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1.
Respir Med ; 227: 107633, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38631527

ABSTRACT

BACKGROUND: Anxiety is common in patients with chronic obstructive pulmonary disease (COPD). However, there is little evidence available regarding gender differences, and severity of dyspnea in relation to anxiety in patients with COPD. AIMS: We examined gender differences and the association of dyspnea with anxiety in a cohort of patients with COPD prior to entering a pulmonary rehabilitation (PR) program. METHOD: We analyzed data from a prospective cohort of COPD patients who attended PR from 2013 to 2019 in Lytham, Lancashire, UK. Patients were aged 40 years or older with a post-bronchodilation forced expiratory volume in 1 s (FEV1) less than 80 % of the predicted normal value and FEV1/FVC (forced vital capacity) ratio less than 0.7. We assessed quality of life (QoL) using the Saint George's Respiratory Questionnaire (SGRQ), anxiety using the Anxiety Inventory for Respiratory disease (AIR), dyspnea using the modified Medical Research Council (mMRC) scale, and exercise capacity using the Incremental Shuttle Walk Test (ISWT). RESULTS: Nine hundred ninety-three patients with COPD (mean age = 71 years, FEV1/FVC = 58 % predicted, 51 % male) entered the PR program. Of these, 348 (35 %) had anxiety symptoms (AIR ≥8); of these 165 (47 %) were male and 183 (53 %) female, (χ2 = 3.33, p = 0.06). On logistic multivariate analysis, the following variables were independently associated with elevated anxiety: younger age (p < 0.001), female sex (p = 0.03), higher SGRQ-total score (p < 0.001) and high FEV1/FVC (p < 0.002). Dyspnea was associated with anxiety r = 0.25, p < 0.001. CONCLUSION: Over a third of COPD patients had clinically relevant anxiety symptoms with a higher prevalence in women than men. Anxiety was associated with younger age, female gender, and impaired QoL. Early recognition and treatment of anxiety in patients with COPD is worthy of consideration for those attending PR, especially women.


Subject(s)
Anxiety , Dyspnea , Pulmonary Disease, Chronic Obstructive , Quality of Life , Humans , Pulmonary Disease, Chronic Obstructive/rehabilitation , Pulmonary Disease, Chronic Obstructive/psychology , Pulmonary Disease, Chronic Obstructive/physiopathology , Pulmonary Disease, Chronic Obstructive/complications , Male , Female , Aged , Anxiety/psychology , Dyspnea/psychology , Dyspnea/physiopathology , Dyspnea/etiology , Middle Aged , Prospective Studies , Forced Expiratory Volume/physiology , Sex Factors , Exercise Tolerance/physiology , Vital Capacity/physiology , Severity of Illness Index , Surveys and Questionnaires
2.
Ann R Coll Surg Engl ; 94(5): 313-7, 2012 Jul.
Article in English | MEDLINE | ID: mdl-22943225

ABSTRACT

INTRODUCTION: On 7 July 2005 four suicide bombings occurred on the London transport systems. In some of the injured survivors, bone fragments were embedded as biological foreign bodies. The aim of this study was to revisit those individuals who had sustained human projectile implantation injuries as a result of the bomb blasts at all scenes, review the process of body parts mapping and DNA identification at the scene, detail the management of such injuries and highlight the protocols that have been put in place for protection against blood borne pathogens. METHODS: We retrospectively reviewed 12 instances of victims who sustained human body projectile implantation injuries. The Metropolitan Police and forensic scientists identified the human projectiles using DNA profiling and mapped these on the involved carriages and those found outside. All human projectiles included were greater than 3 cm(2). RESULTS: Twelve cases had human projectile implantation injuries. Of these, two died at the scene and ten were treated in hospital. Projectiles were mapped at three of the four bomb blast sites. Our findings show that victims within a 2m radius of the blast had human projectile injuries. Eight of the allogenic bony fragments that were identified in the survivors originated from the suicide bomber. All victims with an open wound should have prophylaxis against hepatitis B and serum stored for appropriate action against HIV and hepatitis C infection. CONCLUSIONS: All victims following a suicide bombing should be assumed to have human body projectile implantation injuries with blood products or bony fragments. All immediate care providers should receive prophylaxis against hepatitis B virus and appropriate action should be taken against HIV and hepatitis C infection.


