Articles: histamine.
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Systemic mastocytosis is a rare disorder characterised by the infiltration of many tissues by abnormal numbers of mast cells. Life-threatening episodes of bronchospasm and hypotension are common in response to a variety of triggers which cause mast cell degranulation. ⋯ Cardiovascular data, together with blood histamine levels and thrombin times, indicated that mast cell degranulation did not occur. A review of the current literature concerning mast cell disease as it relates to anaesthesia is presented and suggestions for the safe management of such cases are given.
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To determine if clinical concentrations of halothane have direct relaxant effects on airway smooth muscle, the authors compared dose-response curves to histamine in the control state (thiopental) and during halothane anesthesia (1.0 and 1.5 MAC), in six basenji-greyhound (BG) dogs untreated and pretreated with atropine aerosols (10 mg X ml-1). Pulmonary resistance (RL) and dynamic compliance (Cdyn) were continuously monitored. Baseline airway tone was not significantly different during thiopental, halothane (1.0 MAC and 1.5 MAC), and after atropine aerosol administration. ⋯ There was no significant differences in the extent of antagonism of histamine-related bronchoconstriction between halothane (1.0 MAC and 1.5 MAC) and the atropine aerosol. Moreover, in four dogs halothane anesthesia in the presence of atropine offered no additional protection compared with atropine alone. Because the protection afforded by halothane was not greater than that of atropine pretreatment alone, and the addition of halothane to atropine failed to increase the protection, it is concluded that block of vagal reflexes was the major action of halothane responsible for the attenuation of histamine-induced bronchoconstriction.
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Clinical Trial Controlled Clinical Trial
Tachyphylaxis to topical steroid measured by histamine-induced wheal suppression.
Ten healthy volunteers were studied to find out whether tachyphylaxis occurs on repeated application of topical steroids. The Singh and Singh modification of the Reddy and Singh (1976) technique was used. Fluocinolone acetonide cream (0.1%) under occlusion was applied daily for 14 days on the flexor aspect of the forearms. ⋯ The maximum wheal suppression, which gradually diminished, was observed on the 8th day. By the 14th day, there was practically total tolerance to topical steroid, which showed minimal suppression of histamine wheal formation. This confirms the occurrence of the phenomenon of tachyphylaxis by different experimental techniques.
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Bull Eur Physiopathol Respir · Jan 1986
Comparative StudyBronchial responsiveness in asthmatic children aged 3 to 8 years measured by forced pseudo-random noise oscillometry.
With the forced pseudo-random noise oscillation technique (FOT), resistance (Rrs) and reactance (Xrs) of the respiratory system can be measured simultaneously over a frequency spectrum of 2-26 Hz. As only passive cooperation of the child is needed, FOT is suitable for lung function measurements from the age of 2 1/2 years. Hence bronchial responsiveness can be measured in children who are not yet able to perform spirometry or flow-volume curves. ⋯ Threshold dose or provocative dose to histamine and methacholine showed a close correlation in asthmatic children aged 3.6 to 7.8 years. The 24 hour interval within-subject reproducibility of threshold dose and provocative dose to histamine in asthmatic children aged 3.9 to 8.5 years proved to be good. Bronchial responsiveness to histamine or methacholine measured by FOT was not influenced by baseline lung function or by bronchial smooth muscle tone.
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Cent Nerv Syst Trauma · Jan 1985
Comparative StudyChanges in norepinephrine and histamine in monkey spinal cords traumatized by weight drop and compression.
Changes in norepinephrine and histamine levels in the spinal cord of monkeys at 1/2, 2, and 4 hours after 200 g cm of contusion injury, 50 g of compression injury, and 2 hours of decompression following 4 hours of compression were studied in the traumatized and an adjacent nontraumatized segment. Norepinephrine levels were elevated in the traumatized segment at 1/2, 2, and 4 hours after contusion injury and in the adjacent nontraumatized segment at 1/2 hour. Compression of 1/2 and 2 hours caused elevation of norepinephrine in both the traumatized and nontraumatized segments. ⋯ Histamine content increased in the traumatized segment at 2 and 4 hours after contusion injury and in the adjacent nontraumatized segment at 2 hours. Compression injury did not change histamine levels, but decompression caused an increase. The possible influence of simultaneous changes in norepinephrine and histamine levels on the vessels following injury is discussed.