Fluphenazine Treatment Research Articles

Melatonin-mediated attenuation of fluphenazine-induced hypokinesia in C57BL/6 mice is dependent on the light/dark phase

Our aims were to assess the effect of melatonin on fluphenazine-induced hypokinesia during the light (ZT 9.5–10.5) and dark (ZT 17.5–18.5) phases in mice lacking endogenous pineal melatonin (C57BL/6 mouse), and to investigate the effects of the manipulation of environmental lighting in mice with a targeted deletion of the MT1 melatonin receptor. In both knockout (C57KO MT1) and wild type (C57WT) mice, fluphenazine (1 mg/kg) induced hypokinesia during the light phase (C57WT: M=105, SEM=31.2 s, n = 31; C57 MT1KO:M=118, SEM = 32.6 s, n = 29). During the light phase melatonin (10 mg/kg, sc) significantly reduced hypokinesia in both genotypes (C57WT: M=33.1, SEM=8.4 s; C57 MT1KO: M=33.3, SEM=13.0 s). In the dark, fluphenazine did not induce a substantial hypokinesia in either C57WT or C57 MT1KO mice. Manipulating the lightning environment during testing, experiments conducted during the light phase in a dark environment served to abolish the hypokinetic effect of fluphenazine in all groups regardless of melatonin treatment. Conversely, experiments conducted during the dark phase in a light environment showed mice to have hypokinetic effects by fluphenazine treatment in both C57WT (M=98.4, SEM=20.2 s) and C57 MT1KO (M=40.4 SEM=9.5 s) groups. These data suggest that fluphenazine-induced hypokinesia is more pronounced under light than dark conditions, and that melatonin is only able to counteract hypokinesia during the light phase. Importantly, our data suggest that the effect of melatonin on hypokinesia was not solely mediated by the MT1 melatonin receptor in the C57BL/6 mouse, leaving the possible activation of MT2 receptor as the mechanism of action which is regulated by the light/dark environment.

Resveratrol Protects Against Vacuous Chewing Movements Induced by Chronic Treatment with Fluphenazine.

Typical antipsychotics, which are commonly used to treat schizophrenia, cause motor disorders such as tardive dyskinesia (TD)in humans and orofacial dyskinesia (OD) in rodents. The disease mechanisms as well as treatment effectiveness are still unknown. In this study, we investigated the effect of resveratrol, a polyphenol with neuroprotective properties, on behavioral changes induced by chronic treatment with fluphenazine in rats and the possible relationship between monoamine oxidase (MAO) activity and vacuous chewing movements (VCMs). Rats were treated for 18weeks with fluphenazine enantate [25mg/kg, intramuscularly (i.m.), every 21 days] and/or resveratrol (20mg/kg, offered daily in drinking water). Next, body weight gain, behavioral parameters (VCMs and open field tests-locomotor and rearing activity), and MAO activity were evaluated. Fluphenazine treatment reduced body weight gain, number of crossings and rearings, and the co-treatment with resveratrol did not affect these alterations. Fluphenazine increased the prevalence and intensity of VCMs and the co-treatment with resveratrol reduced the VCMs. Furthermore, a negative correlation was found between the number of VCMs and MAO-B activity in the striatum of rats. Our data suggest that resveratrol could be promissory to decrease OD. Moreover, MAO-B activity in the striatum seems to be related to VCMs intensity.

