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1.
Phys Rev Lett ; 108(12): 122002, 2012 Mar 23.
Article in English | MEDLINE | ID: mdl-22540573

ABSTRACT

The parity-violating (PV) asymmetry of inclusive π- production in electron scattering from a liquid deuterium target was measured at backward angles. The measurement was conducted as a part of the G0 experiment, at a beam energy of 360 MeV. The physics process dominating pion production for these kinematics is quasifree photoproduction off the neutron via the Δ0 resonance. In the context of heavy-baryon chiral perturbation theory, this asymmetry is related to a low-energy constant d(Δ)- that characterizes the parity-violating γNΔ coupling. Zhu et al. calculated d(Δ)- in a model benchmarked by the large asymmetries seen in hyperon weak radiative decays, and predicted potentially large asymmetries for this process, ranging from A(γ)-=-5.2 to +5.2 ppm. The measurement performed in this work leads to A(γ)-=-0.36±1.06±0.37±0.03 ppm (where sources of statistical, systematic and theoretical uncertainties are included), which would disfavor enchancements considered by Zhu et al. proportional to V(ud)/V(us). The measurement is part of a program of inelastic scattering measurements that were conducted by the G0 experiment, seeking to determine the N-Δ axial transition form factors using PV electron scattering.

2.
Phys Rev Lett ; 107(2): 022501, 2011 Jul 08.
Article in English | MEDLINE | ID: mdl-21797598

ABSTRACT

We have measured the beam-normal single-spin asymmetries in elastic scattering of transversely polarized electrons from the proton, and performed the first measurement in quasielastic scattering on the deuteron, at backward angles (lab scattering angle of 108°) for Q² = 0.22 GeV²/c² and 0.63 GeV²/c² at beam energies of 362 and 687 MeV, respectively. The asymmetry arises due to the imaginary part of the interference of the two-photon exchange amplitude with that of single-photon exchange. Results for the proton are consistent with a model calculation which includes inelastic intermediate hadronic (πN) states. An estimate of the beam-normal single-spin asymmetry for the scattering from the neutron is made using a quasistatic deuterium approximation, and is also in agreement with theory.

3.
Complement Ther Med ; 18(5): 206-14, 2010 Oct.
Article in English | MEDLINE | ID: mdl-21056844

ABSTRACT

OBJECTIVES: The objective of this study was to identify and describe online information about a complementary and alternative dietary intervention for cancer treatment, the Bill Henderson Protocol. DESIGN: A scoping method was applied to the Internet to identify information available on the Bill Henderson Protocol. Using the advanced search option, "Google," "Yahoo" and "Alta Vista" were used to search for the phrase "Bill Henderson Protocol." MAIN OUTCOMES: Information was found on 79 web pages. Most of the information took the form of personal commentaries and anecdotes, and included both positive and negative reports. Information was frequently found about different components of the protocol, but only one webpage provided complete details on what the regimen entails. Frequently, links were provided to Bill Henderson's website, where further protocol information could be found, including the opportunity to purchase his book. No empirical evidence was found. CONCLUSIONS: This study summarized information available on the Internet for the Bill Henderson Protocol an alternative dietary intervention intended to be used by people with cancer as a potentially curative treatment. The results of this study illustrate that new treatment interventions can be proposed, disseminated, discussed and used by consumers in advance of definitive evidence regarding efficacy and safety. This has implications for physician-patient interactions.


Subject(s)
Complementary Therapies , Information Services , Internet , Neoplasms/diet therapy , Humans , Information Dissemination
4.
Phys Rev Lett ; 104(1): 012001, 2010 Jan 08.
Article in English | MEDLINE | ID: mdl-20366359

ABSTRACT

We have measured parity-violating asymmetries in elastic electron-proton and quasielastic electron-deuteron scattering at Q2=0.22 and 0.63 GeV2. They are sensitive to strange quark contributions to currents in the nucleon and the nucleon axial-vector current. The results indicate strange quark contributions of approximately < 10% of the charge and magnetic nucleon form factors at these four-momentum transfers. We also present the first measurement of anapole moment effects in the axial-vector current at these four-momentum transfers.

