Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0085580 (essential hypertension)
 14,686 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A study of physician attitudes on biofeedback was conducted among members of the Harris County Medical Society, Harris County, Texas. The sample was drawn to match the proportionate representation in the society by speciality. Findings indicated that over 62% of the respondents had little knowledge of biofeedback, over 86% did not use biofeedback in their practice, 21.7% referred patients for biofeedback, and 47.1% were undecided whether insurance coverage should be provided. For specific disorders, adjunct treatment was the most recommended category for migraine and muscle contraction headaches, relaxation training for anxiety and tension, pain management, and essential hypertension. Responses were also analyzed by speciality category.
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PMID:A study of physician attitude on biofeedback. 704 12

A case of "effort thrombosis" of the subclavian vein which occurred in a young woman with severe thrombotic risk factors is reported. The manifestations of this syndrome are summarized, and recent concepts regarding the management of subclavian vein obstruction are discussed. The 33 year old woman was admitted with a 3 day history of rapidly increasing pain and swelling of her right upper extremity and right breast. She recalled no previous trauma but did indicate that her vocation required frequent exertion of her right (dominant) arm. The involved extremity exhibited easy fatigability with intermittent "tingling numbness" of the hand. She had been taking oral contraceptives (OCs) for 4 years. On admission she was smoking 2-3 packs of cigarettes daily with a 15 year smoking history. She had essential hypertension of 14 years duration which was treated with a thiazide diuretic. On physical examination, the patient's right breast was found to be twice the size of the left and exhibited tenderness, peau d'orange appearance, and superficial venous prominence. The right upper extremity exhibited venous prominence and mottled cyanosis and was edematous with an upper arm circumference that was 2.5 cm greater than the left. The involved axilla was tender, with no palpable venous "cord" or enlarged lymph nodes. Adson's maneuver was negative. Noninvasive impedance plethysmography showed no evidence of obstruction to venous outflow in the upper or lower extremities, but venography taken with the arms abducted to 45 degrees showed complete thrombotic obstruction of the right subclavian vein (shown in a figure). At first the patient was treated conservatively with bedrest, arm elevation, discontinuation of OCs, and heparinization. She became asymptomatic during the ensuing week, but a repeat venogram after 7 days of heparin therapy displayed complete obstruction of the right subclavian vein. The patient was discharged on warfarin sodium therapy which was continued for 5 months, during which time antithrombin 3 levels rose to 100% activity. During the year following hospitalization, the patient has experienced monthly episodes of mild aching in her right arm, unaccompanied by swelling or discoloration, following exertion of the extremity. Due to the fact that the etiology of effort thrombosis is now considered to be related to thoracic outlet compression, more emphasis is being placed on the use of phlebography to demonstrate compression points along the subclavian vein. Conservative management with anticoagulants continues to be the mainstay of therapy, but surgical treatment with early thrombectomy promises to decrease the chronic morbidity so common to this condition.
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PMID:"Effort thrombosis" of the subclavian vein associated with oral contraceptives. 731 65

The specificity of baroreceptor-dependent inhibition of pain reactions to electrical stimuli was investigated during induction of different emotional states in 27 subjects. Baroreceptors were stimulated through the PRES (Phase Related External Suction) technique, while emotions were induced by means of pleasant, neutral and unpleasant slides. The dependent variables were pain ratings, somatic evoked potentials (N150 and P260) recorded from Fz, Cz and Pz, and skin conductance response (SCR), while heart rate was recorded as a PRES requirement. Valence and arousal ratings were obtained in front of each slide. During suction (external baroreceptor activation) reduced pain ratings, cortical disfacilitation (from Pz, as revealed by N150) and lower SCR were found as compared to pressure (baroreceptor deactivation). Moreover, brain evoked potentials (N150 and P260) reflecting cortical inhibition were found under condition of baroreceptor stimulation during unpleasant slides, but not during pleasant or neutral ones: this result was found in the high blood pressure subjects only. Data showed also a valence effect on pain ratings: pain was evaluated to be higher during unpleasant slides, than neutral and pleasant ones. Results are discussed in the light of "baroreceptor reward" hypothesis, which proposes a learning mechanism for the development of essential hypertension.
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PMID:Baroreceptor cortical effects, emotions and pain. 779 Feb 90