Effect of typical and atypical antipsychotic drugs on serum C-reactive protein and lipid profile in schizophrenic patients

Objectives: To assess the effect of quetiapine and fluphenazine on serum high sensitivity C-reactive protein (hs-CRP) and serum lipid profile in schizophrenic patients. Patients and methods: The subjects comprised two groups of twenty seven newly diagnosed schizophrenic patients for each group. The first group was treated orally with quetiapine at a dose 200-500 mg/day. The second group was treated with fluphenazine intramuscularly at a dose 25 mg every 4 weeks. Twenty seven healthy volunteers were also included as a control group. The patient and the control groups were age and sex matched. The patients were diagnosed by a psychiatrist on the basis of semi-structured interview to determine DMS-IV diagnosis. Clinical symptoms were assessed in 14 of the 18 Brief individual Psychiatry Rating Scale (BPRS) items in order to measure the severity of schizophrenia. Fasting blood samples from the patients were taken for analysis before the beginning of quetiapine or fluphenazine treatment and after 8 weeks of the study. Other blood samples were taken from healthy subjects as a control group. Results: Serum hs-CRP was significantly (p  0.01) higher in the schizophrenic patients before treated by quetiapine or fluphenazine (difference = 382.9% and 395.1% of control, respectively) than controls. The measurement of hs-CRP decreased significantly (p  0.01) after quetiapine treatment by 19.1%, while it was increased significantly (p  0.01) after fluphenazine by 12.3% compared with before treatment values. In the schizophrenic patients, serum total cholesterol (TC) and triglycerides (TG) were significantly higher (p  0.01) than controls, while high density lipoprotein cholesterol (HDL-C) was lower than controls. Quetiapine caused significant increase (p  0.01) in serum TC and TG, while serum HDL-C decreased significantly (p  0.01) compared with the results before treatment. Fluphenazine did not cause any significant change in the lipid parameters. Quetiapine treatment significantly increased (p  0.05) body mass index (BMI), whereas fluphenazine did not change BMI compared with before treatment values. Base time and after 8 weeks of quetiapine or fluphenazine treatment showed significant decrease in the score of BPRS by quetiapine and fluphenazine. Conclusion: Quetiapine depressed CRP and caused dyslipidemia. Fluphenazine raised CRP but it had no effect on lipid profile.

Resveratrol reduces vacuous chewing movements induced by acute treatment with fluphenazine

Treatment with classical neuroleptics in humans can produce a serious side effect, known as tardive dyskinesia (TD). Here, we examined the possible neuroprotective effects of resveratrol, a polyphenol compound contained in red grapes and red wine, in an animal model of orofacial dyskinesia (OD) induced by acute treatment with fluphenazine. Adult male rats were treated during 3weeks with fluphenazine enantate (25mg/kg, i.m., single administration) and/or resveratrol (1mg/kg, s.c., 3 times a week). Vacuous chewing movements (VCMs), locomotor and exploratory performance were evaluated. Fluphenazine treatment produced VCM in 70% of rats and the concomitant treatment with resveratrol decreased the prevalence to 30%, but did not modify the intensity of VCMs. Furthermore, the fluphenazine administration reduced the locomotor and exploratory activity of animals in the open field test. Resveratrol co-treatment was able to protect the reduction of both parameters. Taken together, our data suggest that resveratrol could be considered a potential neuroprotective agent by reducing motor disorders induced by fluphenazine treatment.

Chronic Treatment with Fluphenazine Alters Parameters of Oxidative Stress in Liver and Kidney of Rats

The aim of this study was to assess the toxic effects of chronic exposure to fluphenazine in liver and kidney of rats, as well as the possible protective effect of diphenyl diselenide on the fluphenazine-induced damage. Long-term treatment with fluphenazine caused an increase in lipid peroxidation levels in liver and kidney homogenates. Diphenyl diselenide treatment did not affect delta-aminolevulinate dehydratase (delta-ALA-D) activity, but fluphenazine alone or in combination with diphenyl diselenide showed an inhibitory effect on delta-ALA-D activity in liver. Diphenyl diselenide plus fluphenazine treatment increased the reactivation index of hepatic delta-ALA-D by approximately 80%. Superoxide dismutase activity decreased in liver of rats treated with fluphenazine alone. The combined treatment with fluphenazine and diphenyl diselenide was able to ameliorate superoxide dismutase activity in liver of rats. Catalase activity was augmented in liver from rats treated with fluphenazine, and this increase was prevented when diphenyl diselenide was co-administered. Taken together, these results indicate that the association of diphenyl diselenide with fluphenazine could protect the liver from lipid peroxidation and ameliorate superoxide dismutase and catalase activities. Moreover, our data point to the relationship between the oxidative stress and fluphenazine treatment in liver and kidney of rats.