Subject(s)
Blast Injuries/etiology , Bone and Bones , Foreign Bodies/etiology , Terrorism , Wounds, Penetrating/etiology , Blast Injuries/therapy , Bombs , Emergency Responders , Emergency Treatment/methods , Explosions , Foreign Bodies/therapy , HIV Infections/prevention & control , Hepatitis B , Hepatitis C/prevention & control , Humans , London , Suicide
3.
Water Res ; 40(20): 3719-24, 2006 Dec.
Article in English | MEDLINE | ID: mdl-17070569

ABSTRACT

Source determination of fecal contamination is imperative to efficiently reduce the fecal material load to environmental waters. This study developed primer pairs targeting three F+ RNA bacteriophages and a simple filtration sampling method to enumerate and identify coliphages in environmental waters. Water samples were collected seasonally for one year from the watershed of Table Rock Lake on the Arkansas-Missouri border in areas predisposed to fecal contamination. Collected samples were analyzed quantitatively with most probable number and plaque assays and qualitatively with reverse transcription-PCR. We demonstrated the usefulness of F+ RNA coliphages as an indicator of fecal contamination, but were unable to distinguish between human and non-human sources. F+ coliphage numbers in Table Rock Lake showed seasonal variation with the highest level of coliphage presence during the January sampling event.


Subject(s)
Coliphages/isolation & purification , Environmental Monitoring/methods , Feces/microbiology , RNA Phages/isolation & purification , Water Microbiology , Arkansas , Coliphages/genetics , Coliphages/growth & development , Fresh Water , Humans , Missouri , RNA Phages/genetics , RNA Phages/growth & development , RNA, Viral/genetics , Reverse Transcriptase Polymerase Chain Reaction , Viral Plaque Assay , Water Pollution/analysis
4.
Complement Ther Nurs Midwifery ; 6(2): 66-71, 2000 May.
Article in English | MEDLINE | ID: mdl-10844743

ABSTRACT

The intention of this paper is to examine recent published research in the field of reflexology and healthcare and consider the way forward for research work in reflexology. It will explore the various research approaches and methods, which have and could be used in answering questions about reflexology practice and outcomes for patients. The recommendations of the Foundation for Integrated Medicine Report (FIM 1997) with regard to conducting research and audit will be included in the paper. These are proposed here as a framework for both reviewing past studies and as guidance for future reflexology investigations. The authors themselves have conducted small reflexology studies and they will reflect on their experiences in analysing the research process. This paper does not aim to give a concise review of the literature to date but uses examples of recently published work to illustrate the issues that might confront researchers.


Subject(s)
Massage , Research/standards , Research/trends , Data Collection/standards , Health Care Surveys/standards , Humans , Research Design/standards
5.
Gastroenterology ; 118(3): 544-53, 2000 Mar.
Article in English | MEDLINE | ID: mdl-10702205

ABSTRACT

BACKGROUND & AIMS: Experimental colitis is associated with anorexia that is attenuated by treatment with an interleukin (IL)-1 receptor antagonist. Serotonin (5-hydroxytryptamine [5-HT]) is a potent inhibitor of feeding, and its release from the hypothalamus is stimulated by IL-1. We have tested the hypotheses that anorexia associated with experimental colitis results from increased activity of hypothalamic 5-HT neurons and that the increase in activity occurs secondary to an increase in availability of tryptophan, the precursor of 5-HT. METHODS: In vivo 5-HT release and regional hypothalamic 5-HT and tryptophan concentrations were measured in rats with 2,4,6,-trinitrobenzene sulfonic acid (TNBS)-induced colitis, healthy controls, and animals pair-fed to match the food intake of the colitic group. Food intake in the colitic group was assessed after depletion of brain 5-HT by p-chlorophenylalanine (PCPA). RESULTS: In the colitic group, release of 5-HT from the hypothalamic paraventricular nucleus (PVN) was 3-fold (P = 0.01) and 14-fold (P < 0.001) higher than in control and pair-fed groups, respectively. Concentrations of tryptophan were similar in each group in all hypothalamic regions. Food intake was significantly increased in the colitic group after PCPA treatment but was not restored to control values. CONCLUSIONS: In animals with TNBS-induced colitis, 5-HT release from the PVN is increased. The increase in food intake after depletion of brain 5-HT suggests that hypothalamic 5-HT contributes to anorexia but is not the only mediator. Increased 5-HT release in the colitic group was not driven by increased precursor availability.


