxicity. These effects were neither due to a decrease in the amount of striatal methamphetamine nor to the hypothermia, and they were not reversed by the DA antagonist haloperidol. Moreover, chronic, continuous (but not pulsatile) administration of apomorphine rescued damaged striatal dopaminergic terminals. These findings confirm a protective effect of apomorphine that also consists of a neurorescue of damaged striatal DA terminals. This suggests a new hypothesis about the long-term benefits observed during continuous apomorphine administration in Parkinson's disease patients.

Behavioral and neurochemical effects of dopaminergic drugs in models of brain injury

The dopaminergic drugs, ropinirole and dihydroergocryptine (DHECP) were injected subcutaneously (s.c.) at doses of 0.5 and 1 mg/kg/day for 7 days into male rats of the Sprague-Dawley strain. The drug pretreatment reverted amnesia induced in rats by hypobaric hypopxia and tested in active and passive avoidance tasks. Furthermore, a partial restoration of memory retention was found in animals with a 2-month brain occlusive ischemia induced by manipulation of the four major arteries of the brain. No major changes were found in spontaneous motor activity, but drug treatment increased ambulation of animals subjected to acute or chronic experimental manipulation. In a model of kainate-induced epilepsy, ropinirole or DHECP did not affect seizure parameters, but reduced mortality rate. At the end of behavioral procedures, in all animals subjected to hypobaric hypoxia or to brain occlusive ischemia glutathione redox index (glutathione reduced/glutathione oxidized ratio) was measured in the frontal cortex, striatum and hippocampus. It was found that experimental models of brain injury were followed by a decrease of reduced glutathione content in all brain areas. The glutathione redox index was augmented by ropinirole or DHECP treatment in all brain areas. These behavioral and neurochemical findings suggest that ropinirole and DHECP may exert either protective activity (as found in animals pretreated with these drugs and exposed to hypobaric hypoxia) or reversal of brain injury (as found in animals treated after two-month occlusive brain ischemia). Thus, both drugs may be studied as therapeutic agents in brain injuries of various origin.

Efficacy and safety of fixed-dose oral sildenafil in the treatment of sexual dysfunction in depressed patients with idiopathic Parkinson's disease

OBJECTIVE AND METHODS

The efficacy and safety of oral Sildenafil, a potent inhibitor of phosphodiesterase type 5, were evaluated in depressed men with idiopathic Parkinson's disease and erectile dysfunction. Thirty-three men were enrolled in a 4-month prospective, open-label, fixed-dose study, and received 50mg of Sildenafil in the home setting approximately 1 hour before sexual activity, not more than once daily. Efficacy was determined by responses to question 3 (ability to achieve an erection) and question 4 (ability to maintain an erection) of the 15-item International Index of Erectile Function (IIEF). Other measures of efficacy included the five sexual function domains of IIEF, a global efficacy question, the Beck Depression Inventory (BDI) and the Hamilton Depression Rating Scale-21 (HDRS-21).

RESULTS

At the end of the study, improved erections were reported by 84.8% of patients. Sildenafil significantly increased patients' ability to achieve and maintain erections. Significant improvements were also observed in the IIEF domains for erectile function, orgasmic function, intercourse satisfaction and overall sexual satisfaction. BDI and HDRS scores improved from baseline to the end of the study. A clear improvement of depressive symptoms was observed in 75% of patients. Sildenafil was well tolerated in all the patients.

CONCLUSIONS

Treatment with oral Sildenafil improves erectile function and, indirectly, depressive symptoms in patients with idiopathic Parkinson's disease stages 1-3, and is well tolerated.

