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Query: UMLS:C0027497 (
nausea
)
23,468
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Effect of ethanol on adenosine 3', 5' cyclic monophosphate (
cAMP
), calcium (Ca) and magnesium (Mg) excretion was studied in controlled clinical conditions in man. Seven male volunteers served as their own controls. In 5 subjects
cAMP
excretion was primarily suppressed by ethanol. Ethanol appeared to have a biphasic effect on Ca excretion, an initial stimulation followed by a conservation phase. Mg excretion was stimulated by ethanol in 5 subjects. Subjects having
nausea
and vomitus and the most severe hangover symptoms had the lowest urinary Ca excretion and the lowest imitial
cAMP
excretion. Ca and Mg metabolism and the susceptibility of the body to the toxic effects of ethanol appeared to be interrelated.
...
PMID:Adenosine 3',5' cyclic monophosphate, calcium and magnesium excretion in ethanol intoxication and hangover. 23 65
Prostacyclin (PGI2) is known to cause vasorelaxation and inhibit platelet aggregation by receptor-mediated mechanisms. While cyclic (c) AMP is known to act as a second messenger for inhibition of platelet aggregation, vasorelaxation by hyperpolarization has been described only recently and may provide an explanation, in addition to stimulation of
cAMP
for the PGI2 mechanism of action on blood vessels. When PGI2 is infused into healthy volunteers it reduces blood pressure only at infusion rates that also cause significant side-effects, primarily,
nausea
, emesis, flushing, diaphoresis, and restlessness. In hypertensive patients blood-pressure responses are complex and are influenced to some extent by renin secretion. PGI2 stimulates renin secretion by a direct effect on the juxtaglomerular apparatus, and it also has an indirect effect by activating the sympathetic nervous system. Thus, it is useless as an antihypertensive agent even apart from its debilitating side-effects. Vascular PGI2 is synthesized endogenously by both the endothelial cells and the muscularis of arteries. While the endothelial cells undoubtedly synthesize large amounts of PGI2, the muscularis comprises a much larger tissue mass so that the overall synthesis is about equally distributed between the endothelial and muscle cells. In patients with pregnancy-induced hypertension and some patients with essential hypertension endogenous synthesis of PGI2 has been evaluated by measuring 2,3-dinor-6-keto-PGF1 alpha and has proved to be greatly reduced. Some drugs (thiazides, propranolol) have been shown to stimulate PGI2 synthesis, and inhibition of cyclooxygenase has been shown to reduce their antihypertensive effects. The effects of low- and high-dose aspirin on prostacyclin and thromboxane synthesis are discussed.(ABSTRACT TRUNCATED AT 250 WORDS)
...
PMID:[Prostacyclin in hypertension]. 149 51
Prostacyclin (PGI2) is known to cause vasorelaxation and inhibit platelet aggregation by receptor-mediated mechanisms. While cyclic (c)AMP is known to act as a second messenger for platelet aggregation, vasorelaxation by hyperpolarization has been described only recently and may provide an explanation, in addition to stimulation of
cAMP
, for the PGI2 mechanism of action on blood vessels. When PGI2 is infused into healthy volunteers it reduces blood pressure only at infusion rates that also cause significant side effects, primarily
nausea
, emesis, flushing, diphoresis and restlessness. In hypertensive patients blood pressure responses are complex and are influenced to some extent by secretion. PGI2 stimulates renin secretion by a direct effect on the juxtaglomerular apparatus, and also has an indirect effect by activating the sympathetic nervous system. Thus it is useless as an antihypertensive agent even apart from its debilitating side effects. Vascular PGI2 is synthesized endogenously by both the endothelial cells and the muscularis of arteries. While the endothelial cells undoubtedly synthesize larger amounts of PGI2, the muscularis comprises a much larger tissue mass so that the overall synthesis is about equally distributed between the endothelial and muscle cells. In patients with pregnancy-induced hypertension and some patients with essential hypertension, endogenous synthesis of PGI2 has been evaluated by measuring 2,3-dinor-6-keto-PGF1 alpha and has proved to be defective. Some drugs (cicletanine, thiazides, propranolol) have been shown to stimulate PGI2 synthesis, and inhibition of cyclooxygenase has been shown to abolish their antihypertensive effects. Whether stimulation of PGI2 synthesis affects the antihypertensive efficacy of these drugs is not yet known.