Subject(s)
Anorexia/etiology , Colitis/complications , Hypothalamus, Middle/physiopathology , Serotonin/physiology , Amino Acids/blood , Animals , Colitis/blood , Colitis/metabolism , Colitis/physiopathology , Drinking/drug effects , Eating/drug effects , Fenclonine/pharmacology , Hydroxyindoleacetic Acid/metabolism , Hypothalamus/metabolism , Hypothalamus, Middle/metabolism , Hypothalamus, Middle/pathology , Male , Paraventricular Hypothalamic Nucleus/metabolism , Rats , Rats, Wistar , Serotonin/metabolism , Serotonin Antagonists/pharmacology , Tissue Distribution , Tryptophan/blood , Tryptophan/metabolism
7.
Complement Ther Nurs Midwifery ; 5(2): 42-5, 1999 Apr.
Article in English | MEDLINE | ID: mdl-10474346

ABSTRACT

An earlier paper in this series of three has detailed the background development and organization of a pilot complementary therapy service. The setting was a neuroscience ward with existing staff carrying out the treatments. Outcome measures including physiological indices and patient feedback were reported on in Part II (Dryden et al. 1999). This paper will now focus on both the records of the practitioner's reflections and the recurring themes of their monthly clinical supervision sessions. Subgroups of four patients with Guillain-Barre Syndrome (GBS) are discussed in detail, as they received the most number of treatments between them.


Subject(s)
Attitude of Health Personnel , Complementary Therapies/organization & administration , Guillain-Barre Syndrome/nursing , Nursing Process , Nursing Staff, Hospital/psychology , Nursing, Supervisory/organization & administration , Clinical Competence , Guillain-Barre Syndrome/psychology , Humans , Nursing Methodology Research , Pilot Projects , Thinking
8.
Horm Metab Res ; 31(6): 363-6, 1999 Jun.
Article in English | MEDLINE | ID: mdl-10437624

ABSTRACT

Leptin inhibits feeding, stimulates thermogenesis and decreases body weight. Serotonin reduces food intake when injected into the hypothalamus and may interact with other neurotransmitters in the control of appetite. We therefore investigated the effects of the serotonergic drug fluoxetine, which inhibits serotonin reuptake, on food intake and plasma leptin levels in lean and obese Zucker rats. Fluoxetine significantly reduced food intake in lean and obese rats, both acutely after a single injection (10 mg/kg) and during continuous subcutaneous infusion (10 mg/kg/day for 7 days). Plasma leptin levels were reduced after both 4 hours and 7 days of fluoxetine administration in lean and after 7 days in fatty rats (all p<0.01). We have previously suggested that serotonin may decrease food intake by inhibiting neuropeptide Y neurones, and we further suggest that it also inhibits leptin, possibly by an effect on white adipose tissue.


Subject(s)
Fluoxetine/pharmacology , Obesity/metabolism , Proteins/metabolism , Selective Serotonin Reuptake Inhibitors/pharmacology , Animals , Eating/drug effects , Leptin , Male , Obesity/blood , Obesity/physiopathology , Rats , Rats, Zucker
9.
Clin Sci (Lond) ; 96(3): 307-12, 1999 03.
Article in English | MEDLINE | ID: mdl-10029567