Autoimmune thyroiditis and acquired demyelinating polyradiculoneuropathy

Guillain-Barrè syndrome (GBS) and Miller-Fisher syndrome (MFS) are variant forms of acquired demyelinating polyradiculoneuropathy. Their concurrence with immune disorders of the thyroid is infrequent. We report on a 7.5-year-old girl in whom a subclinical thyroiditis was concurrently detected to GBS and a 70-year-old woman with Hashimoto's thyroiditis (HT) who had recurrent MFS. Even though autoimmune thyroiditis is associated with many autoimmune disorders more often than would be expected by chance alone, its concurrence with immune disorders of the peripheral nerve is less frequently reported. The calculated coincidental concurrence of acquired demyelinating polyradiculoneuropathy (in both variants, MFS and GBS) and autoimmune thyroiditis (as in the present cases) was extremely low (0.0004%), thus suggesting common pathogenic mediators.

Neuropsychiatric effects and type of IFN-alpha in chronic hepatitis C

Chronic hepatitis is often associated with neuropsychiatric disorders. Interferon (IFN) is the drug most widely used to treat this disease, and its side effects, such as depression, often involve the central nervous system (CNS). Symptoms include a slowing down of psychomotor functions, loss of interest, frontal lobe dysfunction, parkinsonism, and delirium. The occurrence of these complications calls for dropping out of IFN treatment or for a significant dose reduction and administration of antidepressants. Efficacy and side effects vary on the basis of the IFN type employed. The aim of our study was to evaluate if the frequency, form, and degree of depression induced are related to the type of IFN employed. We studied 96 patients with chronic hepatitis C. Our study series was divided into four groups according to the type of IFN-alpha administered. Depression degree was clinically evaluated using the Hamilton Depression Rating Scale (HAM-D). All patients were tested before treatment and 1, 3, and 6 months (15 days after the end of treatment) later. Our results showed that the type of IFN used seemed to influence the depression onset rate, with the leukocyte type inducing the lowest level of depression. However, when a number of symptoms associated with the depression were considered, the results of other types of IFN-alpha were found to be better. Use of the most suitable type of IFN-alpha could thus lead to more personalized treatment, with fewer side effects. The type of IFN used seems to influence the psychological side effects and the adaptation rate to therapy. It would be appropriate to choose the type of IFN on the basis of a neuropsychiatric assessment carried out before treatment.

Interferon alpha-induced depression in chronic hepatitis C patients: comparison between different types of interferon alpha

IFN alpha treatment is able to produce dose-related side effects, such as depression, in the central nervous system. We assessed the effects on depression of four different types of IFN alpha (recombinant IFN alpha 2a, recombinant IFN alpha 2b, lymphoblastoid IFN alpha, leukocyte IFN alpha), administered at the same doses in four homogeneous groups of chronic hepatitis C patients (96 patients; 24 patients for each group). A group of 18 untreated hepatitis C patients was considered as a control group. Depression was measured using Zung's self-rating depression scale (SDS scale) before starting IFN alpha therapy and at the 1st, 3rd and 6th month of treatment. In all patients evaluated, mean SDS values increased from mild to moderate depression, but never attained severe depression (SDS > 70). More elevated SDS values were observed in the 1st month of treatment, with a progressive decrease during the end points above-mentioned. The recombinant IFN alpha 2a and lymphoblastoid IFN alpha arms presented higher SDS mean scores compared to the recombinant IFN alpha 2b and leukocyte IFN alpha arm. Only in the leukocyte IFN alpha arm SDS values returned to basal values at the 6-month end point. Leukocyte IFN alpha seemed to present a more elevated tolerability than other IFN alpha types available for clinical practice. A very careful selection of hepatitis C patients is required before starting IFN alpha therapy.

Nicergoline facilitates vestibular compensation in aged male rats with unilateral labyrinthectomy

The ergoline derivatives, nicergoline (NIC) or dihydroergocristine (DHE) were administered at various doses (0.1, 0.5 and 1 mg/kg) to aged male rats subjected to labyrinth unilateral lesion (LBX). The nystagmus rate appeared to be lower in animals treated with DHE or NIC 1mg/kg than in saline-injected rats, when observed on day 1 and 2 after operation. The number of falls in the rotorod test of LBX animals was decreased by NIC 0.5 or 1 mg/kg at all observation times. This parameter was affected by DHE only at the higher dose. These results suggest that NIC facilitates vestibular compensation of LBX rats. DHE appeared to be less potent in this respect. Since both drugs act on central dopaminergic neurotransmission, it is possible that this neurotransmission may be involved in their mechanism of action.