Activating the arterial baroreceptors blunts pain sensation and produces other forms of central nervous system inhibition in animals. These effects may be important to blood pressure regulation but have not been rigorously verified in humans. We describe (i) a noninvasive behaviorally unbiased method for baroreceptor stimulation and (ii) the application of this method to measurement of baroreceptor-mediated attenuation of pain perception and of the Achilles tendon reflex. The findings are relevant to basic mechanisms of blood pressure stabilization and cardiovascular reactivity and may also have implications for noncompliance with antihypertensive medications and for the pathophysiology of essential hypertension.
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PMID:Central effects of baroreceptor activation in humans: attenuation of skeletal reflexes and pain perception. 802 81

The central autonomic network (CAN) is an integral component of an internal regulation system through which the brain controls visceromotor, neuroendocrine, pain, and behavioral responses essential for survival. It includes the insular cortex, amygdala, hypothalamus, periaqueductal gray matter, parabrachial complex, nucleus of the tractus solitarius, and ventrolateral medulla. Inputs to the CAN are multiple, including viscerosensory inputs relayed on the nucleus of the tractus solitarius and humoral inputs relayed through the circumventricular organs. The CAN controls preganglionic sympathetic and parasympathetic, neuroendocrine, respiratory, and sphincter motoneurons. The CAN is characterized by reciprocal interconnections, parallel organization, state-dependent activity, and neurochemical complexity. The insular cortex and amygdala mediate high-order autonomic control, and their involvement in seizures or stroke may produce severe cardiac arrhythmias and other autonomic manifestations. The paraventricular and other hypothalamic nuclei contain mixed neuronal populations that control specific subsets of preganglionic sympathetic and parasympathetic neurons. Hypothalamic autonomic disorders commonly produce hypothermia or hyperthermia. Hyperthermia and autonomic hyperactivity occur in patients with head trauma, hydrocephalus, neuroleptic malignant syndrome, and fatal familial insomnia. In the medulla, the nucleus of the tractus solitarius and ventrolateral medulla contain a network of respiratory, cardiovagal, and vasomotor neurons. Medullary autonomic disorders may cause orthostatic hypotension, paroxysmal hypertension, and sleep apnea. Neurologic catastrophes, such as subarachnoid hemorrhage, may produce cardiac arrhythmias, myocardial injury, hypertension, and pulmonary edema. Multiple system atrophy affects preganglionic autonomic, respiratory, and neuroendocrine outputs. The CAN may be critically involved in panic disorders, essential hypertension, obesity, and other medical conditions.
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PMID:The central autonomic network: functional organization, dysfunction, and perspective. 841 66

Split-half and test-retest reliabilities of heart-rate responses to a baroreceptor manipulation and an orthostatic maneuver were compared between subjects with either normal or elevated blood-pressure. Ten subjects showing elevated resting blood-pressure and II normotensive subjects participated in two experimental sessions, each including heart-rate recordings during baroreceptor manipulation and orthostatic challenge. Carotid baroreceptors were manipulated by applying the baroreceptor-specific phase-related external suction (PRES) technique. The orthostatic stimulation procedure (OSP) was a change of body position from lying to standing. Heart rate responses evoked by OSP failed to discriminate significantly between the groups either in the magnitude or the (test, retest) reliability measure. The PRES procedure also failed to discriminate with the conventional magnitude measure, but the reliability measures showed significant differences. Paradoxically, the high-blood-pressure group manifested the higher baroreceptor reliability. The present findings are consistent with the view that operant conditioning produces phasic blood-pressure increases. In this view, blood-pressure increases activate the arterial baroreceptors which, in turn, dampen pain and/or stress sensitivity. Individuals showing high consistency (reliability) in their cardiovascular responses are more likely to learn this form of conditioning, and hence to eventually increase their tonic blood-pressure. High reliability of cardiovascular responses may therefore constitute a risk for hypertension. Aside from such theoretical considerations, the findings indicate that less conventional dependent variables like reliability may be worth exploring in the search for the etiology of essential hypertension, and that, in this search, specificity (relative to baroreceptor function) is more important than the magnitude of the heart-rate changes that are produced.
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PMID:PRES- and orthostatic-induced heart-rate changes as markers of labile hypertension: magnitude and reliability measures. 877 Mar 73