...
PMID:Prostacyclin in hypertension. 225 88
Among various oral antiplatelets, a combination of a novel prostacyclin analogue beraprost (BPT) and a potent phosphodiesterase inhibitor cilostazol (CLZ) may result in untoward clinical effects due to possible synergistic elevation of intracellular
cAMP
(cyclic adenosine 3',5'-monophosphate). Thereby, a clinical study of the combined administration of the two agents was attempted. Twelve healthy volunteers were assigned to take BPT/CLZ in the following schedule; BPT: 40 micrograms at day 1 and 120 micrograms t.i.d. from day 7 to 14, CLZ: 200 mg t.i.d. from day 3 to 14. At various time intervals, physical examination and blood collection for ex vivo platelet aggregation and determination of intraplatelet
cAMP
were performed. Throughout the observation period, no significant alteration in vital signs was observed. Seven out of 12 subjects experienced headache of a short duration accompanying facial flush in one and
nausea
in one, especially after ingestion of CLZ. All of these symptoms, probably caused by the vasodilating effect of the two agents, were of mild degree and no special treatment was required. Intraplatelet
cAMP
content was gradually but significantly increased to 9.84 +/- 4.59 pmol per 10(9) platelets at day 14 in comparison with the initial value (6.87 +/- 2.25 pmol). The platelet aggregability was significantly suppressed at various time intervals but no additive or synergistic inhibitory effect by the combined administration was noted. In conclusion, the combined administration of BPT/CLZ is safe at doses used in the study, though the beneficial clinical effect of the combined administration has yet to be elucidated.
...
PMID:Clinical evaluation on combined administration of oral prostacyclin analogue beraprost and phosphodiesterase inhibitor cilostazol. 759 55
Ears are special sense organs whose principal functions are hearing and maintaining equilibrium. Aminoglycoside antibiotics, erythromycin, polymyxin B, and cisplatin can affect either or both of these functions by binding with, injuring, and/or destroying special receptor cells associated with these functions. Severe hearing loss manifests itself as deafness, whereas loss of equilibrium will present as abnormal righting reflexes,
nausea
, and vomiting. Damage is proportional to levels of these ototoxins in the endolymphatic fluids. Evidence suggests that toxicity may be influenced by endolymphatic calcium concentrations, and levels of
cAMP
and cGMP are altered in specialized cochlear cells during ototoxicity, suggesting an additional mechanism for ototoxicity. The administration of salicylates and loop diuretics may potentiate the action of ototoxins, especially aminoglycoside antibiotics, probably by increasing the levels of these toxins in the endolymphatic fluid. Although many of these assessments have been made in laboratory animals, applicability may also be expected in small domestic animals, and extreme care should be taken in prescribing potentially ototoxic drugs to small animals. Cochlear damage from ototoxic compounds occurs initially in the cells detecting high-frequency sounds located at the lower basal region. In aging dogs and humans, this sensitivity of receptors in the lower basal region is enhanced. Early auditory damage is detectable by BAER and cochlear microphonic potentials. Vestibular responses can also be detected early as vestibular ocular reflexes and visual-vestibulo-ocular reflexes. Early detection is especially important because early changes can sometimes be reversible. Cavinton (apovincaminic acid) and fosfomycin represent examples of experimental agents being evaluated in laboratory animals for application as potential treatments to limit the ototoxicity associated with various drugs.
...
