Influence of group selective reagents in tissues containing alpha- and beta-adrenoceptors.

N-ethylmaleimide which is known to react irreversibly with free -SH groups of protein when incubated with rabbit aorta (alpha-adrenoreceptor) or atria (beta-adrenoreceptor) markedly depressed the dose-response curves of norepinephrine isomers in the aorta but not in atria. Dithiothreitol, a reagent which reduces S-S linkages caused a parallel shift of the dose-response curves of both isomers to an equal degree in aorta. However, in atria the reagent drastically and selectively reduced the maximal effects of (+)-norepinephrine and dopamine. This selective alteration of the (+)-isomer by the reagent probably reflects the conformational changes at the beta-adrenoreceptor. The concentrations of N-ethylmaleimide and dithiothreitol required to alter the activity of norepinephrine isomers was higher for atria than for aorta. It may be that alpha-adrenoreceptors are more susceptible than the beta-adrenoreceptors on the -SH group selective reagents. In the highest concentration tested, two other reagents 2,4-dimethoxybenzylamine and N-acetylimidazole, did not influence the activity of the steroisomers on aorta. In the presence of dithiothreitol, the pharmacologic effects of a nonadrenoreceptor stimulant drug, histamine was potentiated on aorta (H1) and not on atria (H2). Results are discussed in the light of similarity and dissimilarity of adrenoreceptors as reflected by the group selective reagents and the stereoisomers.

Clinical phenomenology of mental disorders caused by Qigong exercise.

One hundred and nine patients with mental disorders caused by Qigong psychophysical exercise deviation are studied. These patients were divided into schizophrenic type (47 cases) and neurotic type (62 cases) and were analyzed by standard psychiatric rating scales and improved Minnesota multiphasic personality inventory (MMPI). The results show that patients with Qigong deviation presented abnormalities in perception, thinking, and behavior of varying degree. The clinical characteristics could not be classified into extent psychiatric disease units. Most of these patients manifested specific physical symptoms of Qigong deviation. The authors suggest that this kind of mild, benign mental disorder associated with the unique culture of our country be studied to contribute to the study of the classification of mental disorders. Qigong triggered disorders usually normalized during short term follow-up.

Attenuation of hemodynamic responses to laryngoscopy and tracheal intubation during rapid sequence induction: remifentanil vs. lidocaine with esmolol.

AIM: This study was designed to compare the effectiveness of remifentanil vs. a lidocaine-esmolol combination in blunting the hemodynamic response to laryngoscopy and intubation during rapid sequence induction using thiopental and rocuronium in normotensive patients. METHODS: Sixty-six patients with American Society of Anesthesiologists (ASA) physical status class I who required tracheal intubation for elective surgery were randomly assigned to one of two groups. Group R received 0.9% saline 10 ml and remifentanil 1 microg/kg. Group LE received lidocaine 1.5 mg/kg and esmolol 1.0 mg/kg. Anesthesia was induced with thiopental sodium 5 mg/kg, followed by rocuronium 1.0 mg/kg. Mean arterial pressure and heart rate were recorded at baseline, after induction, immediately after intubation and every minute for five minutes after intubation. RESULTS: Changes in mean arterial pressure over time between the two groups were significantly different (P<0.0001). The maximum pressor response was observed immediately after intubation, at which time the mean arterial pressure change from baseline in group LE (29.7%) (95% confidence interval [CI]: 116.1, 121.9) was higher than that in group R (4.4%) (95% CI: 92.9, 98.5) (P<0.0001). Two patients in group R and 15 patients in group LE developed hypertension (odds ratio [OR]: 0.064) (P<0.001). Changes in heart rate over time between the two groups were not significantly different (P=0.465). CONCLUSION: The results of this study show that remifentanil 1 mg/kg is more effective than the combination of lidocaine 1.5 mg/kg and esmolol 1 mg/kg for attenuating the hemodynamic responses to rapid sequence intubation.