ABSTRACT

Leptin inhibits feeding and decreases body weight. It may act partly by inhibiting hypothalamic neurons that express neuropeptide Y, a powerful inducer of feeding and obesity. These neuropeptide Y neurons express the Ob-Rb leptin receptor and are overactive in the fatty (fa/fa) Zucker rat. The fa mutation affects the extracellular domain of the leptin receptor, but its impact on leptin action and neuropeptide Y neuronal activity is not fully known. We compared the effects of three doses of leptin given intracerebroventricularly and three doses of leptin injected intraperitoneally on food intake and hypothalamic neuropeptide Y mRNA, in lean and fatty Zucker rats. In lean rats, 4-h food intake was reduced in a dose-related fashion (P<0.01) by all intracerebroventricular leptin doses and by intraperitoneal doses of 300 and 600 microg/kg. Neuropeptide Y mRNA levels were reduced by 28% and 21% after the highest intracerebroventricular and intraperitoneal doses respectively (P<0. 01 for both). In fatty rats, only the highest intracerebroventricular leptin dose reduced food intake (by 22%; P<0. 01). Neuropeptide Y mRNA levels were 100% higher in fatty rats than in lean animals, and were reduced by 18% (P<0.01) after the highest intracerebroventricular leptin dose. Intraperitoneal injection had no effect on food intake and neuropeptide Y mRNA. The fa/fa Zucker rat is therefore less sensitive to leptin given intracerebroventricularly and particularly intraperitoneally, suggesting that the fa mutation interferes both with leptin's direct effects on neurons and its transport into the central nervous system. Obesity in the fa/fa Zucker rat may be partly due to the inability of leptin to inhibit hypothalamic neuropeptide Y neurons.


Subject(s)
Eating/drug effects , Hypothalamus/metabolism , Neuropeptide Y/metabolism , Obesity/physiopathology , Proteins/pharmacology , Animals , Body Weight/drug effects , Dose-Response Relationship, Drug , Injections, Intraperitoneal , Injections, Intraventricular , Leptin , Male , Obesity/metabolism , Proteins/administration & dosage , Rats , Rats, Zucker
10.
Complement Ther Nurs Midwifery ; 5(1): 15-8, 1999 Feb.
Article in English | MEDLINE | ID: mdl-10639979

ABSTRACT

In part I of this series of articles (Dryden et al. 1998) the authors detailed the background to a project offering hand and foot massage incorporating reflexology techniques. The following paper reports back on the findings and evaluation. Over a 4-month period a total of 61 recorded treatments were given to 18 in-patients. Each session was to last approximately 30 minutes and included recordings of physiological data as well as pre- and post comments from the patient. The six practitioners, who were already working within the ward setting in various capacities, were asked to record reflective comments after each treatment. This paper will conclude by discussing future recommendations. Part III of this series (CTNM 5: 2, 1999) will focus on a subgroup of patients within the study highlighting the experiences of both practitioners and patients.


Subject(s)
Foot , Hand , Massage/methods , Adolescent , Adult , Aged , Female , Holistic Nursing/methods , Humans , Male , Massage/nursing , Massage/psychology , Middle Aged , Patient Satisfaction , Pilot Projects , Program Evaluation
12.
Peptides ; 19(9): 1549-55, 1998.
Article in English | MEDLINE | ID: mdl-9864062

ABSTRACT

Hypoglycemia causes hyperphagia and weight gain, through unknown peripheral and central signals. We investigated the effect of hypoglycemia on NPY and leptin expression and the ability of leptin to inhibit hypoglycemia-induced hyperphagia. Acute hypoglycemia (60 U/kg SC insulin; n = 8) increased food intake (p < 0.01) compared with controls (n = 8). Insulin- and leptin-treated rats (300 microg/kg IP leptin; n = 8) had reduced hyperphagia (p < 0.05 vs. controls; p < 0.05 vs. insulin alone) and a 15% fall in NPY mRNA levels compared with controls (p < 0.01). Chronic hypoglycemia, (20-60 U/kg/day insulin; n = 8) increased food intake compared with vehicle-treated controls (p < 0.01). Leptin and insulin administration (300 microg/kg/day IP leptin; n = 8) reduced hyperphagia (p < 0.01 vs. controls, p < 0.05 vs. insulin alone), and NPY mRNA fell by 18% vs. controls (p < 0.01). We conclude that hypoglycemia-induced hyperphagia is not mediated by either a fall in leptin or an increase in hypothalamic NPY mRNA. Leptin can inhibit feeding in hyperphagic hypoglycemic rats, and this may partly be attributable to its inhibition of the NPY neurons.