Modulatory action of noradrenergic system on spinal motoneurons in humans

Previous findings in animals demonstrated that the noradrenergic coeruleospinal system exerts a tonic facilitation on spinal reflexes and that activation of alpha2-autoinhibitory receptors can be responsible for a disfacilitation of the spinal activity. To investigate this issue further, we examined whether this system is also involved in descending facilitatory control of spinal motoneurons in healthy humans. The H-reflex technique was utilized to assay the motoneuronal excitability. The ratio between the maximal reflex response (H) and maximal direct response (M) was determined in each subject and was calculated at 10 min intervals before and after i.v. administration of the alpha2-agonist clonidine (0.5 microg/kg). In all subjects a marked decrease of the H/M ratio, due to depression of the H response, occurred 10 min following the clonidine injection and reached its maximum within 30 min. No significant changes of blood pressure values were provoked by drug injections. These results suggest that an autoinhibitory action may be induced by alpha2-receptor activation of locus coeruleus neurons in humans, and that this device may serve as a mechanism for a myotonolytic action on spinal motoneurons.

Tacrine treatment of Alzheimer's disease: many expectations, few certainties

Quality of life and behavioral functions are severely reduced in patients affected by Alzheimer's disease (AD). Among the drugs employed in the treatment of this invalidating degenerative dementia, tacrine (THA) seemed to play a possible therapeutic role. Our study was aimed to evaluate the efficacy of THA in the treatment of AD, performing a comparison with lecithin and/or placebo treatment. Five randomized controlled trials on tacrine versus lecithin and/or placebo treatment were randomly selected. Mantel-Haenszel-Peto method was applied. Patients treated with tacrine achieved better results than control subjects (overall OR = 2.34; 95% CI 1.42-3.85); but long-term treatment with tacrine was not significantly more efficacious than placebo. Statistical significance in favor of THA versus other drugs employed was obtained in MMSE and ADAS-Cog tests in the studies carried out by Eagger et al. and Knapp et al. Moreover, Fitten et al. administered the highest tolerated THA dose to only a few patients enrolled in the study. The presence of broad CIs observed in the 5 meta-analytic studies infer non homogeneity of effects of treatment. Solely few patients improved, whereas the clinical conditions of the majority remained stationary. Between 5 and 10% of the outpatients in each single study presented reversible side effects calling for suspension of THA treatment. The optimal dose ranged between 80 and 160 mg THA, but often produced side effects. Comparative trials revealed the reduced efficacy and elevated toxicity of THA treatment, dampening the initial enthusiasm concerning the usefulness of this drug in AD. Furtermore, tacrine-induced side effects provoked many dropouts in all studies investigated. The effectiveness of tacrine treatment in AD disease was not fully confirmed. Other studies are required to identify doses and modalities of administration of this drug in AD.

Neurobehavioral syndrome induced by H2-receptor blocker withdrawal: possible role of prolactin

Cimetidine and ranitine are histamine H2-receptor blockers widely used for the treatment of gastric hypersecretion and duodenal pathologies. They are known to induce hyperprolactinemia in humans. Forty-six patients treated with cimetidine or ranitidine who were exhibiting a neurobehavioral syndrome after withdrawal of the drugs were selected. This syndrome was associated with a drop in plasma prolactin levels. The symptoms of this syndrome were greatly improved by restoration of treatment with the same drugs and reappeared when the treatment was again suspended. This syndrome was inhibited in 36 patients by administration of domperidone (30 mg/day), a drug inducing hyperprolactinemia without crossing the blood-brain barrier, as compared with 10 control patients treated with placebo. These results suggest that the drop in prolactin levels occurring when cimetidine and ranitidine are suspended may contribute to the development of this syndrome. Also, the withdrawal of H2-receptor blockers could be included among the possible causes of some neurotic syndromes.

