Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0030193 (pain)
 261,466 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

This study was designed to evaluate effects of enalaprilat, an angiotensin-converting enzyme inhibitor, on hemodynamic and hormonal responses during surgery at endotracheal intubation, incision, and limb-tourniquet inflation. Thirty patients undergoing limb procedures with general anesthesia (N2O/narcotic technique) and a pneumatic tourniquet were randomized to receive either preoperative enalaprilat (1.25 mg intravenously [i.v.] 20 min prior to induction) or intraoperative enalaprilat (0.625 mg i.v. at the onset of tourniquet-associated hypertension), with appropriate placebo controls. Arterial blood pressure and heart rate increased significantly in response to intubation in the placebo group. Although there were no significant differences in catecholamine levels, plasma renin activity was significantly increased at postincision in the preoperative-enalaprilat group versus the placebo group. This suggests that activation of the renin-angiotensin system may play a key role in mediation of intraoperative hemodynamic responses to endotracheal intubation. With respect to tourniquet hypertension, preoperative or intraoperative treatment with enalaprilat reduced neither the pressor response to tourniquet inflation nor the amount of enflurane subsequently required to control arterial blood pressure. These findings suggest that this response is mediated by pain pathways, and may be treated more effectively with anesthesia/analgesia.
 ...
PMID:Intraoperative hemodynamic, renin, and catecholamine responses after prophylactic and intraoperative administration of intravenous enalaprilat. 786 30

The feasibility, safety and effectiveness of percutaneous computed tomography-guided ethanol injection (PEI-CT) was investigated in a patient affected by aldosterone-producing adenoma (APA). A 42-year-old male patient with typical features of hyperaldosteronism presented a solitary left adrenal adenoma measuring 2 cm, with a normal contralateral gland, evidenced by both CT scan and adrenal [75Se-19]-nor-cholesterol scintigraphy. After normalization of potassium plasma levels, 4 ml of sterile 95% ethanol with 0.5 ml of 80% iothalamate sodium was injected. The procedure was completed in about 30 min. No severe pain or local complication was noted. Five hours after PEI, a fourfold and a twofold increase in aldosterone and cortisol plasma levels were observed, respectively. After 11 days on a normal sodium and potassium diet, normal potassium plasma levels and reduced aldosterone plasma levels were present, with reappearance of an aldosterone postural response. Plasma renin activity and aldosterone plasma levels normalized 1 month later, with reappearance also of a plasma renin activity postural response and maintenance of normal potassium plasma levels even on a high sodium and normal potassium diet. The patient has remained hypertensive, although lower antihypertensive drug dosages have been employed. After 17 months, normal biochemical, hormonal and morphological findings were still present. Thus, we suggest PEI-CT as a further alternative approach to surgery in the management of carefully selected patients with APA.
 ...
PMID:Percutaneous computed tomography-guided ethanol injection in aldosterone-producing adrenocortical adenoma. 788 78

The main focus of this paper is to show regulative interactions between cardiac index (CI) and renal blood flow (RBF) with various intravenous anaesthetics under steady state conditions. Several experimental series were carried out on dogs with the following anaesthetic doses (as given per hour and per kilogram body weight-h-1 x kg-1): fentanyl 50 micrograms, ketamine 4 and 10 mg, and thiopentone 10 and 20 mg. The basic anaesthesia used was halothane (0.7 vol.%) in N2O/O2 (ratio about 3:1), because renal function, renal autoregulation and responsiveness to renally effective drugs remain nearly unaltered by this anaesthetic procedure. The experimental set-up allowed separate evaluation of effects caused by basic anaesthesia, by intravenous anaesthetic under examination or by the combination of both. All physiological parameters, such as blood gas parameters, plasma electrolytes and intravasal volume were kept in normal range throughout the experiments. Under all anaesthetics studied, RBF reflects the situation of general metabolism especially of cardiac output, as long as sympathetic innervation of the kidneys remains unaltered. Especially the relationship between RBF and CI corresponds with regulative effects in situations without anaesthesia. Within the blood pressure range of autoregulation RBF is greater under ketamine than normal and smaller under fentanyl and etomidate, whereas all other anaesthetics applied show no effect on RBF. Functional "denervation" of the kidney by means of epidural anaesthesia is capable of terminating those effects caused centrally by opioids and transmitted by sympathetic nerves. Diuresis is increased by thiopentone and by ketamine, whereas fentanyl reduces it. The activity of the plasma renin level does not correspond with the degree of renal vascular resistance. The effect of each anaesthetic drug on RBF has principally to be taken as regulative adaptation to altered circulatory conditions. Increasing plasma renin levels are mainly a compensatory reaction following a decline in arterial blood pressure due to anaesthesia induced sympathicolysis. With regard to renal function, the additional use of epidural anaesthesia (functional "denervation" of the kidney) can be recommended especially for highly invasive surgical procedures to antagonize reduction of RBF, which is often induced sympathetically by pain or by commonly used anaesthetic drugs.
 ...
PMID:[Interactions between renal and general hemodynamics in fentanyl, droperidol, ketamine, thiopental and in peridural anesthesia--animal studies]. 852 61