5.
Curr Oncol ; 15 Suppl 2: s88-93, 2008 Aug.
Article in English | MEDLINE | ID: mdl-18769581

ABSTRACT

BACKGROUND: To ensure the safety and effectiveness of cancer management, it is important for physicians treating cancer patients to know whether their patients are using complementary and alternative medicine (CAM) and if so, why. OBJECTIVE: Here, we discuss the ethical and legal obligations of physicians to discuss cam use in an oncology setting, and we provide practical advice on how patient-provider communication about cam can be improved. RESULTS: Physicians have both ethical and legal obligations to their patients, including the obligation to respect patient autonomy. This latter obligation extends to use of CAM by patients and needs to be addressed beginning early in the patient-provider relationship. Because lack of education in this field and lack of time during patient consultations are barriers to talking with patients about cam, we provide resources to facilitate such discussions. These resources include suggestions on how to discuss the topic of cam and a wide range of information sources. CONCLUSIONS: Discussing CAM with patients is the physician's responsibility, and such discussion will facilitate evidence-based, patient-centred cancer care.

6.
J Res Natl Inst Stand Technol ; 110(3): 215-9, 2005.
Article in English | MEDLINE | ID: mdl-27308124

ABSTRACT

The NPDGamma γ-ray detector has been built to measure, with high accuracy, the size of the small parity-violating asymmetry in the angular distribution of gamma rays from the capture of polarized cold neutrons by protons. The high cold neutron flux at the Los Alamos Neutron Scattering Center (LANSCE) spallation neutron source and control of systematic errors require the use of current mode detection with vacuum photodiodes and low-noise solid-state preamplifiers. We show that the detector array operates at counting statistics and that the asymmetries due to B4C and (27)Al are zero to with- in 2 × 10(-6) and 7 × 10(-7), respectively. Boron and aluminum are used throughout the experiment. The results presented here are preliminary.

7.
Can J Neurol Sci ; 30(3): 201-5, 2003 Aug.
Article in English | MEDLINE | ID: mdl-12945941

ABSTRACT

BACKGROUND: Multiple sclerosis (MS) is one of the most common neurological diseases affecting young adults. The prevalence of MS in Alberta has been described as among the highest reported in the world, estimated at 217 per 100,000. Numerous anecdotal reports, and a few small empirical investigations have suggested that cannabis use may relieve the symptom experience of those with MS. The present study was undertaken to describe cannabis use by this patient group. Information on peoples' beliefs, practices and experiences related to use were investigated. METHODS: A questionnaire was mailed to a sample of 780 adults with MS in southern Alberta, Canada. RESULTS: Completed questionnaires were returned by 420/673 eligible subjects (response rate 62%). Mean sample age was 48 years and 75% were women. Respondents ranged from mildly to severely impaired. The majority of respondents (96%) was aware cannabis was potentially therapeutically useful for MS and most (72%) supported legalization for medicinal purposes. Forty-three percent had tried cannabis at some point in their lives, 16% for medicinal purposes. Symptoms reported to be ameliorated included anxiety/depression, spasticity and chronic pain. Reasons given for not trying cannabis were the fact that it is an illegal substance, concern about side effects and lack of knowledge on how to obtain it. CONCLUSIONS: Subjective improvements in symptom experience were reported by the majority of people with MS who currently use cannabis. Further evaluation of this substance is warranted.


Subject(s)
Cannabis , Multiple Sclerosis/drug therapy , Phytotherapy , Plant Preparations/therapeutic use , Adult , Attitude to Health , Cannabis/adverse effects , Female , Humans , Legislation, Drug , Male , Middle Aged , Multiple Sclerosis/psychology , Phytotherapy/adverse effects , Plant Preparations/adverse effects , Surveys and Questionnaires , Treatment Outcome
8.
Phys Rev Lett ; 87(27 Pt 1): 272301, 2001 Dec 31.
Article in English | MEDLINE | ID: mdl-11800873

ABSTRACT

The parity-violating longitudinal analyzing power, A(z), has been measured in pvectorp elastic scattering at an incident proton energy of 221 MeV. The result obtained is A(z) = [0.84+/-0.29(stat)+/-0.17(syst)]x10(-7). This experiment is unique in that it selects a single parity violating transition amplitude (3P2 - 1D2) and consequently directly constrains the weak meson-nucleon coupling constant h(pp)(rho). When this result is taken together with the existing pvectorp parity violation data, the weak meson-nucleon coupling constants h(pp)(rho) and h(pp)(omega) can, for the first time, both be determined.