Effects of acute or chronic administration of risperidone on motor and sexual behavior of male rats

A number of experiments were carried out to explore the behavioral profile of a novel antipsychotic, risperidone, after acute or chronic administration, in a dose range of 0.1-10 mg kg-1. This drug did not affect the acquisition and retention of avoidance behaviors in a dose of 0.1 mg kg-1, either after acute or chronic administration. Higher doses induced a inhibited acquisition and a facilitated extinction (only after chronic treatment) of active avoidance behavior, but no significant effect on the retention of passive avoidance responses. In contrast, haloperidol inhibited the acquisition and facilitated the extinction of active avoidance behavior, and reduced the retention of passive avoidance reaction at the dose of 0.1 mg kg-1 injected either acutely or chronically. Ambulation and rearing of rats rated in an open field was increased by risperidone injected acutely at the dose of 1 mg kg-1. Under the same experimental conditions, grooming appeared to be reduced. In the same test, acute or chronic haloperidol 1 or 10 mg kg-1 inhibited all behavioral items. Furthermore, in contrast to haloperidol, the acute or chronic administration of risperidone in a dose range of 0.1-10 mg kg-1 did not substantially induce catalepsy and did not affect apomorphine-induced stereotypies. Also, the dose of 0.1 mg kg-1 induced a facilitation of male sexual behavior by increasing the frequency and reducing the latency of mountings, intromissions and ejaculations, while haloperidol 1 or 10 mg kg-1 inhibited this behavior. These findings suggest that the pharmacological profile of risperidone differs from that of classical neuroleptics, like haloperidol, probably due to different mechanism or site of action.

Behavioral and neurochemical alterations induced by reversible conductive hearing loss in aged male rats

Eighteen months old male rats of the Sprague-Dawley strain were subjected to a reversible conductive hearing loss (HL) or a sham operation. A series of behavioral tests performed 3 months after surgery, revealed a sustained deficit in learning and memory capacity and a marked depressive attitude of rats with HL. At this time, a group of these animals were allowed to recover from HL for 1 month and were again tested behaviorally compared to those with persistent auditory deficit. A better performance at the active and passive avoidance tests and normal responsiveness to the despair test was found in animals with recovered hearing capacity as compared to those with persistent HL. A biochemical analysis revealed a decrease of dopamine and homovanillic acid content and of choline-acetyltransferase and acetylcholinesterase activity in the striatum and hippocampus of animals with persistent HL as compared to those with recovered auditory deficit. These data suggest that persistent auditory deafferentation affects cognitive mechanism in old rats in a reversible manner.

Vestibular compensation in aged rats with unilateral labyrinthectomy treated with dopaminergic drugs

Drugs acting as agonists (SKF38393 and quinpirol) or antagonists (SCH23390 and sulpiride) on dopamine receptors were administered at various doses (1, 2 or 4 mg kg-1 day-1) to aged male rats of the Sprague-Dawley strain subjected to labyrinth unilateral lesion. The time course of vestibular compensation was evaluated by recording spontaneous eye nystagmus and by scoring ambulation and rearing with the open field test and motor ability and coordination with the rotorod test. Treatment started 3 days prior to surgery and continued until day 7 after surgery. The vestibular compensation of untreated young male rats was also studied with the same methods. The decline of spontaneous nystagmus in aged animals was slower than that of young rats and was facilitated by the large doses of quinpirol (D2 receptor agonist) and inhibited by sulpiride (D2 receptor antagonist) 4 mg kg-1 day-1, while the other drugs did not affect this parameter. After operation, ambulation and rearing of aged rats increased more slowly as compared to that of young animals. Moreover, motor performance and coordination in aged rats improved less rapidly than those of young controls. Dopamine receptor agonists increased ambulation and improved motor performance and coordination in aged rats, while dopamine receptor antagonists exerted opposite effects. Rearing was not affected by any kind of drug treatment. These results suggest that dopamine neurotransmission plays a role in vestibular compensation process following unilateral labyrinthectomy in aged animals, and this may have clinical relevance in vestibular pathologies of peripheral origin that are associated to brain ageing.