The study was performed proceeding from the hypothesis that pain proneness in chronic pain disorder (CPD) is a result of alterations in central mechanisms regulating pain sensations. To elucidate the function of the central renin-angiotensin system, the levels of angiotensin-converting enzyme (ACE) and arginine vasopressin (AVP) in cerebrospinal fluid (CSF) and peripheral blood were measured in 15 CPD patients and 19 healthy controls. Plasma AVP levels (p = .01) as well as the serum osmolality (p = .01) were significantly higher in the CPD group. No significant differences in CSF ACE levels were found. AVP is a stress-related peptide, but central antinociceptive effects have also been reported. Elevated plasma AVP levels possibly may constitute a response to chronic stress.
 ...
PMID:Elevated plasma vasopressin and normal cerebrospinal fluid angiotensin-converting enzyme in chronic pain disorder. 891 58

1. The haemodynamic effects of different narcotic agents have been tested in healthy rats and in rats with cirrhosis. 2. Pentobarbital suppresses the sympathetic nervous system. Susceptibility to ketamine is unpredictable, leading to both insufficient pain relief and narcosis related mortality. The combination diazepam-fluanisone induces profound hypotension. After insertion of catheters, awake, freely moving rats are stable and not distressed. This allows repeated measurements after manipulation. Moreover, procedure-related mortality is low and rats have a better stress response. 3. In the awake animal, arterial pressure is 126 +/- 10 for healthy animals, and 111 +/- 16 and 102 +/- 10 mmHg for cirrhotic animals without and with ascites, respectively (P = 0.018). The respective values for portal pressure are 6.9 +/- 1.4, 11.6 +/- 2.5 and 16.2 +/- 2.9 mmHg (P = 0.0001). After a bleeding, arterial pressure is better preserved than portal pressure in the three groups (P < 0.0001). Plasma volume in cirrhotic rats exceeds that of healthy rats. Plasma renin activity, aldosterone and catecholamines do not differ between the groups studied. In cirrhotic rats with and without ascites, glomerular filtration rate tends to be higher (P = 0.12), renal plasma flow is elevated (P = 0.001) and filtration fraction is lower (P = 0.002) than in healthy rats. 4. In conclusion, haemodynamic experiments in the cirrhotic rat should be performed in the awake rat. Arterial hypotension, impaired filtration fraction, enlarged plasma volume and portal hypertension are present in cirrhosis before the development of ascites. This can as well be explained by splanchnic pooling of blood, as by peripheral vasodilatation. The decrease in portal pressure with preserved arterial pressure after a bleeding protects cirrhotic rats from ongoing variceal bleeding.
 ...
PMID:Effect of narcotic agents and of bleeding on systemic and renal haemodynamics in healthy and CCl4-treated cirrhotic rats. 949 92