9.
Psychooncology ; 9(4): 303-13, 2000.
Article in English | MEDLINE | ID: mdl-10960928

ABSTRACT

Partners of breast cancer patients are relied upon for support at a time when their own coping abilities are taxed by the challenge of cancer, yet few studies have investigated psychosocial interventions that include or target the patient's 'significant other'. Of the 118 consecutive patients approached, 36 patients and their partners participated in a randomized controlled trial of a brief psychoeducational group program for partners only. Psychometric instruments (including the Profile of Mood States (POMS), the Index of Marital Satisfaction (IMS) and DUKE-UNC Functional Social Support Scale (FSSS)) were administered pre-test, post-test and at 3 months follow-up. The Mental Adjustment to Cancer Scale (MAC) was also completed by patients. Three months after the intervention, partners had less mood disturbance than did controls. Patients whose partners received the intervention reported less mood disturbance, greater confidant support (CS) and greater marital satisfaction.


Subject(s)
Breast Neoplasms/psychology , Psychotherapy, Brief/organization & administration , Self-Help Groups/organization & administration , Spouses/education , Spouses/psychology , Adaptation, Psychological , Adult , Affect , Aged , Attitude to Health , Breast Neoplasms/therapy , Female , Health Knowledge, Attitudes, Practice , Humans , Male , Marriage/psychology , Middle Aged , Personal Satisfaction , Program Evaluation , Social Support , Surveys and Questionnaires
10.
Can Fam Physician ; 44: 1018-20, 1023-4, 1998 May.
Article in English | MEDLINE | ID: mdl-9612587

ABSTRACT

OBJECTIVE: To examine the knowledge, opinions, and referral behaviour of family physicians with respect to massage therapy and to explore factors associated with referral. DESIGN: A random, cross-sectional mailed survey. SETTING: Alberta family practices. PARTICIPANTS: Family physicians (n = 300). MAIN OUTCOME MEASURES: A self-report survey was developed for the study. This survey contained questions about sociodemographic and practice characteristics, perceived knowledge of massage therapy, opinions about the usefulness and legislation (government regulations) of massage therapy, and referral behaviour. RESULTS: Fifty-four percent of physicians (n = 161) completed the questionnaire. Sixty-eight percent of respondents indicated they had minimal or no knowledge of massage therapy. Despite this low level of knowledge, most (83%) believed massage therapy was a useful adjunct to their own practice. Moreover, 71% had referred patients to massage therapists and most (72%) perceived increasing demand from their patients for massage therapy. Approximately half of physicians surveyed supported government regulation of massage therapy. CONCLUSIONS: Physicians demonstrated a discrepancy between their knowledge of massage therapy and their opinions of, and referrals to, the profession. Physicians who referred patients to massage therapists generally held more positive opinions and had more knowledge of the discipline.


Subject(s)
Attitude of Health Personnel , Family Practice , Massage , Practice Patterns, Physicians' , Adult , Alberta , Cross-Sectional Studies , Female , Humans , Male , Referral and Consultation
11.
J Manipulative Physiol Ther ; 20(4): 235-40, 1997 May.
Article in English | MEDLINE | ID: mdl-9168407

ABSTRACT

OBJECTIVE: To examine changes in pain experienced, changes in functional ability and degree of patient satisfaction with chiropractic care. Patient characteristics influencing these parameters were also explored. DESIGN: A follow-up study consisting of a questionnaire to be completed at the beginning of treatment and a mailed questionnaire 6 wk later. SETTING: Non-random sample of 13 chiropractic practices in Calgary and Red Deer, Alberta, Canada. PATIENTS: Three hundred sixty-nine patients presenting with neck and/or back pain who saw a chiropractor for the first time or who had not seen a chiropractor for a period for 6 months before the first visit. RESULTS: Pain relief and changes in functional ability were greatest among patients whose initial pain or disability level was moderate or severe. No significant improvement was found among those whose initial level of pain or disability was mild. Pain relief and improved functional ability was greatest among those with an acute condition and those who saw no one other than the chiropractor during treatment. In addition, pain relief was highest among men, those who perceived themselves to be in good or excellent health and those who had completed treatment in 6 wk. Patients positively endorsed all items on the satisfaction questionnaire, indicating a high level of satisfaction with the care they received. Patients were most satisfied with access to chiropractic care and least satisfied with financial aspects. Improvement in pain and in back and neck disability were significantly related to general satisfaction. CONCLUSION: Based on these results, it seems that patients suffering from back and/or neck complaints experience chiropractic care as an effective means of resolving or ameliorating pain and functional impairments, thus reinforcing previous results showing the benefits of chiropractic treatment for back and neck pain.