A behavioral hypalgesia (increased response threshold to noxious stimuli) has been consistently, although not invariably, reported in spontaneous and experimental acute and chronic hypertension in the rat. Studies in human hypertension have also demonstrated a diminished perception of pain, assessed as pain thresholds or ratings. The sensitivity to painful stimuli correlated inversely with blood pressure levels, and this relationship extended into the normotensive range. Evidence in humans and rats points to a role of the baroreflex system in modulating nociception. In the rat, blood pressure-related antinociception may be due to attenuated transmission of noxious stimuli at the spinal level secondary to descending inhibitory influences that are projected from brain stem sites involved in cardiovascular regulation and that may depend on baroreceptor activation and/ or on a central "drive." Both endorphinergic and noradrenergic central neurons (the latter acting through postsynaptic alpha 2-receptors) have been shown to be involved, and other mediators probably also play a role. Functionally, blood pressure-related antinociception may represent an aspect of a more-complex coordinated adaptive response of the body to "stressful" situations. It is still uncertain whether in human essential hypertension hypalgesia is secondary to elevated blood pressure or whether both depend on some common mechanism. Studies on the effect of hypotensive treatment are too few to allow conclusions. According to one hypothesis, the reduction in pain perception caused by baroreceptor activation secondary to blood pressure elevation may represent a rewarding mechanism that may be reinforced with repeated stress and may be involved in the development of hypertension in some individuals. Hypertension-associated hypalgesia may have clinically relevant consequences, especially in silent myocardial ischemia and unrecognized myocardial infarction, both of which are more prevalent in hypertensive individuals.
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PMID:Hypertension-associated hypalgesia. Evidence in experimental animals and humans, pathophysiological mechanisms, and potential clinical consequences. 879 39

An association between a decreased responsiveness to varying painful stimuli and arterial hypertension both in animals and in humans has been documented. The relationship between essential hypertension and silent myocardial ischemia in coronary artery disease (CAD) populations is not well understood. The aims of this study in CAD patients with and without essential hypertension were (1) to determine dental pain threshold and reaction to tooth pulp stimulation and (2) to ascertain whether hypertensive CAD patients differ from normotensive ones in reactivity to pain. This study involved 182 patients who were affected by mild and moderate hypertension (G1) and 174 normotensive patients (G2). The inclusion criteria were reproducible exercise-induced myocardial ischemia, CAD documented at angiography, and dental formula suitable for pulp test. All patients underwent an ergometric stress test, coronary angiography, and pulp test. Our CAD hypertensive patients showed a lower prevalence of angina during daily life (64.8% in G1 versus 81.6% in G2, P<.05) and a higher incidence of exercise-induced silent myocardial ischemia (60.4% in G1 versus 48.8% in G2, P<.05) than the normotensive group. The mean anginal pain intensity, which was suffered both during spontaneous transitory episodes of ischemia and/or during acute myocardial infarction, was significantly lower in G1 than in G2 patients (P<.05). During pulp test, 31.8% of G1 and 13.7% of G2 referred no symptoms, even at the highest current intensity of 500 mA. The hypertensive patients with symptoms during pulp test had a higher mean dental pain threshold and lower mean threshold reaction and maximal reaction than did the normotensive symptomatic ones. In patients of both groups, a positive correlation between the mean maximal reaction during pulp test and the prevalence of angina during daily life was also found. In conclusion, patients with CAD and essential hypertension differ from normotensive CAD patients in reactivity to pain. Significantly higher pain thresholds and lower reactions to tooth pulp stimulation characterized patients with increased blood pressure values.
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PMID:Susceptibility to pain in hypertensive and normotensive patients with coronary artery disease: response to dental pulp stimulation. 936 88