Diphenyl diselenide decreases the prevalence of vacuous chewing movements induced by fluphenazine in rats

Chronic treatment with neuroleptics causes, as a side effect, tardive dyskinesia in humans; however, the mechanisms involved in its pathophysiology remain unclear. The purpose of this study was to examine the effects of diphenyl diselenide, an organoselenium compound with antioxidant properties, in an animal model of vacuous chewing movements (VCMs) induced by long-term treatment with fluphenazine. Adult male rats were treated during 24 weeks with fluphenazine (25 mg/kg, intramuscularly [i.m.], once every 21 days) and diphenyl diselenide (1 mg/kg, subcutaneously, three times a week). VCMs and body weight gain were quantified every 3 weeks. The fluphenazine treatment produced VCMs in the majority of the treated rats (87% after 24 weeks). Concomitant treatment with diphenyl diselenide decreased the prevalence of VCMs to 50%. Additionally, we separated the rats that developed or did not develop VCMs. We did not find any statistical differences among the groups when oxidative stress parameters were evaluated. Chronic fluphenazine treatment significantly decreased [(3)H]-dopamine uptake. Concomitant treatment with diphenyl diselenide was not able to prevent this decrease in those rats that developed VCMs. Our data suggest that the reduction in dopamine transport can be a possible mechanism related to the maintenance of VCMs in rats. Moreover, diphenyl diselenide seems to be a promising pharmacological agent in the reduction in the prevalence of VCMs in rats.

The effects of olanzapine and fluphenazine on plasma cortisol, prolactin and muscle rigidity in schizophrenic patients: A double blind study

Pharmacotherapy of schizophrenia is associated with the stressful side effects. Muscle rigidity causes distress, discomfort and poor compliance. The aim of the study was to determine the relationship between plasma hormones (cortisol and prolactin/PRL) and muscle rigidity in female schizophrenic patients treated with olanzapine or fluphenazine. In a randomized, double-blind 22-weeks study, 12 patients were treated with olanzapine (5–20 mg/day) and 10 patients received fluphenazine (6–21 mg/day). Treatment with olanzapine moderately decreased, while treatment with fluphenazine significantly increased plasma cortisol levels and muscle rigidity. The marked and moderate increase in plasma PRL levels were found in patients treated with fluphenazine and olanzapine, respectively. The results suggested that olanzapine induced moderate neuroendocrine effects and a reduction in rigidity as compared to fluphenazine treatment.