PMID:Ototoxicity in dogs and cats. 845 3
Our objective was to monitor serum and urine biochemical changes after oral sodium phosphate cleansing in a prospectively designed study. The study subjects were seven healthy, asymptomatic adults. Sodium phosphate 45 ml diluted in 45 ml water was given orally at baseline and 12 hr later. Calcium, ionized calcium, phosphorus, sodium, potassium, creatinine, and PTH were analyzed at 2, 4, 6, 9, 12, 14, 16, 18, 21 and 24 hr after the first challenge. Urinary calcium, phosphorus, sodium, potassium, and cyclic AMP were analyzed at baseline and every 2 hr after oral sodium phosphate. Blood pressure, pulse, and respiratory rate were recorded every 2 hr and symptom questionnaires using visual analog scales were completed. A marked rise in phosphorus (peak range 3.6-12.4 mg/dl, P < 0.001) and falls in calcium (P < 0.001) and ionized calcium (P < 0.001) were seen. Rises seen in PTH and urinary
cAMP
confirmed the physiologic significance of the biochemical effect. There were no significant changes in other serum and urine laboratory or clinical assessments. Reported significant symptoms included bloating, cramps, abdominal pain, and
nausea
. Significant hypocalcemia and hyperphosphatemia after oral sodium phosphate raises concern about its use in normal individuals. Oral sodium phosphate should not be administered in patients with cardiopulmonary, renal, or hepatic disease.
...
PMID:Biochemical effects of oral sodium phosphate. 867 96
cAMP-specific phosphodiesterase inhibitors display a range of activities in vitro and in vivo which suggest they may be useful in the treatment of inflammatory diseases. However, these compounds elicit a number of side-effects which may limit their therapeutic potential. Certain side-effects of PDE4 inhibitors such as emesis and gastric acid secretion are associated with their actions at a high affinity rolipram binding site (HARBS). In contrast, a number of anti-inflammatory actions of PDE4 inhibitors are better correlated with inhibition of PDE4 catalytic activity than with displacement of [3H] rolipram from HARBS. This suggests that native PDE4s in different cell-types can be discriminated pharmacologically. Although known to be associated with PDE4, the nature of HARBS is uncertain. The majority of evidence suggests it represents particular conformational states of PDE subtypes with which rolipram interacts with high potency (KD approximately 2 nM) (High-affinity PDE4, HPDE4). Rolipram is generally moderately or weakly active (IC50-200 nM-2000 nM) in inhibiting catalytic activity of the majority of crude, partially-purified or recombinant PDE4-preparations (Low-affinity PDE4, LPDE4). Solubilization or V/GSH treatment of particulate eosinophil PDE4,
cAMP
-dependent kinase activation of RNPDE4D3 and membrane association of HSPDE4A4 increase the potencies of some (e.g., rolipram) but not other (e.g., trequinsin) inhibitors. In eosinophils, the changes in enzyme properties brought about by solubilization result in a close correlation between the potency order of compounds in inhibiting
cAMP
hydrolysis and displacing [3H] rolipram from HARBS. The identification of distinct pharmacological PDE4 forms may have therapeutic consequences since it may be possible to synthesize potent inhibitors of LPDE4 with low affinity for HARBS which should, theoretically, be less emetic. Most inhibitors synthesized to date (rolipram, denbufylline nitraquazone, etc.) display high-affinity for HARBS but are much weaker in inhibiting
cAMP
hydrolysis. Other compounds (RP 73401, trequinsin, CDP 840) display slightly higher potency against LPDE4 or do not discriminate between the two putative PDE4 forms. Recently, inhibitors have been synthesized which are considerably more active against LPDE4 than HPDE4. Such compounds with appropriate pharmacokinetic properties may retain anti-inflammatory activity but have a reduced capacity to cause
nausea
and emesis and, consequently, have a wider therapeutic window than compounds currently undergoing clincial evaluation.
...