Subject(s)
Arcuate Nucleus of Hypothalamus/metabolism , Hyperphagia/etiology , Hypoglycemia/complications , Neuropeptide Y/biosynthesis , Protein Biosynthesis , Acute Disease , Analysis of Variance , Animals , Blood Glucose/analysis , Body Weight , Chronic Disease , Eating , Hypoglycemia/chemically induced , Insulin/blood , Insulin/pharmacology , Leptin , Male , Models, Biological , Neuropeptide Y/genetics , Proteins/genetics , RNA, Messenger/analysis , Rats , Rats, Wistar
13.
J Endocrinol ; 157(1): 169-75, 1998 Apr.
Article in English | MEDLINE | ID: mdl-9614370

ABSTRACT

To evaluate the role of neuropeptide Y (NPY), a potent appetite stimulant, in controlling food intake and body weight, we investigated the use of antisense oligodeoxynucleotides (ODNs) to inhibit NPY gene expression in the hypothalamus. We compared the hypothalamic distribution of fluorescein-labelled ODNs administered intracerebroventricularly, and effects on food intake and NPY gene expression, of three different structural modifications of an antisense ODN sequence against NPY. Rats had either the antisense or missense ODNs (24 micrograms/day) or saline infused into the third ventricle by osmotic minipumps for 7 days. The unmodified phosphodiester ODN was not detectable in the hypothalamus after 7 days and had no effects on food intake. The phosphorothioate ODN was widely distributed throughout the hypothalamus but had nonselective effects, with similar changes in food intake and NPY mRNA levels in the antisense and missense groups, and was severely toxic. The propyl-protected ODN appeared to penetrate the hypothalamus well but had no antisense-selective effects on NPY mRNA levels or food intake. Antisense ODNs are increasingly used to inhibit gene expression in vitro and in intact animals. These negative findings underline the need for rigorous evaluation of any effects of antisense ODNs administered into the central nervous system, and raise doubts about the validity of this approach in physiological or pharmacological studies.


Subject(s)
Eating/drug effects , Gene Expression Regulation , Hypothalamus/metabolism , Neuropeptide Y/physiology , Oligonucleotides, Antisense/administration & dosage , Analysis of Variance , Animals , Cerebral Ventricles , Chromatography, High Pressure Liquid , Infusion Pumps, Implantable , Male , Microscopy, Fluorescence , Neuropeptide Y/genetics , RNA, Messenger/analysis , Rats , Rats, Wistar , Sensitivity and Specificity
14.
Complement Ther Nurs Midwifery ; 4(6): 156-9, 1998 Dec.
Article in English | MEDLINE | ID: mdl-10205410

ABSTRACT

The purpose of these papers is to describe and discuss the piloting and evaluation of an inpatient complementary therapy service. This was a single site case study without a control group and involving practitioners themselves collecting data, recording reflections on their own practice and engaging in monthly clinical supervision sessions. The service was aimed at providing treatments of hand and foot massage incorporating reflexology techniques for a total of 18 patients. In part 2 of this paper, an evaluation of the project will be presented including the findings of this pilot service from the perspective of both the patients and practitioners, and the analysis of some of the physiological data collected. Part 3 will focus on a subgroup of the patient cohort to illuminate the experience from both patient and practitioner perspective.


Subject(s)
Holistic Nursing/methods , Massage/methods , Massage/nursing , Nervous System Diseases/nursing , Education, Nursing, Continuing/organization & administration , Female , Holistic Nursing/education , Humans , Interior Design and Furnishings , Massage/psychology , Nervous System Diseases/psychology , Nursing Evaluation Research , Nursing Staff, Hospital/education , Nursing Staff, Hospital/psychology , Pilot Projects , Program Evaluation , Research Design
15.
Diabetes ; 46(3): 335-41, 1997 Mar.
Article in English | MEDLINE | ID: mdl-9032086