Hyperprolactinemia affects spermiogenesis in adult male rats

The mechanisms underlying the antifertility effects of hyperprolactinemia have yet to be established in an appropriate experimental model. Hyperprolactinemia is a known side effect of fluphenazine, a broad spectrum, long-acting phenothiazine known to be dopamine type-D2 receptor antagonist. In our earlier study in adult male rats, we reported that fluphenazine at a dose of 3 mg/kg/day suppressed serum FSH but not testosterone (T) through increasing dopamine (DA) metabolism in the pituitary gland, within 60 days. Fluphenazine treatment affected sperm quality and male rats treated with fluphenazine sired fewer litters. The effects of fluphenazine-induced hyperprolactinemia on sperm quality appeared to be related to reduced FSH. We now report that FSH suppression enhanced the uptake of acridine orange (AO), a DNA intercalating, fluorescent dye by the fluphenazine-treated caput epididymal sperms with concomitant reduction in the uptake of thiol-specific monobromobimane (mBBr) fluorescent dye in vitro, suggesting greater accessibility of DNA intercalating dye to sperm chromatin and reduction in free sperm protein thiols. The concomitant increase in AO and decrease in mBBr fluorescence was suggestive of loose chromatin packaging in caput epididymal sperms after treatment with fluphenazine at 3 mg/kg/day for 60 days. The suppression in levels of protamine (P1) in caput epididymal sperms suggested that chromatin hypocompaction was due to reduced deposition of protamines in sperm chromatin. Reduction in testicular levels of cyclic adenosyl 3', 5' monophosphate response element modulator (CREMtau) and P1 further suggested that reduced deposition was indeed due to reduced synthesis. The concomitant reduction in testicular levels of transition protein 1 (TP1) and transition protein 2 (TP2) also suggested that hypoprotamination was due to reduced synthesis of these proteins crucial for facilitating P1 deposition. The effect appeared to have occurred at the level of translation of CREMtau, since its transcript levels were unaffected whereas those of TP1, TP2 and P1 and protamine were upregulated. The study led to the view that the effects of FSH suppression were manifest on the posttranscriptional modifications of CREMtau, as also on transcript repression of TP1, TP2, P1, which do the RNA- binding proteins bring about. Reduction in FSH did not decrease ABP expression in the testis, which has recently been implicated in the expression of transition protein 1 in vitro. However, a significant reduction was evident after fluphenazine treatment, in the immunoexpression of testicular cAMP, the mediator of FSH effects in the Sertoli cells and putative mediator of ABP effects in the spermatids. The study suggests that fluphenazine-induced hyperprolactinemia suppressed FSH and affected a putative cAMP-dependent mechanism underlying posttranscriptional modification of spermatidal genes involved in chromatin condensation, presumably by reducing the availability/secretion of ABP, a paracrine regulator of spermiogenesis in vitro.

Carbamazepine for acute psychosis with eeg abnormalities

To investigate the efficacy of carbamazepine as adjuvant drug therapy in acute paranoid psychosis with associated EEG abnormalities, compared to sole antipsychotic treatment. Eleven medication-naive patients, diagnosed with acute paranoid psychosis with associated EEG abnormalities, were divided into two treatment groups: sole fluphenazine group, with flexible dosing of 5-10 mg/day (n=6), and carbamazepine group (n=5) with the addition of carbamazepine (600 mg/day) to fluphenazine treatment. Clinical Global Impression (CGI), Brief Psychiatric Rating Scale (BPRS), Scale for the Assessment of Negative Symptoms (SANS), and EEG were assessed on the baseline and after 6 weeks of treatment. Paired and two-tailed t-tests were used for statistical significance. All the patients showed significant improvement of mental state after 6 weeks of treatment with no significant differences in CGI, BPRS, and total SANS scores in relation to the therapy with carbamazepine. Nevertheless, after 6 weeks of the treatment, EEG findings were significantly better in carbamazepine group, in relation to the findings from the onset of the treatment, as well as in comparison to sole fluphenazine group. Although carbamazepine stabilized abnormal brain electrical activities it seemed that the associated EEG abnormalities were not significant for acute psychosis observed. These preliminary results suggested that there was no convincing evidence that carbamazepine was efficient as the augmentation of antipsychotic treatment for patients with both acute paranoid psychosis and EEG abnormalities.

Blockade of nigral and pallidal opioid receptors suppresses vacuous chewing movements in a rodent model of tardive dyskinesia