Hysterical neurosis of the conversion type: therapeutic activity of neuroleptics with different hyperprolactinemic potency

To show a possible correlation between drug-induced hyperprolactinemia and improvement of hysterical neurosis of the conversion type, we followed 18 patients monitoring clinical somatic and psychic symptoms as well as serum prolactin levels. Six patients were treated with haloperidol and 12 with sulpiride; after 2 months sulpiride was administered at half the daily dose to 6 patients previously treated with the same drug. Clinical evaluation showed that sulpiride treatment led to a greater improvement compared to the haloperidol group. The different effectiveness of treatment could be explained by the different hyperprolactinemic potency. The therapeutic efficacy of neuroleptics suggests also that hyperactivity of dopaminergic transmission is involved in the pathophysiology of hysterical neurotic symptoms.

Transient global amnesia and cerebral infarct: a case report

Transient global amnesia refers to a sudden and isolated dysfunction of memory for recent events, lasting a few hours. The pathogenesis of this neurological disorder is still uncertain. The most accepted hypotheses concern ischaemic, epileptic and migraine causes. We now report a case of transient global amnesia associated with computed tomography evidence for a hypodense area in the left thalamus 10 days after the transient memory dysfunctions.

Comparative effects of amitriptyline and amineptine in patients affected by anxious depression

In a double-blind, placebo-controlled study, the therapeutic efficacy of two antidepressants with different neurochemical mechanisms of action, amitriptyline and amineptine, was investigated in patients affected by anxious depression. Sixty-six patients with the primary diagnosis of major depression or bipolar affective disorder (DSM-III-R) and meeting additional operational clinical criteria such as anxiety, trepidation, restlessness, early and/or late insomnia, impulsivity, hostility, dysphoria, compulsivity, hyperperspiration, palpitation, pollakiuria and phobias were included. They were randomly assigned to three groups (n = 22) and treated either with placebo, amitriptyline (up to 100 mg/day) or amineptine (up to 200 mg/day) for 6 weeks. Patients showed better response to amitriptyline, a preferential inhibitor of serotonin reuptake, than to amineptine, a selective inhibitor of dopamine reuptake. The present results suggest that alterations in serotonergic rather than dopaminergic transmission contribute to the pathophysiology of anxious depression.

Effects of TRH-T on spinal motoneurones in man

The effect of thyrotropin-releasing hormone tartrate (TRH-T) on the decrease in H Max/M Max ratio, an index of the spinal motoneurone pool, induced by haloperidol, was studied in 15 healthy volunteers. In all subjects, the H response was examined by an electromyographic apparatus. The values were expressed as H Max/M Max ratio, that gives an index of excitability of the spinal motoneurone pool. It was found that the mean H Max/M Max ratio value significantly decreased after haloperidol administration, but this effect was completely reversed by the injection of TRH-T. This finding suggests that the peptide may modulate motoneurone functions.

Homologous and heterologous adenylate cyclase system desensitization in glial cells

In the present research the desensitization of adenylate cyclase system induced by isoproterenol (IPR), a beta-adrenergic agonist, in primary glial cell cultures and the effects of an exposure to 3-isobutyl-1-methylxanthine (IBMX) on the response to a subsequent stimulation with IPR have been investigated. A pretreatment with the phosphodiesterase inhibitor IBMX induced refractoriness to a subsequent IPR challenge suggesting a possible involvement of cAMP in heterologous desensitization. Moreover the present results show that IPR desensitized cells in confluent cultures retained a normal response to cholera toxin, while IBMX treated cells exhibited a reduced response to the toxin. So IPR induces a rather specific desensitization while IBMX induced refractoriness seems to be non specific.