ABSTRACT

Leptin acts on the brain to inhibit feeding, increase thermogenesis, and decrease body weight. Neuropeptide Y (NPY)-ergic neurons of the hypothalamic arcuate nucleus (ARC) that project to the paraventricular nuclei (PVN) and dorsomedial nuclei (DMH) are postulated to control energy balance by stimulating feeding and inhibiting thermogenesis, especially under conditions of energy deficit. We investigated whether leptin's short-term effects on energy balance are mediated by inhibition of the NPY neurons. Recombinant murine leptin (11 microg) injected into the lateral ventricle of fasted adult Wistar rats inhibited food intake by 20-25% between 2 and 6 h after administration, compared with saline-treated controls (P < 0.05). Uncoupling protein mRNA levels in brown adipose tissue (BAT) rose by 70% (P < 0.01). Leptin treatment significantly reduced NPY concentrations by 20-50% (P < 0.05) in the ARC, PVN, and DMH and significantly decreased hypothalamic NPY mRNA levels (0.61 +/- 0.02 vs. 0.78 +/- 0.03 arbitrary units; P < 0.01). A second study examined changes in leptin during 5 days' intracerebroventricular NPY administration (10 microg/day), which induced sustained hyperphagia and excessive weight gain. In NPY-treated rats, leptin mRNA levels in epididymal fat were comparable to those in saline-treated controls (0.94 +/- 0.17 vs. 1.0 +/- 0.28 arbitrary units; P > 0.1), but plasma leptin levels were significantly higher (4.88 +/- 0.66 vs. 2.85 +/- 0.20 ng/ml; P < 0.01). Leptin therefore acts centrally to decrease NPY synthesis and NPY levels in the ARC-PVN projection; reduced NPY release in the PVN may mediate leptin's hypophagic and thermogenic actions. Conversely, NPY-induced obesity results in raised circulating leptin concentrations. Leptin and the NPY-ergic ARC-PVN neurons may interact in a homeostatic loop to regulate body fat mass and energy balance.


Subject(s)
Adipose Tissue, Brown/metabolism , Carrier Proteins/biosynthesis , Cerebral Ventricles/physiology , Feeding Behavior/drug effects , Hypothalamus/physiology , Membrane Proteins/biosynthesis , Neurons/physiology , Neuropeptide Y/metabolism , Neuropeptide Y/pharmacology , Protein Biosynthesis , Proteins/pharmacology , Adipose Tissue, Brown/drug effects , Animals , Cerebral Ventricles/drug effects , Hyperphagia , Hypothalamus/drug effects , Infusions, Parenteral , Ion Channels , Leptin , Male , Mitochondria/drug effects , Mitochondria/metabolism , Mitochondrial Proteins , Neurons/drug effects , Neuropeptide Y/administration & dosage , Obesity , Oligonucleotide Probes , Proteins/administration & dosage , RNA, Messenger/biosynthesis , Rats , Rats, Wistar , Recombinant Proteins/pharmacology , Transcription, Genetic/drug effects , Uncoupling Protein 1 , Weight Gain/drug effects
16.
Br J Pharmacol ; 122(7): 1405-10, 1997 Dec.
Article in English | MEDLINE | ID: mdl-9421288

ABSTRACT

1. The thiazolidinedione BRL 49653 (rosiglitazone) induces hyperphagia and weight gain in obese, insulin-resistant fatty Zucker rats but not in lean insulin-sensitive rats. We investigated whether these responses might involve neuropeptide Y (NPY), leptin and insulin. 2. BRL 49653 (1 mg kg(-1) day(-1), orally) was given for 7 or 20 days to fatty and lean Zucker and Wistar rats. 3. In lean rats of either strain, BRL 49653 had no effect on food intake, body weight, plasma insulin and corticosterone, NPY or NPY mRNA levels. 4. Fatty rats given BRL 49653 showed a 30% increase in food intake and accelerated body weight gain (both P<0.01) after 7 and 20 days, but without significant changes in regional hypothalamic NPY or NPY mRNA levels. 5. Plasma leptin levels were twice as high in untreated fatty Zucker rats as in lean rats (P<0.01), but were unaffected by BRL 49653 given for 20 days. However, BRL 49653 reduced insulin levels by 42% and increased corticosterone levels by 124% in fatty rats (both P<0.01). 6. Hyperphagia induced in fatty Zucker rats by BRL 49653 does not appear to be mediated by either a fall in circulating leptin levels or increased activity of hypothalamic NPYergic neurones. The fall in plasma insulin and/or rise in corticosterone levels during BRL 49653 treatment may be involved, consistent with the postulated role of these hormones in the control of food intake.