Subject(s)
Back Pain/therapy , Chiropractic , Neck Pain/therapy , Outcome Assessment, Health Care , Follow-Up Studies , Humans , Patient Satisfaction , Surveys and Questionnaires
12.
Clin Invest Med ; 19(6): 453-60, 1996 Dec.
Article in English | MEDLINE | ID: mdl-8959355

ABSTRACT

OBJECTIVE: To develop a disease-specific quality-of-life scale for symptomatic cholelithiasis for use in clinical trials, and to evaluate its reliability, construct validity and responsiveness. DESIGN: Questionnaire. PARTICIPANTS: Health care professionals, patients with symptomatic cholelithiasis and their significant others. INTERVENTIONS: A 114-item questionnaire was developed from open-ended questions completed by the participants. Questions dealt with physical symptoms, activities of daily living, job performance, leisure activities, emotional factors, marital and sexual relations, support networks and financial situation. The questionnaire was administered by an interviewer to 50 subjects booked for elective cholecystectomy: frequency-importance products were calculated for each of the 114 items. A final shortened scale (the Gallstone Impact Checklist [GIC]) contained 41 items and was completed by patients with symptomatic cholelithiasis on two occasions, 4 to 6 weeks apart. RESULTS: The checklist requires 10 to 15 minutes to complete. Reliability of the questionnaire and its four subscales was assessed by Cronbach's alpha (overall questionnaire 0.88, pain 0.60, dyspepsia 0.73, emotional impact 0.78 and food and eating 0.84). Construct validity was established by comparison of questionnaire subscales with global ratings of physical and emotional health. Among subjects who reported a difference in their symptoms attributed to gallstones, there was a significant change in total GIC score and in each of the four subscales. Among patients who had undergone cholecystectomy, the absolute value of the effect size was 1.63. CONCLUSIONS: The GIC has content validity and appears to be a reliable, responsive measure of within-person change for subjects with symptomatic cholelithiasis.


Subject(s)
Cholelithiasis , Quality of Life , Adult , Cholelithiasis/physiopathology , Cholelithiasis/psychology , Dyspepsia , Eating , Emotions , Female , Food , Humans , Male , Middle Aged , Pain , Surveys and Questionnaires
13.
Hum Health Care Int ; 12(2): E9, 1996 Apr.
Article in English | MEDLINE | ID: mdl-14986601

ABSTRACT

Often the type of information collected in surveys of physicians' opinions about active euthanasia has not revealed their experiences and the rationale(s) they use in arriving at their opinions. This paper presents a qualitative analysis of comments made in a large survey of Alberta physicians' opinions about active euthanasia to identify issues physicians commented upon, and to explore the rationale(s) behind their opinions. This information adds an important qualitative perspective to the current debate about euthanasia and assisted suicide.


Subject(s)
Attitude of Health Personnel , Euthanasia, Active/ethics , Euthanasia, Active/psychology , Physicians/psychology , Alberta , Decision Making , Ethics, Medical , Euthanasia, Passive/ethics , Euthanasia, Passive/psychology , Humans , Palliative Care/ethics , Palliative Care/psychology , Quality of Life , Suicide, Assisted/psychology , Surveys and Questionnaires , Value of Life
14.
Can J Cardiol ; 11(9): 777-82, 1995 Oct.
Article in English | MEDLINE | ID: mdl-7585276

ABSTRACT

OBJECTIVE: To examine changes in health-related quality of life (HQOL) following coronary artery bypass surgery (CABS) in elderly patients and to compare patient ratings with proxy ratings. DESIGN: Descriptive, nonrandomized, prospective study. SETTING: Patients from a single primary care facility in a major urban centre within a one-year period. PATIENTS: All eligible patients undergoing CABS at the site within a one-year period were approached for study participation. The study sample consisted of 18 patients 65 years of age or older and 18 proxies at baseline. Fourteen patients and 13 proxies completed follow-up assessments. INTERVENTIONS: All patients underwent CABS. HQOL was studied using the Sickness Impact Profile (SIP) and the Psychological Well-Being Schedule (PGWB). MAIN RESULTS: Significant improvements were noted in physical, social and psychological functioning (P < 0.05). Proxies' reports provided good indications of patient functioning for these dimensions with significant differences found only for certain preoperative measures including the total SIP score and the Anxiety and Depression subscales of the PGWB (P < 0.05). CONCLUSIONS: Patients 65 years of age and older accrue improvements in HQOL following CABS. Such findings may influence the allocation and justification of various medical procedures. Proxy ratings closely reflected the patients' own ratings and may therefore be considered a reliable, alternate source of information.