Exposure to hostile conditions initiates the secretion of several hormones, including corticosterone/cortisol, catecholamines, prolactin, oxytocin, and renin, as part of the survival mechanism. Such conditions are often referred to as "stressors" and can be divided into three categories: external conditions resulting in pain or discomfort, internal homeostatic disturbances, and learned or associative responses to the perception of impending endangerment, pain, or discomfort ("psychological stress"). The hormones released in response to stressors often are referred to as "stress hormones" and their secretion is regulated by neural circuits impinging on hypothalamic neurons that are the final output toward the pituitary gland and the kidneys. This review discusses the forebrain circuits that mediate the neuroendocrine responses to stressors and emphasizes those neuroendocrine systems that have previously received little attention as stress-sensitive hormones: renin, oxytocin, and prolactin. Anxiolytic drugs of the benzodiazepine class and other drugs that affect catecholamine, GABAA, histamine, and serotonin receptors alter the neuroendocrine stress response. The effects of these drugs are discussed in relation to their effects on forebrain neural circuits that regulate stress hormone secretion. For psychological stressors such as conditioned fear, the neural circuits mediating neuroendocrine responses involve cortical activation of the basolateral amygdala, which in turn activates the central nucleus of the amygdala. The central amygdala then activates hypothalamic neurons directly, indirectly through the bed nucleus of the stria terminalis, and/or possibly via circuits involving brainstem serotonergic and catecholaminergic neurons. The renin response to psychological stress, in contrast to those of ACTH and prolactin, is not mediated by the bed nucleus of the stria terminalis and is not suppressed by benzodiazepine anxiolytics. Stressors that challenge cardiovascular homeostasis, such as hemorrhage, trigger a pattern of neuroendocrine responses that is similar to that observed in response to psychological stressors. These neuroendocrine responses are initiated by afferent signals from cardiovascular receptors which synapse in the medulla oblongata and are relayed either directly or indirectly to hypothalamic neurons controlling ACTH, prolactin, and oxytocin release. In contrast, forebrain pathways may not be essential for the renin response to hemorrhage. Thus current evidence indicates that although a diverse group of stressors initiate similar increases in ACTH, renin, prolactin, and oxytocin, the specific neural circuits and neurotransmitter systems involved in these responses differ for each neuroendocrine system and stressor category.
 ...
PMID:Forebrain pathways mediating stress-induced hormone secretion. 988 35

Arthritis and hypertension are frequent comorbidities in the elderly hypertensive population. Nonsteroidal anti-inflammatory drugs are often used to relieve pain in arthritic patients but a side effect is sodium retention and consequent elevation of blood pressure (BP). The effect of dihydropyridine calcium blocking drugs is relatively independent of sodium intake, whereas the angiotensin-converting enzyme (ACE) inhibitors' effects can be blunted by a high-sodium diet. This study compared the effects of indomethacin with placebo in elderly patients with essential hypertension who had been controlled with amlodipine or enalapril. Indomethacin 50 mg twice daily or placebo was administered for 3 weeks in a double-blind crossover study to patients controlled with amlodipine or enalapril. The response was assessed by ambulatory BP measurement. Indomethacin raised BP and lowered pulse rates in patients taking enalapril but had little effect in patients receiving amlodipine. The difference caused by indomethacin between the two groups was 10.1/4.9 mm Hg increase in BP and a 5.6 beats/min fall in pulse in people taking enalapril. Addition of indomethacin to patients taking either drug caused a rise in weight and a fall in plasma renin. It is postulated that the effect is due to inhibition of prostaglandin synthesis, which causes sodium retention. In patients taking amlodipine, the fall in plasma renin ameliorates the effect of sodium retention on BP. In patients taking enalapril, plasma renin falls but this is not translated into an effect because of the blockage of converting enzyme. Thus, the full effect of sodium retention on BP is expressed. In patients treated with indomethacin, fewer patients may respond to ACE inhibitors. However, the major problem is the patient who intermittently takes indomethacin or other nonsteroidal anti-inflammatory drugs, which, if a person is treated by an ACE inhibitor causes BP to go out of control. In such patients amlodipine would appear to be a preferred choice to enalapril.
 ...
PMID:Effect of indomethacin on blood pressure in elderly people with essential hypertension well controlled on amlodipine or enalapril. 1149 4