PMID:Proposal for pharmacologically distinct conformers of PDE4 cyclic AMP phosphodiesterases. 921 22
Nausea and vomiting are both elements of the system that evolved to defend the body against toxins accidentally ingested with the food. When they are induced by an ingested toxin, they are considered to be an appropriate response, but in many clinical settings (eg, anticancer chemotherapy, anesthesia and surgery, raised intracranial pressure) both responses are inappropriate in that the vomiting does not remove the cause and the
nausea
may lead to aversion to further treatment. Cyclic vomiting syndrome (CVS) is a particularly intense and prolonged example of inappropriate activation of this protective reflex. This review argues that insights into the pattern of emesis in CVS can be gained by examining the basic unit (quantum) of emesis, the emetic episode usually comprising retches followed by a vomit. Two (of several) possible mechanisms for the induction of the intense vomiting in CVS are discussed: (1) defects in intrinsic pathways (eg, opioid neurons) that may modulate the brain-stem emetic mechanisms, and (2) defects in the regulation of cellular mechanisms (eg,
cAMP
, ion channels) in cells at critical locations in the emetic pathway (eg, nucleus tractus solitarius, area postrema). If it is not possible to identify the causal mechanism of CVS, then will it be possible to treat CVS? This question is discussed in the context of the identification of universal or broad-spectrum antiemetic agents with recent preclinical studies with neurokinin-1 receptor antagonists reviewed to illustrate that such an approach is feasible.
...
PMID:Cyclic vomiting syndrome: timing, targets, and treatment--a basic science perspective. 1049 37
An increase of cyclic adenosine and guanosine monophosphate (
cAMP
and cGMP) level can be achieved by inhibition of phosphodiesterases (PDEs), which are the enzymes responsible for the conversion of these second messengers into the corresponding 5-monophosphate inactive counterparts. The high heterogeneity in PDE families and in their tissue distribution, as well as their different functional role, make these enzymes very attractive targets for medicinal chemists. The PDE 4 family is particularly abundant in immunocompetent cells, where an increase of
cAMP
leads to the inhibition of the synthesis and release of pro-inflammatory mediators, cytokines and active oxygen species. Moreover PDE 4 inhibitors are able to reduce bronchial smooth muscle tone in vitro and show bronchodilatory effects in vivo. Thus, the current therapy for asthma, which is based on a combination of beta(2) agonists and corticosteroids, could be replaced by treatment with PDE 4 inhibitors. This review mainly covers PDE 4 inhibitors structurally related to xanthines and Nitraquazone, which appear to be very attractive models for the synthesis of novel PDE 4 inhibitors potentially useful for the treatment of asthma, chronic pulmonary obstructive disease and some autoimmune diseases. These compounds could be devoid of the central side-effects (
nausea
, vomiting, headache) of the archetypal Rolipram, which hampered its development as a drug. The review also highlights the novel structural classes of PDE 4 inhibitors recently reported in the literature.
...
PMID:Phosphodiesterase 4 inhibitors, structurally unrelated to rolipram, as promising agents for the treatment of asthma and other pathologies. 1088 26
The phosphodiesterases (PDEs) are responsible for the hydrolysis of intracellular cyclic adenosine and guanosine monophosphate (
cAMP
and cGMP, respectively). They are classified into 11 major families (PDE1-11) and the type 4 phosphodiesterase (PDE4) is a
cAMP
-specific enzyme localized in airway smooth muscle cells as well as in immune and inflammatory cells. The PDE4 activity is associated with a wide variety of diseases some of which have been related to an inflammatory state, (e.g. asthma, chronic obstructive pulmonary disease (COPD), rheumatoid arthritis (RA)) while others have recently been connected to autoimmune pathology. Therefore, an intense effort toward the development of PDE4 inhibitors has been generated for the last decade. Unfortunately, the effects of prototype PDE4 inhibitors have been compromised by side effects such as
nausea
and emesis and the clinical use of those compounds is still limited. Several companies have focused on the design of a new generation of PDE4 inhibitors dissociating beneficial activity and adverse effects. This review highlights the recent data of the most advanced clinical candidates, the design and structure activity relationships of the recent structural series reported in the literature over the last two years, as well as recent advances in the multiple therapeutic indications of PDE4 inhibitors (a review with 375 references).
...
PMID:Recent advances in PDE4 inhibitors as immunoregulators and anti-inflammatory drugs. 1205 19
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