Subject(s)
Coronary Artery Bypass , Quality of Life , Age Factors , Aged , Angina Pectoris/epidemiology , Angina Pectoris/etiology , Canada/epidemiology , Coronary Artery Bypass/psychology , Female , Humans , Male , Middle Aged , Postoperative Complications/epidemiology , Surveys and Questionnaires
15.
Peptides ; 14(6): 1299-308, 1993.
Article in English | MEDLINE | ID: mdl-8134313

ABSTRACT

Spinal and peripheral modulation of pentagastrin-stimulated gastric acid secretion by the pancreatic polypeptide-fold (PP-fold) peptides, neuropeptide Y (NPY), peptide YY (PYY), and pancreatic polypeptide (PP), in urethane-anesthetized rats was evaluated. Neuropeptide Y, PYY, and PP (400 pmol) were administered via intravenous (IV) and intrathecal (IT) injections. The alpha 2 antagonist, yohimbine, was used to evaluate the role of the alpha 2 adrenergic receptors in the modulation of pentagastrin-stimulated gastric acid secretion by NPY, PYY, and PP. Peptide YY and PP (IV) rapidly increased pentagastrin-stimulated gastric acid secretion. Peptide YY and PP (IT) increased pentagastrin-stimulated gastric acid secretion following administration into the thoracic (T8-T10) region of the spinal cord. The alpha 2 adrenergic receptor antagonist, yohimbine, did not modify the increases in pentagastrin-stimulated gastric acid secretion following PYY and PP (IV or IT) administration. Neuropeptide Y (IT) decreased pentagastrin-stimulated gastric acid secretion. However, in the presence of alpha 2 adrenergic receptor blockade, pentagastrin-stimulated gastric acid secretion was potentiated by NPY (IT) administration. Therefore, the inhibitory effect of NPY (IT) on pentagastrin-stimulated gastric acid secretion required the activation of alpha 2 adrenergic receptors in the spinal cord of rats. Mean arterial blood pressure (MAP) was increased immediately following NPY and PYY (IV) administration. During the same time period, PP (IV) decreased MAP in anesthetized rats. Mean arterial blood pressure was rapidly increased by NPY and PYY (IT) in anesthetized rats. The increase in MAP following PYY (IT) was partially attenuated in the presence of yohimbine.(ABSTRACT TRUNCATED AT 250 WORDS)


Subject(s)
Blood Pressure/physiology , Gastric Acid/metabolism , Neuropeptides/physiology , Peripheral Nerves/physiology , Spinal Cord/physiology , Animals , Blood Pressure/drug effects , Injections, Intravenous , Injections, Spinal , Male , Microinjections , Neuropeptide Y/physiology , Neuropeptides/administration & dosage , Pancreatic Polypeptide/physiology , Peptide YY , Peptides/administration & dosage , Peptides/physiology , Rats , Rats, Sprague-Dawley
16.
Can J Physiol Pharmacol ; 71(10-11): 768-75, 1993.
Article in English | MEDLINE | ID: mdl-8143235

ABSTRACT

The pancreatic polypeptide-fold (PP-fold) peptides neuropeptide Y (NPY), peptide YY (PYY), and pancreatic polypeptide (PP) (500 pmol/kg) increased duodenal and colonic intraluminal pressure of urethane-anesthesized rats following intravenous (i.v.) bolus injections. Increases in mean arterial pressure (MAP) accompanied the excitatory effects of NPY and PYY on gastrointestinal motility in these rats during the same time period. Atropine attenuated PYY's excitatory effect on duodenal pressure of rats. Excitatory effects of NPY, PYY, and PP (i.v.) on rat colon were not mediated via the muscarinic receptors. In the presence of hexamethonium, a nicotinic antagonist, PP (i.v.) increased colonic pressure to a greater extent than when administered alone. This observation suggested that PP had an inhibitory effect on colonic motility, which was not apparent as a result of the larger excitatory component. The nicotinic antagonist did not modulate the effects of peripherally administered NPY or PYY on duodenal or colonic motility in anesthetized rats. The Y2 receptor ligand, NPY (13-36) (i.v.) (500 pmol/kg), increased duodenal and colonic pressure in rats to the same extent as the full NPY molecule. Therefore, the peripheral effect of PYY and NPY on duodenal and colonic motility in rats may be mediated via Y2 receptors. NPY and PYY (i.v.) initially increased MAP, which then return to baseline values. Unlike NPY and PYY (i.v.) which produced short-term hypertensive effects PP (i.v. decreased MAP. Atropine did not attenuate the hypertensive effects of PYY and NPY (i.v.); however, the hypotensive effect of PP (i.v.) was blocked by atropine. The effects of the PP-fold peptides on MAP were not altered in the presence of hexamethonium.(ABSTRACT TRUNCATED AT 250 WORDS)