The lipid mediator prostaglandin E2 (PGE2) has diverse biological activity in a variety of tissues. Four different receptor subtypes (EP1-4) mediate these wide-ranging effects. The EP-receptor subtypes differ in tissue distribution, ligand-binding affinity, and coupling to intracellular signaling pathways. To identify the physiological roles for one of these receptors, the EP1 receptor, we generated EP1-deficient (EP1-/-) mice using homologous recombination in embryonic stem cells derived from the DBA/1lacJ strain of mice. The EP1-/- mice are healthy and fertile, without any overt physical defects. However, their pain-sensitivity responses, tested in two acute prostaglandin-dependent models, were reduced by approximately 50%. This reduction in the perception of pain was virtually identical to that achieved through pharmacological inhibition of prostaglandin synthesis in wild-type mice using a cyclooxygenase inhibitor. In addition, systolic blood pressure is significantly reduced in EP1 receptor-deficient mice and accompanied by increased renin-angiotensin activity, especially in males, suggesting a role for this receptor in cardiovascular homeostasis. Thus, the EP1 receptor for PGE2 plays a direct role in mediating algesia and in regulation of blood pressure.
 ...
PMID:The prostaglandin E2 EP1 receptor mediates pain perception and regulates blood pressure. 1116 Jan 56

Because of the diversity of medical and social circumstances of women over 40, there are no general rules regarding contraceptive choices for them. Gynecological or general pathological conditions should be considered in selecting a method, as should harmful health habits such as alcoholism and smoking, and the habitual use of medications. Hormonal contraceptives are very effective and practical, and give indirect benefits such as regularization of the cycle and amelioration of brease disorder and dysmenorrhea, but they increase cardiovascular risks. The risk of death from myocardial infarct is multiplied by a factor of 34 for women over 40 who smoke. Pill use is associated with a modification of the serum lipids and a tendency to hypercoagulability and increased risk of thrombosis, as well as a deterioration of glucose tolerance and an increase of insulin secretion. The estrogen and progestin combined oral contraceptives (OCs) have opposing effects on lipid metabolism; the overall effect depends on the dosage, the compounds used, and the hormonal profile of the pill. Combined OCs cause an elevation of blood pressure that may appear immediately or progressively over time. Synthetic estrogens increase activity of the renin-angiotensin system, resulting in increased aldosterone levels, reduction of renal blood flow, and sodium retention. Smoking considerably increases vascular risk and is a contraindication to pill use after 35 years. In the absense of further study, it appears that OCs do not in general increase the risk of breast, endometrial, cervical, or ovarian cancer, and in some cases they reduce risk. Some physicians refuse to prescribe OCs to any patient over 40, but many others take a more flexible attitude. Absolute contraindications of OC use must be respected, and relative contrainidications suck as smoking, prediabetic status, and migraines become absolute for women over 40. Biphasic minipills may be the best choice because they combine effectiveness, small dose, and an equilibrated hormonal climate. Women over 40 who are multiparous, who desire no more children, who have no genital anomalies, and who have a stable conjugal life may be ideal candidates for IUDs. IUDs are effective and avoid many shortcomings of OCs. Their complications of perforation, ectopic pregnancy, and infection are infrequent and their possible impact on fecundity is less important in this group. Bleeding and pain are the main disadvantages, but pregesterone-releasing IUDs may reduce the volume of bleeding, combat endometrial hyperplasia and alleviate menstrual pain. Vaginal methods offer safe contraception to women for who other methods are contraindicated. Their effectivenes is less than that of pills or IUDs but still sufficient. Although sterilization is not legal in France except for some precise therapeutic in dications, it is a logical choice for premenopausal women in good health who have the desired number of children and a stable emotional life.
 ...
PMID:[Contraception for women over 40]. 1226 11

Vasovagal syncope is defined as a reflex loss of consciousness related to reaction to various stimuli as orthostatic stress, pain or emotions connected with loss of muscle postural tone. The aetiology of this disorder is still unknown. The imbalance between the parts of autonomic nervous system and other homeostasis-related systems as renin-angiotensin-aldosterone system, peptides as endothelin, neuropeptide Y, vasopressin, adrenomedullin and cAMP, adenosine and AMP can play an important role in the development of vasovagal syncope. In the first part of the paper the authors describe the mechanisms involved in the development of vasovagal reaction, pathophysiology of the head-up tilt test and the role of autonomic nervous system.
 ...
PMID:[Neurohumoral mechanisms for vasovagal syncopes. Part I]. 1286 5


<< Previous 1 2 3 4 5 6 7 8 9 Next >>