Behavioral effects of L-alpha-glycerylphosphorylcholine: influence on cognitive mechanisms in the rat

The phosphorylcholine precursor, L-alpha-glycerylphosphorylcholine (alpha-GPC), was injected at the dose of 100 mg/kg/day for 20 days to aged male rats of the Sprague-Dawley strain, 24 months old, showing a deficit of learning and memory capacity. The drug was also administered to rats with amnesia induced pharmacologically with bilateral injections of kainic acid into the nucleus basalis magnocellularis (NBM). Learning and memory capacity of the animals, studied with tests of active and passive avoidance behavior, was improved after treatment with alpha-GPC in all experimental groups. These results indicate that this drug affects cognitive mechanisms in the rat through an involvement of central neurotransmission.

Trophic action of acetyl-L-carnitine in neuronal cultures

Daily addition of acetyl-L-carnitine (100 microM) to cultured cerebellar granule cells since the first day of maturation led to an increased rate of expression of D-[3H]aspartate uptake (an established marker of maturation of glutamatergic neurons) and of N-methyl-D-aspartate (NMDA) receptors linked to large conductance ion channels permeable to Ca2+. Acetyl-L-carnitine treatment also increased neuronal survival, as reflected by a greater percentage of cultures retaining functional NMDA receptors after 15 days of maturation. These results support the view that acetyl-L-carnitine exerts neuronotrophic activity and prevents age-dependent neuronal degeneration.

Dopaminergic hypothesis for retarded depression: a symptom profile for predicting therapeutical responses

We assessed the therapeutical efficacy of various antidepressants (amineptine, minaprine and clomipramine) in patients affected by retarded depression. All patients exhibited symptoms of retardation, including hypokinesia, anergia, reduction of speech, increased salivation, hypersomnia, Parinaud's syndrome, reduced sexual activity, slowness, hypomimia, orthostatic hypotension, dysphagia and drowsiness. Antidepressant drugs were administered for a 6-week period in a randomized double-blind vs placebo design. The rank order of clinical effectiveness (amineptine much greater than minaprine greater than clomipramine greater than placebo) paralleled the specificity of antidepressants as dopaminomimetic agents. These results support the view that a reduced dopaminergic transmission contributes to the pathophysiology of retarded depression.

Adenosine deaminase increases release of excitatory amino acids through a mechanism independent of adenosine depletion

Addition of adenosine deaminase to cultured cerebellar neurones, led to large increases in the influx of 45Ca2+ and hydrolysis of polyphosphoinositide. These effects were inhibited or attenuated by glutamate receptor antagonists (AP5 or MK-801) and were not observed in cells stimulated by maximum concentrations of glutamate or quisqualate. Stimulation of the influx of 45Ca2+ and hydrolysis of phosphoinositide by adenosine deaminase may be secondary to an enhanced release of endogenous glutamate that in turn activates specific excitatory amino acid receptors. Accordingly, adenosine deaminase potently increased release of D-[3H]aspartate, an effect that requires the presence of extracellular Na+ and is insensitive to inhibition by MK-801. None of the effects of adenosine deaminase may be simply related to a fall in endogenous adenosine. In fact, the action of adenosine deaminase was neither reversed by agonists (L-PIA or NECA), nor mimicked by antagonists (IBMX or theophylline) of adenosine receptors. It is speculated that adenosine deaminase stimulates release of neurotransmitter through a mechanism independent of depletion of adenosine. A possible direct action of adenosine deaminase should be taken into account when the enzyme is used to unmask the effects of endogenous adenosine.