Chronic neuroleptic treatment leads to the development of tardive dyskinesia in 20–30% of patients. While the pathogenesis of tardive dyskinesia remains elusive, altered opioid peptide function in striatal projection pathways of the basal ganglia has been implicated. Using a rodent model of vacuous chewing movements induced by chronic neuroleptic administration, we investigated regional involvement of opioid transmission in tardive dyskinesia. We examined the role of dynorphin in the direct striatonigral pathway by infusing nor-binaltorphimine, a selective κ opioid receptor antagonist, into the substantia nigra pars reticulata. As well, infusions of naloxone (a non-specific opioid receptor antagonist), D-Phe-Cys-Tyr- D-Trp-Orn-Thr-Pen-Thr amide (CTOP; a μ opioid receptor antagonist) or naltrindole (a δ opioid receptor antagonist) into the globus pallidus were used to establish the contribution of the striatopallidal pathway. Chronic fluphenazine treatment (25 mg/kg i.m. every 3 weeks for 18 weeks) resulted in a robust increase in vacuous chewing movements. Infusion of nor-binaltorphimine (5.0 nmol) into the substantia nigra pars reticulata significantly attenuated vacuous chewing movements. Infusion of naloxone (0.5 and 2.0 nmol) into the globus pallidus also significantly attenuated vacuous chewing. Infusion of naltrindole into the globus pallidus blocked vacuous chewing at all doses administered (0.5, 1.0, 2.0 nmol) while CTOP was only effective at the two higher doses. From these results we suggest that increases in dynorphin in the direct striatonigral pathway and enkephalin in the indirect striatopallidal pathway following chronic neuroleptic administration are both likely to contribute to tardive dyskinesia.

Systemic relaxin in pregnant pony mares grazed on endophyte-infected fescue: effects of fluphenazine treatment

Tall fescue is one of the most widely grown forage grasses for horses in the United States. However, it is frequently infected with the endophyte Neotyphodium coenophialum which produces ergot alkaloids that cause severe adverse effects in the pregnant mare. The objectives of this study were to determine the effects of fescue toxicosis and fluphenazine on circulating relaxin in pregnant pony mares and evaluate the usefulness of relaxin as a monitor of treatment efficacy. Twelve mares were maintained on endophyte-infected tall fescue pasture. Group TRT (n = 6), received 25 mg of fluphenazine decanoate (im) on Day 320 of gestation while Group UTRT served as untreated controls. Daily blood samples were collected from Day 300 of gestation until Day 3 post partum and analyzed for plasma relaxin concentrations using a homologous equine radioimmunoassay. Mean gestation lengths were 330 ± 0.7 and 336.5 ± 3.2 days for TRT and UTRT mares, respectively (P = 0.07). Mean plasma relaxin concentrations in both groups of mares during the week before treatment (Day 313 to 319) were not different (UTRT, 53.4 ± 11.3 ng/mL; TRT, 61.4 ± 9.3 ng/mL). In the week after treatment (Day 320 to 326), mean plasma relaxin tended to be higher (P = 0.1) in TRT mares (66.7 ± 6.2 ng/mL) when compared with UTRT mares (49.6 ± 6.6 ng/mL), representing a 17.1 ng/mL difference in circulating relaxin between the two groups. Systemic relaxin during the last week before delivery (days relative to parturition) for UTRT and TRT mares was 45.7 ± 6.7 and 64.7 ± 6.4 ng/mL (P = 0.06), respectively. At Day −8 and Day −5 relative to parturition, systemic relaxin in TRT mares was significantly higher (P < 0.05) than in UTRT mares. Three of the six UTRT mares and one TRT mare showed clinical symptoms of fescue toxicosis. In the week before delivery, circulating relaxin in mares with problematic pregnancies (39.9 ± 7.8 ng/mL) was significantly lower than concentrations measured in mares with normal pregnancies (63.4 ± 5.4 ng/mL; P = 0.03). Clinical observations suggest that a one-time injection with fluphenazine improved pregnancy outcome by reducing the adverse effects of fescue toxicosis concomitant with a stabilization of plasma relaxin concentrations. These data support the hypothesis that systemic relaxin may be a useful biochemical means of monitoring placental function and treatment efficacy in the mare.

A preliminary study of the comparative effects of olanzapine and fluphenazine on cognition in schizophrenic patients.