Subject(s)
Eating/drug effects , Hypoglycemic Agents/pharmacology , Hypothalamus/drug effects , Neuropeptide Y/drug effects , Proteins/drug effects , Thiazoles/pharmacology , Thiazolidinediones , Animals , Appetite Stimulants/metabolism , Body Weight/drug effects , Hyperphagia/chemically induced , Hypoglycemic Agents/administration & dosage , Hypothalamus/metabolism , Leptin , Male , Neuropeptide Y/metabolism , Proteins/metabolism , Rats , Rats, Wistar , Rats, Zucker , Rosiglitazone , Thiazoles/administration & dosage
17.
Eur J Pharmacol ; 340(2-3): 221-5, 1997 Dec 11.
Article in English | MEDLINE | ID: mdl-9537819

ABSTRACT

Hypothalamic neuropeptide Y containing neurones are overactive and may mediate hyperphagia in insulin-deficient diabetic rats, but the factors stimulating them remain uncertain. To determine the possible role of glucocorticoids, we investigated the effects of the glucocorticoid receptor blocker mifepristone (RU486) on food intake and regional hypothalamic neuropeptide Y concentrations in streptozotocin-diabetic rats. RU486 (30 mg/kg) or corn oil vehicle control was given orally for 3 weeks to diabetic rats. Food intake and neuropeptide Y levels in the hypothalamic arcuate and paraventricular nuclei were increased in untreated diabetic rat groups (P < 0.01), and though RU486 did increase plasma corticosterone levels (P < 0.01) it did not have any effect on either feeding or neuropeptide Y levels (P = NS). These negative findings suggest that glucocorticoids may not be responsible for increasing hypothalamic neuropeptide Y or for hyperphagia in insulin-deficient diabetes.


Subject(s)
Diabetes Mellitus, Experimental/metabolism , Hormone Antagonists/pharmacology , Hyperphagia/etiology , Hypothalamus/metabolism , Mifepristone/pharmacology , Neuropeptide Y/metabolism , Receptors, Glucocorticoid/antagonists & inhibitors , Animals , Blood Glucose/metabolism , Body Weight/drug effects , Diabetes Mellitus, Experimental/psychology , Drinking/drug effects , Eating/drug effects , Insulin/blood , Male , Rats , Rats, Wistar
18.
Brain Res ; 724(2): 232-7, 1996 Jun 17.
Article in English | MEDLINE | ID: mdl-8828573

ABSTRACT

Neurons containing serotonin (5-HT), a potent anorexic agent, come into contact with neuropeptide Y-ergic neurons, that project from the arcuate nucleus (ARC) to the paraventricular nucleus (PVN). NPY powerfully stimulates feeding and induces obesity when injected repeatedly into PVN. We hypothesize that 5-HT tonically inhibits the ARC-PVN neurons and that balance between the two systems determines feeding and energy homeostasis. This study aimed to determine whether central injection of the 5-HT synthesis inhibitor p-chlorophenylalanine (pCPA), which increases feeding, increased hypothalamic NPY and NPY mRNA levels. pCPA (10 mg/kg in 3 microliters) was administered into the third ventricle either as a single injection (n = 8) or daily for 7 days (n = 8). Control rats received a similar injection of saline. pCPA significantly increased food intake compared with controls after both single and repeated injections (P < 0.05). NPY levels were measured by radioimmunoassay in microdissected hypothalamic extracts. NPY levels in the acutely treated group were significantly increased in the paraventricular nucleus (PVN; by 41%, P = 0.01), anterior hypothalamic area (AHA; by 34%, P < 0.01) and lateral hypothalamic area (LHA; by 41%, P < 0.02). In the 7-day-treated group, NPY levels were also increased in the same areas, i.e. PVN (by 24%, P < 0.01), AHA (by 30%, P < 0.01) and LHA (by 38%, P = 0.01). There were no significant changes in the ARC or any other region or in hypothalamic NPY mRNA levels. pCPA administration increased NPY levels in several regions notably the PVN. This is a major site of NPY release, where NPY injection induces feeding. We suggest that the hyperphagia induced by pCPA is mediated by increased NPY levels and secretion in the PVN. This is further evidence for interactions between NPY and 5-HT in the control of energy homeostasis.