[The H2-antagonist therapy withdrawal syndrome: the possible role of hyperprolactinemia]

Patients previously treated with H2-receptor blocking agents (cimetidine or ranitidine) exhibited a complex neurobehavioral and gastroenteric syndrome, including anxiety, insomnia, anorexia, growing thin, irritability, tachycardia, diarrhoea, nausea, vomiting, abdominal pain, headache, vertigo. These symptoms were dramatically reduced by administration of cimetidine or ranitidine, and reappeared with a new suspension of the therapy. The withdrawal syndrome from H2-receptor antagonists was reversed by treatment with domperidone (10 mg three times per day), a potent hyperprolactinaemic drug which does not cross the blood brain barrier. These results suggest that the drop in prolactin levels that occurs when cimetidine or ranitidine are suspended may contribute to the development of the withdrawal syndrome.

[Tardive dyskinesia. A possible complication of chronic treatment with neuroleptics]

Tardive dyskinesia consists of abnormal involuntary movements at the oro-facial area (mouth, tongue, maxillary) or generalized choreoathetotic disorders of the limbs and trunk occurring in at least 10-20% of chronically neuropsychiatric patients exposed to neuroleptics. Age (over 50), gender (female), affective disorders, individual predisposition, type of drug, dosage and duration of neuroleptic exposure (over 3 months), anticholinergics, appear to be risk factors. In this brief review some current pathophysiological mechanisms and clinical therapeutical trials are also discussed.

L-acetylcarnitine attenuates the age-dependent decrease of NMDA-sensitive glutamate receptors in rat hippocampus

NMDA-sensitive glutamate receptors are involved in the regulation of neuronal plasticity, and contribute to the synaptic mechanisms underlying the learning process. Aging is associated with a reduction in the maximal density of NMDA-sensitive glutamate binding sites in rat hippocampus. This reduction is attenuated after long-term administration with L-acetylcarnitine (10 mg/Kg i.p. once a day for 4 months). These results support a neuroprotective and neurotrophic role for L-acetylcarnitine during aging.

[Effects of zinc sulfate on limbic motor epilepsy induced by kainic acid]

In the present study the Authors have investigated the effects of chronic pretreatment with injections of Zn++ sulphate solution on kainic acid induced epilepsy, to verify wether or not Zn++ is able to change the epileptiform pattern induced by kainic acid infection. Results obtained show that Zn++ do not produce any significant change in the experimental parameters by us study.

Influence of sex steroids and prolactin on haloperidol-induced catalepsy

The effects of sex steroids and prolactin on haloperidol-induced catalepsy were investigated in male rats. Repeated administration with estradiol benzoate (5 micrograms/rat, twice daily for 10 days) significantly potentiated catalepsy induced by 0.25 or 0.5 mg/kg haloperidol, but no effect was observed 10 min or 1 h after a single injection of estradiol benzoate (5 or 50 micrograms/rat). Conversely, a single administration with the catecholestrogen 2-hydroxyestradiol (50 micrograms/rat) significantly increased haloperidol-induced catalepsy, suggesting that catecholestrogens may directly interfere with nigrostriatal dopaminergic transmission. Haloperidol-induced catalepsy has been found to be attenuated in conditions of hyperprolactinaemia resulting from anterior pituitary isograft underneath the kidney capsule. This is consistent with the hypothesis that prolactin may stimulate nigro-striatal dopaminergic function. Results obtained also indicate that medroxy-acetate progesterone, a progesterone derivative, may influence haloperidol-induced catalepsy. Specifically, a single administration with medroxy-acetate progesterone (5 mg/kg, i.p.) enhanced catalepsy but opposite effects were observed after repeated administration of medroxy-acetate progesterone (5 mg/kg, i.p., once a day for 7 days).

Effects of dopaminergic drugs on cerebellar prostaglandin concentrations

Previous data indicate that the injection of dopaminergic drugs induces changes in cerebellar 3',5'-guanosine monophosphate (cGMP) content. Accordingly, we have investigated the effects of haloperidol, sulpiride, or apomorphine on cerebellar prostaglandin (PG) concentration, a parameter related to cGMP content. Results obtained show that dopamine receptor blocking agents, such as haloperidol and sulpiride, significantly decrease cerebellar PGE2 and PGF2 alpha concentrations, while opposite changes are induced by apomorphine, a dopamine receptor agonist.