The aim of the study was to compare the effect of olanzapine versus fluphenazine treatment on cognitive functioning. Eighteen schizophrenic outpatients, aged 25 - 61 (average 37 years), all meeting DSM-IV diagnostic criteria for schizophrenia, were included in the study. They were randomly assigned to 22 weeks of either olanzapine or fluphenazine treatment. Certain subscales of the Wechsler Adult Intelligence Scale, the Stroop Neuropsychological Screening Test and the Wisconsin Card Sorting Test were performed. Olanzapine treatment proved to have a beneficial effect on digit-symbol performance and some aspects of executive function. In comparison to the fluphenazine treatment, the olanzapine treatment only showed a beneficial effect in increased percentage of conceptual level responses. Although the results are preliminary, they could implicate that the benefit of olanzapine treatment is primarily related to certain aspects of executive function, i.e. frontal lobe functioning. Copyright 2000 John Wiley & Sons, Ltd.

Is schizophrenia an autoimmune disease?

Changes in D2-like dopamine (DA) receptor binding in rat brain regions were compared by quantitative in vitro receptor autoradiography after 21-d treatment with a typical (fluphenazine), atypical (clozapine), or candidate atypical antipsychotic (S[+]-N-n-propylnorapomorphine, [+]-NPA). Fluphenazine treatment significantly increased binding of the D2,3,4 radioligands [3H]nemonapride and [3H]spiperone in caudate-putamen (CPu: 22%, 32%), nucleus accumbens (ACC: 67%, 52%), olfactory tubercle (OT: 53%, 43%), and medial prefrontal cerebral cortex (MPC: 46%, 47%) but not dorsolateral frontal cortex (DFC). D2-like binding in MPC was also increased by (+)-NPA (49%, 39%) and clozapine (60%, 40%), but not in DFC, CPu, ACC, or OT. Binding of D2,3-selective [3H]raclopride increased less after fluphenazine in ACC (27%) and CPu (16%) than with the nonselective radioligands, and not after clozapine or (+)-NPA. D3-selective binding of [3H]R(+)-7-OH-DPAT was not changed with any treatment or region including islands of Calleja. Binding of [3H]nemonapride or [3H]spiperone under D4-selective conditions (with 300 nM S[−]-raclopride and other masking agents, at sites occluded by D4 ligand L-745,870), was increased by fluphenazine, (+)-NPA, clozapine in ACC (120%, 76%, 70%, respectively), and CPu (54%, 37%, 35%), but not in OT, DFC or MPC. These results support the hypothesis that cerebrocortical D2-like and striatolimbic D4-like receptors contribute to antipsychotic actions of both typical and atypical drugs and encourage further consideration of S(+)aporphines as potential atypical antipsychotics.

Long-Term Effects of S(+)N-n-Propylnorapomorphine Compared with Typical and Atypical Antipsychotics: Differential Increases of Cerebrocortical D2-Like and Striatolimbic D4-Like Dopamine Receptors

Changes in D2-like dopamine (DA) receptor binding in rat brain regions were compared by quantitative in vitro receptor autoradiography after 21-d treatment with a typical (fluphenazine), atypical (clozapine), or candidate atypical antipsychotic (S[+]-N-n-propylnorapomorphine, [+]-NPA). Fluphenazine treatment significantly increased binding of the D2,3,4 radioligands [3H]nemonapride and [3H]spiperone in caudate-putamen (CPu: 22%, 32%), nucleus accumbens (ACC: 67%, 52%), olfactory tubercle (OT: 53%, 43%), and medial prefrontal cerebral cortex (MPC: 46%, 47%) but not dorsolateral frontal cortex (DFC). D2-like binding in MPC was also increased by (+)-NPA (49%, 39%) and clozapine (60%, 40%), but not in DFC, CPu, ACC, or OT. Binding of D2,3-selective [3H]raclopride increased less after fluphenazine in ACC (27%) and CPu (16%) than with the nonselective radioligands, and not after clozapine or (+)-NPA. D3-selective binding of [3H]R(+)-7-OH-DPAT was not changed with any treatment or region including islands of Calleja. Binding of [3H]nemonapride or [3H]spiperone under D4-selective conditions (with 300 nM S[−]-raclopride and other masking agents, at sites occluded by D4 ligand L-745,870), was increased by fluphenazine, (+)-NPA, clozapine in ACC (120%, 76%, 70%, respectively), and CPu (54%, 37%, 35%), but not in OT, DFC or MPC. These results support the hypothesis that cerebrocortical D2-like and striatolimbic D4-like receptors contribute to antipsychotic actions of both typical and atypical drugs and encourage further consideration of S(+)aporphines as potential atypical antipsychotics.