Subject(s)
Feeding Behavior/drug effects , Fenclonine/pharmacology , Hypothalamus/metabolism , Neuropeptide Y/metabolism , RNA, Messenger/biosynthesis , Serotonin Antagonists/pharmacology , Animals , Arcuate Nucleus of Hypothalamus/drug effects , Arcuate Nucleus of Hypothalamus/physiology , Blood Glucose/metabolism , Body Weight/physiology , Corticosterone/blood , Fenclonine/administration & dosage , Hypothalamus/drug effects , Insulin/blood , Male , Neural Pathways/cytology , Neural Pathways/physiology , Neuropeptide Y/biosynthesis , Paraventricular Hypothalamic Nucleus/drug effects , Paraventricular Hypothalamic Nucleus/physiology , Radioimmunoassay , Rats , Rats, Wistar
20.
Neuroscience ; 72(2): 557-66, 1996 May.
Article in English | MEDLINE | ID: mdl-8737424

ABSTRACT

Evidence suggests that serotonin and neuropeptide Y neurons in the hypothalamus, which respectively inhibit and stimulate food intake, may interact to control energy homoeostasis. We therefore investigated the effects of fluoxetine, which inhibits serotonin reuptake, on food intake and the activity of the neuropeptide Yergic arcuato-paraventricular projection in lean Wistar and Zucker rats. We also studied its effects in obese Zucker rats, in which obesity is postulated to be due to overactivity of the arcuato-paraventricular projection. Fluoxetine significantly reduced food intake in lean and obese rats, both during continuous subcutaneous infusion and (10 mg/kg/day for seven days) and acutely after a single injection (10 mg/kg). Fluoxetine also significantly reduced neuropeptide Y levels in the paraventricular nucleus, a major site of neuropeptide Y release which is highly sensitive to the appetite-stimulating actions of neuropeptide Y. Push-pull sampling in lean and fatty Zucker rats showed that neuropeptide Y secretion in the paraventricular nucleus was significantly reduced after acute fluoxetine treatment. Furthermore, seven days fluoxetine treatment prevented the significant increases in hypothalamic neuropeptide Y messenger RNA which were induced in lean rats by food restriction which precisely matched the hypophagia induced by the drug. We conclude that fluoxetine inhibits various aspects of the activity of the neuropeptide Yergic arcuato-paraventricular neurons, and suggest that reduced neuropeptide Y release in the paraventricular nucleus may mediate, at least in part, the drug's hypophagic action. We further suggest that serotonin may influence food intake and energy balance by inhibiting the arcuato-paraventricular projection, and that the two neurotransmitters may act together to regulate feeding and energy homoeostasis.


Subject(s)
Fluoxetine/pharmacology , Hypothalamus/metabolism , Neuropeptide Y/metabolism , Obesity/metabolism , Selective Serotonin Reuptake Inhibitors/pharmacology , Animals , Arcuate Nucleus of Hypothalamus/cytology , Arcuate Nucleus of Hypothalamus/drug effects , Arcuate Nucleus of Hypothalamus/metabolism , Autoradiography , Blood Glucose/metabolism , Body Weight , Eating/drug effects , Hormones/blood , Hypothalamus/cytology , Hypothalamus/drug effects , Male , Neural Pathways/cytology , Neural Pathways/drug effects , Neural Pathways/metabolism , Neurons/drug effects , Neurons/metabolism , Obesity/genetics , Paraventricular Hypothalamic Nucleus/cytology , Paraventricular Hypothalamic Nucleus/drug effects , Paraventricular Hypothalamic Nucleus/metabolism , RNA, Messenger/biosynthesis , Rats , Rats, Wistar , Rats, Zucker
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