Subject(s)
Blood Pressure/drug effects , Gastrointestinal Hormones/pharmacology , Gastrointestinal Motility/drug effects , Neuropeptide Y/pharmacology , Pancreatic Polypeptide/pharmacology , Parasympathetic Nervous System/drug effects , Peptide Fragments/pharmacology , Peptides/pharmacology , Animals , Atropine/pharmacology , Colon/physiology , Duodenum/physiology , Hexamethonium Compounds/pharmacology , Male , Peptide YY , Rats , Rats, Sprague-Dawley , Receptors, Neuropeptide Y/drug effects
17.
Peptides ; 14(2): 153-60, 1993.
Article in English | MEDLINE | ID: mdl-8483795

ABSTRACT

Neuropeptide Y (NPY), peptide YY (PYY), and pancreatic polypeptide (PP) altered intraluminal pressure in the duodenum and colon of fasted anesthetized rats following intravenous bolus administration. There were rapid increases in intraluminal pressure of the duodenum and colon of anesthetized rats following peripheral injections of NPY, PYY and PP. Administration (IV) of NPY, PYY, and PP increased intraduodenal pressure +1.8, +3.2, and +3.7 mmHg compared to saline baseline. Prazosin, an alpha-2 adrenergic antagonist, did not alter the response of the duodenum of urethane-anesthesized rats to any of the PP-fold peptides following peripheral administration. Yohimbine, an alpha 2-adrenergic antagonist, attenuated the excitatory response of rat duodenum following NPY (IV) but did not alter the duodenal response to PP (IV). Intravenous NPY, PYY, and PP increased intracolonic pressure +2.0, +3.3, and +6.2 mmHg compared to saline baseline. In the presence of prazosin, an alpha 1-adrenergic antagonist, the intraluminal pressure of the colon increased +2.6, +2.4, and +8.1 mmHg compared to saline baseline by NPY, PYY, and PP (IV), respectively. In the presence of alpha 2-adrenergic blockade by yohimbine, NPY, PYY, and PP (IV) increased intraluminal pressure of the colon +4.2, +2.9, and +2.5 mmHg compared to saline baseline. The response of the duodenum to the excitatory effect of PYY (IV) was enhanced in the presence of yohimbine. Duodenal and colonic tone were modulated by the PP-fold peptides following peripheral administration. The alpha-adrenergic nervous system played only a minor role in the modulation of GI motility by the PP-fold peptides at peripheral sites.


Subject(s)
Gastrointestinal Motility/drug effects , Neuropeptide Y/pharmacology , Pancreatic Polypeptide/pharmacology , Peptides/pharmacology , Animals , Colon/drug effects , Colon/physiology , Duodenum/drug effects , Duodenum/physiology , Gastrointestinal Hormones/pharmacology , Gastrointestinal Hormones/physiology , Gastrointestinal Motility/physiology , Male , Neuropeptide Y/physiology , Pancreatic Polypeptide/physiology , Peptide YY , Peptides/physiology , Prazosin/pharmacology , Rats , Rats, Sprague-Dawley , Yohimbine/pharmacology
18.
Can J Physiol Pharmacol ; 71(2): 112-9, 1993 Feb.
Article in English | MEDLINE | ID: mdl-8319134