Idazoxan and Response to Typical Neuroleptics in Treatment-Resistant Schizophrenia

We investigated whether antagonism of alpha 2 adrenergic receptors would augment treatment response in schizophrenia, by administering idazoxan, an alpha 2 antagonist drug, to treatment-resistant patients on typical neuroleptics. Seventeen hospitalised treatment-resistant patients with DSM-III-R schizophrenia or schizoaffective disorder were studied on typical neuroleptic treatment, on treatment with idazoxan plus typical neuroleptic, and after discontinuation of idazoxan, in fixed, non-random order, and under double-blind, placebo-controlled conditions. The addition of idazoxan to fluphenazine treatment resulted in significant reductions of global psychosis and total, positive and negative symptoms on the Brief Psychiatric Rating Scale, compared to neuroleptic treatment alone. Symptom improvement significantly correlated with idazoxan-induced changes in indices of noradrenergic function. In a subgroup of patients, idazoxan plus typical neuroleptic treatment compared favourably with clozapine treatment, when both were compared to typical neuroleptic treatment alone. The antagonism of alpha 2 receptors augmented therapeutic response to typical neuroleptic treatment in treatment-resistant patients with schizophrenia. This antagonism may contribute to clozapine's superior antipsychotic effects.

Neuroleptics differentially modulate central dopamine D1-receptor binding.

The effect of the classical neuroleptic, fluphenazine, on dopamine D1-receptor binding was examined in different regions of the basal ganglia. Whereas exposure to fluphenazine for 18 months reduced [125I]SCH-23982 binding to D1-receptors in the caudate putamen, nucleus accumbens and olfactory tubercle, binding in the entopeduncular nucleus was enhanced after fluphenazine treatment. Competition studies indicated that the region-dependent changes in [125I]SCH-23982 binding after fluphenazine exposure were not due to differences in the affinity of fluphenazine or other dopamine ligands for D1-binding sites. These data suggest that in addition to modulating striatal function, classical neuroleptics may also alter neurotransmission in the basal ganglia by enhancing dopamine receptor binding in the entopeduncular nucleus.

Chronic treatment with a classical neuroleptic alters excitatory amino acid and GABAergic neurotransmission in specific regions of the rat brain

The purpose of the following experiments was to describe some of the neurochemical changes that occur in the basal ganglia of rats exposed chronically to a classical neuroleptic, fluphenazine, and to relate these changes to extrapyramidal motor dysfunction. For these studies a combination of behavioural, receptor autoradiographic and in situ hybridization methods were employed. Preliminary pharmacological studies on GABA receptors showed that incubation in Tris-acetate rather than Tris-citrate buffer increased the number of binding sites labelled by [ 3H]muscimol by over 120% without affecting binding affinity or selectivity. The results of experiments with fluphenazine showed that treatment for six months increased the frequency of vacuous chewing movements compared to controls. In the striatum, changes in GABA transmission were observed in fluphenazine-treated rats with increases in glutamate decar☐ylase mRNA levels in the caudate nucleus, dorsal shell and core of the accumbens and decreases in [ 3H]muscimol binding in the caudate and dorsal shell regions. These data suggest that fluphenazine treatment increased GABA transmission in specific subregions of the candate and accumbens nuclei. In addition, glutamate decar☐ylase mRNA levels were elevated in the entopeduncular nucleus of fluphenazine-treated animals. Autoradiographic analysis of excitatory amino acid binding showed that fluphenazine exposure decreased [ 3H]α-amino-3-hydroxy-5-methylisoxazole-4-propionic acid binding in entopeduncular nucleus and in the ventrolateral thalamic nucleus and decreased [ 3H]dizocilpine maleate binding in the medial geniculate nucleus. These experiments show that in addition to altering GABA transmission, chronic neuroleptic exposure alters excitatory amino acid transmission in specific regions of the basal ganglia-thalamocortical motor system. The neuroleptic dependent increases in glutamate decar☐ylase mRNA levels in the entopeduncular nucleus may reflect changes in neurotransmission in the indirect pathway connecting the major input and output nuclei of the basal ganglia. Changes in some of these brain regions may be related to the occurrence of extrapyramidal motor disturbances.