Pain sensitivity decreases with increasing resting blood pressure. This blood pressure-pain interaction may be mediated by endogenous opioids which have been shown to affect both blood pressure and nociception. To test this hypothesis, we measured mean arterial blood pressure (MAP), central venous pressure (CVP), heart rate (HR), muscle sympathetic nerve activity (MSNA), serum catecholamines, and individual pain rating scales during 2 min periods of noxious mechanostimulation (skin fold pinching) in nine young (26 +/- 2 year), male normotensive (NT) subjects and in 12 age and weight matched males with borderline hypertension (BHT). Measurements were performed before and after the i.v. administration of naloxone (0.15 mg/kg) and placebo in a randomized double-blind cross-over trial. In the pre-naloxone trials, pain led to similar changes in MAP, CVP, MSNA and plasma catecholamines in the two groups except for a higher increase in HR in the BHT group as compared to the NT group (3 +/- 1 vs. 1 +/- 1 bpm; P < 0.005). Opioid blockade with naloxone increased MSNA responses to pain in the NT group (from 5 +/- 1 to 9 +/- 1 bursts/min, and, from 100 +/- 23 to 204 +/- 36 units/min, respectively; P < 0.05) but did not significantly affect the MSNA response to pain in the BHT group. Pain induced responses of MAP, CVP, and catecholamines were not altered by naloxone in either group. Overall, there was a highly significant inverse correlation between pain perception and resting blood pressure which was not significantly affected by naloxone. The BHT subjects exhibited a lower pain perception compared to the NT subjects (P < 0.005). Naloxone increased pain rating in the NT group (from 194 +/- 9 to 218 +/- 13; P < 0.005) but not in the borderline hypertensive group (160 +/- 8 vs. 168 +/- 10; P = 0.36). Except for a decreased HR response in the BHT group, placebo had no effect on the responses to pain. Our data do not indicate a major role of the endogenous opioid system for the blood pressure-pain interaction in man. Endogenous opioids affect pain perception and sympathetic nerve activity responses to pain in normotensive men but their activity seems to be attenuated in borderline hypertensive subjects. Therefore, the lower pain sensitivity in human essential hypertension is probably mediated by non-opioid mechanisms.
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PMID:Effects of naloxone on hemodynamic and sympathetic nerve responses to pain in normotensive vs. borderline hypertensive men. 967 23

For diagnosing cardiovascular emergencies, cardiologists mainly rely on physiological examinations. Biochemical laboratory examinations can facilitate emergency diagnosis and genetic diagnosis can facilitate a fundamental understanding of cardiovascular diseases. Recent progress in biochemical examinations for cardiovascular diseases includes measurement of troponin T, heart type fatty acid-binding protein, and LDL-cholesterol. Recent progress in genetic examinations includes analysis of mitochondrial DNA, obesity-related genes and single nucleotide polymorphisms. A safe and convenient system of collecting, transporting, and storing blood and other biological specimens, and the subsequent purification of genomic DNA from the stored specimens is available. Therefore, busy doctors and staff of clinical laboratory can plan subsequent DNA examinations without causing concern and pain. A recently reported human mutation of heterotrimeric G protein beta 3 subunit produces a gain-of-function G protein signaling abnormality. A common polymorphic base substitution, C825T, in the GNB3 gene is associated with an aberrantly spliced transcript lacking 123 nucleotides. A significant association of the T allele with essential hypertension or obesity has been suggested.
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PMID:[Progress in biochemical and genetic examinations in clinical laboratory of cardiovascular diseases]. 1080 12


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