ABSTRACT

The pancreatic polypeptide-fold (PP-fold) peptides, peptide YY (PYY) and pancreatic polypeptide (PP) (200 pmol), increased duodenal intraluminal pressure following intrathecal (IT) administration into the thoracic (T8-T10) spinal cord of urethane-anesthetized rats. Neuropeptide Y (NPY), PPY, and PP (IT) increased colonic intraluminal pressure of rats. The excitatory effects of the PP-fold peptides, NPY and PYY, were accompanied by increases in mean arterial pressure (MAP) during the same time period followed by a decrease to hypotensive levels. There were no further alterations of duodenal or colonic pressure in rats during the hypotensive period. The effect of PP (IT) on MAP was characterized by a pattern of hypotension frequently followed by a hypertensive period. The modulation of duodenal and colonic pressure does not differ between the members of the PP-fold family of peptides; however, the effects of the different members of the PP-fold family of peptides on MAP were varied. The Y2 receptor ligand, NPY (13-36) (200 pmol) (IT), did not alter duodenal and colonic pressure or MAP in rats. Therefore, the effects of PYY and NPY in the thoracic spinal cord on duodenal and colonic motility may be mediated via Y1 (postjunctional) receptors. Atropine, a muscarinic antagonist, attenuated NPY's (IT) excitatory effect on colonic pressure but did not alter the MAP response to this peptide. Atropine did not modify PYY's (IT) regulation of duodenal and colonic intraluminal pressure. However, atropine did attenuate PPY's inhibitory effect on MAP.(ABSTRACT TRUNCATED AT 250 WORDS)


Subject(s)
Cholinergic Fibers/physiology , Colon/drug effects , Duodenum/drug effects , Gastrointestinal Motility/drug effects , Nervous System Physiological Phenomena , Neuropeptides/pharmacology , Spinal Cord/drug effects , Animals , Atropine/pharmacology , Blood Pressure/drug effects , Blood Pressure/physiology , Cholinergic Fibers/drug effects , Colon/physiology , Duodenum/physiology , Gastrointestinal Hormones/pharmacology , Gastrointestinal Hormones/physiology , Gastrointestinal Motility/physiology , Male , Nervous System/drug effects , Neuropeptide Y/pharmacology , Neuropeptide Y/physiology , Neuropeptides/physiology , Pancreatic Polypeptide/pharmacology , Pancreatic Polypeptide/physiology , Peptide Fragments/pharmacology , Peptide Fragments/physiology , Peptide YY , Peptides/pharmacology , Peptides/physiology , Rats , Rats, Sprague-Dawley , Receptors, Neuropeptide Y/drug effects , Receptors, Neuropeptide Y/physiology , Spinal Cord/physiology
19.
Peptides ; 13(4): 807-13, 1992.
Article in English | MEDLINE | ID: mdl-1437719

ABSTRACT

Neuropeptide Y, PYY, and PP (200 pmol) alter intraluminal pressure in the duodenum and colon of rats following their administration into the thoracic (T8-T10) region of the spinal cord. Neuropeptide Y decreases the tone of the duodenum and the colon following intrathecal (T8-T10) administration prior to an increase in tone to baseline or greater. There is no effect on intraluminal pressure of either the duodenum or the colon following intrathecal administration of NPY or PP into the lumbar (L4-L5) region of the spinal cord. Following intrathecal (T8-T10) administration of PYY and PP, increases in intraduodenal pressures are observed (+2.1 and +3.0 mmHg from saline baseline). Phasic contractions of the duodenum are increased following intrathecal administration of PYY into the thoracic spinal cord of rats. Neuropeptide Y, PYY, and PP increase intracolonic pressure +2.2, +3.3, and +3.7 mmHg from saline baseline, respectively. Phasic contractions of the colon are increased following PP intrathecal thoracic administration. Responsiveness of the duodenum or colon to the different ligands of the PP-fold peptide family in the absence of alpha-adrenergic blockade did not vary. The increases in intraluminal pressure of the duodenum and colon following intrathecal administration of the PP-fold peptides are attenuated by both alpha-1 adrenergic (prazosin) and alpha-2 adrenergic (yohimbine) blockade. There is a difference in responsiveness of the colon between the ligands of the PP-fold family in the presence of the alpha-2 adrenergic blockade. The findings of this study indicate that duodenal and colonic motility are modulated by the PP-fold peptides at thoracic spinal sites via alteration of sympathetic outflow.


Subject(s)
Gastrointestinal Motility/physiology , Neuropeptide Y/physiology , Pancreatic Polypeptide/physiology , Peptides/physiology , Spinal Cord/physiology , Animals , Colon , Duodenum , Gastrointestinal Hormones/physiology , Lumbosacral Region , Male , Peptide YY , Prazosin/pharmacology , Rats , Rats, Sprague-Dawley , Sympathetic Nervous System/drug effects , Sympathetic Nervous System/physiology , Thorax , Yohimbine/pharmacology
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