BIRTH ORDER, FAMILY SIZE, AND SCHIZOPHRENIC SYMPTOMS

We examined the statistical relationships of position in the birth order and number of siblings to symptoms relevant for diagnosing schizophrenia and to various socioeconomic and socioanamnestic variables in a Canadian sample of 107 schizophrenics diagnosed using the DSM-III criteria. Using the criterion of statistical significance of p. &lt; 01 (2-tailed), there were only three significant relationships, all of which were weak (r. &lt; 35), and none of which involved birth-order. Those patients with more siblings less often reported ideas of reference but more frequently reported problems with an excessively slow flow of thoughts and problems concentrating and they also responded better to fluphenazine treatment.

Idazoxan, an ??2 Antagonist, Augments Fluphenazine in

Idazoxan, a selective α2-adrenergic antagonist, was added to stable doses of fluphenazine treatment in six patients with schizophrenia who participated in a double-blind, placebo-controlled pharmacologic study. Compared with fluphenazine alone, combining idazoxan (mean dose, 120 mg/day) with fluphenazine (mean dose, 28 mg/day) resulted in a significant decrease in Brief Psychiatric Rating Scale total symptoms (p < 0.05). Symptom ratings returned to baseline upon idazoxan discontinuation. No significant effects of idazoxan were observed on fluphenazine levels in plasma or on extrapyramidal symptoms. These pilot data are compatible with the notion that increased noradrenergic neurotransmission may enhance the therapeutic effects of typical neuroleptics in schizophrenia.

Comparison of MK-801 and apomorphine induced stereotypic behaviours

Dopamine agonists administered systemically produce an increase in striatal levels of acetylcholine (ACh). Possible development of postsynaptic dopamine receptor supersensitivity after neuroleptic treatment was studied by measurement of apomorphine (APO)-induced increase in ACh levels in the striatum and olfactory tubercle. Apomorphine-induced Stereotypic behaviour was also measured. Rats received a single subcutaneous injection of either sesame seed oil vehicle or fluphenazine (FLU) decanoate (10mg kg−1), a long-acting neuroleptic preparation. After 14 days, rats received APO intraperitoneally, in various doses (0.03–1.0 mg kg−1). Fifteen minutes later, brain tissue was rapidly fixed by microwave irradiation, dissected, and ACh levels determined by means of gas chromatography. Acetylcholine levels were 75nmol g−1 in olfactory tubercle and 70 nmol g−1 in striatum. Apomorphine treatment resulted in dose-dependent increases of ACh level in both regions. Apomorphine-induced increases were greater in rats pretreated with FLU than in controls. Using 0.1 mg kg−1 APO, the higher striatal ACh-elevating effect found 14 days after FLU treatment was also present 21 days, but not 27 days after FLU treatment. At 21 days after subcutaneous injection, 0.25 mg kg−1 APO induced significantly greater Stereotypic behaviour in FLU-treated rats than in controls. Thus. FLU treatment led to an apparent temporary supersensitivity of APO-induced increases in ACh levels and stereotypic behaviour.