Search results for "Halothane"

AFM study of interaction forces in supported planar DPPC bilayers in the presence of general anesthetic halothane

2006

International audience; In spite of numerous investigations, the molecular mechanism of general anesthetics action is still not well understood. It has been shown that the anesthetic potency is related to the ability of an anesthetic to partition into the membrane. We have investigated changes in structure, dynamics and forces of interaction in supported dipalmitoylphosphatidylcholine (DPPC) bilayers in the presence of the general anesthetic halothane. In the present study, we measured the forces of interaction between the probe and the bilayer using an atomic force microscope. The changes in force curves as a function of anesthetic incorporation were analyzed. Force measurements were in go…

Comparison of the ventilating and injection bronchoscopes.

1973

Multicentre evaluation of in vitro contracture testing with bolus administration of 4-chloro-m-cresol for diagnosis of malignant hyperthermia suscept…

2003

Background and objective The in vitro contracture test with halothane and caffeine is the gold standard for the diagnosis of susceptibility to malignant hyperthermia (MH). However, the sensitivity of the in vitro contracture test is between 97 and 99% and its specificity is 78-94% with the consequence that false-negative as well as false-positive test results are possible. 4-Chloro-m-cresol is potentially a more specific test drug for the in vitro contracture test than halothane or caffeine. This multicentre study was designed to investigate whether an in vitro contracture test with bolus administration of 4-chloro-m-cresol can improve the accuracy of the diagnosis of susceptibility to MH. …

Effect of Hyper- and Hypoventilation on CBF during Anesthesia

1969

Alexander and Wollman [1, 2, 4, 8], Harper [5] and McDowall and other investigators have published observations on CBF during anaesthesia in man and dog, when arterial pCO2 was altered by hyper- or hypoventilation.

Membrane Expression of Autoantigens on Mechanically and Enzymatically Isolated Hepatocytes

1986

Die Plasmamembranexpression von Leberzellmembran-Antigenen wurde mit indirekter Immunfluoreszenz (IF) und Immunelektronenmikroskopie (IELMI) an mechanisch und enzymatisch isolierten Kaninchenhepatozyten untersucht. 90 – 95 % der enzymatisch isolierten Hepatozyten, aber nur 40 – 60 % der mechanisch isolierten Hepatozyten waren intakt und vital. Eine Untergruppe der autoimmunen chronisch aktiven Hepatitis (CAH) weist zirkulierende Antikorper gegen ein mikrosomales Antigen aus Leber und Niere (LKM) auf. Die vermutete Membranexpression fur LKM-Antigene konnte durch unsere Untersuchungen mit IF und IELMI an vitalen Kaninchenhepatozyten nicht nachgewiesen werden. Der als Referenzantikorper verwen…

Putative role of nitric oxide synthase isoforms in the changes of nitric oxide concentration in rat brain cortex and cerebellum following sevoflurane…

2005

We have previously observed an increase in nitric oxide (NO) content in rat brain cortex following halothane, sevoflurane or isoflurane anaesthesia. This study was undertaken in order to determine whether isoform-specific nitric oxide synthase (NOS) inhibitors and inducers could modify these increases in NO contents. Rats were subjected to isoflurane and sevoflurane anaesthesia with concomitant administration of neuronal nitric oxide synthase (nNOS) inhibitor 7-Nitro-indazole (7-NI), inducible nitric oxide synthase (iNOS) inhibitor 2-amino-5,6-dihydro-6-methyl-4H-1,3-thiazine (AMT) or lipopolysaccharide. NO concentration in different organs was measured by electron paramagnetic resonance (E…

Dependence of hepatic gluconeogenesis on PO2: inhibitory effects of halothane

1987

The dependence of gluconeogenesis and O2 uptake on PO2 in isolated rat hepatocytes is presented. Maintenance of steady-state PO2 was achieved with an oxystat system (Biochem. J. 236: 765–769, 1986). O2 uptake showed a half-maximal (K0.5) value of 0.5 Torr PO2, whereas the glucose synthesis rate was half-maximal at 1.2 Torr PO2. Halothane at concentrations greater than 1 mM exerted a parallel inhibition of O2 uptake and glucose synthesis at all PO2 levels studied. In contrast, at halothane concentrations less than 1 mM, inhibition of glucose synthesis occurred only at less than 20 Torr PO2. At these low concentrations, halothane was without significant effects on cellular O2 uptake. In isol…

ANTI-ARRHYTHMIC EFFECT OF DEHYDROBENZPERIDOL IN DOGS

1971

SUMMARY The anti-arrhythmic activity of dehydrobenzperidol (DBP) was studied during halothane anaesthesia in dogs. Arrhythmias were provoked by single intravenous injections of catecholamines. Two groups of dogs were studied. One received norepinephrine and the odier epinephrine. The dose just sufficient to initiate arrirythmias was defined as the “threshold”. Electrocardiogram, blood pressure and heart rate were monitored. The principal findings were:— 1  The dog heart was “sensitized” to epinephrine and norepinephrine by halothane. 2  DBP did have an anti-arrhydimic action. A dose of 0.150 mg/kg roughly doubled the “threshold”. 3  DBP had significant alpha-adrenergic blocking properties. …

Capillary flow and diameter changes during reperfusion after global cerebral ischemia studied by intravital video microscopy.

2004

The reaction of cerebral capillaries to ischemia is unclear. Based on Hossmann's observation of postischemic “delayed hypoperfusion,” we hypothesized that capillary flow is decreased during reperfusion because of increased precapillary flow resistance. To test this hypothesis, we measured cerebral capillary erythrocyte velocity and diameter changes by intravital microscopy in gerbils. A cranial window was prepared over the frontoparietal cortex in 26 gerbils anesthetized with halothane. The animals underwent either a sham operation or fifteen minutes of bilateral carotid artery occlusion causing global cerebral ischemia. Capillary flow velocities were measured by frame-to-frame tracking of…

Relaxant effects of sodium nitroprusside and NONOates in goat middle cerebral artery: delayed impairment by global ischemia-reperfusion.

1999

Global cerebral ischemia and subsequent reperfusion induce early impairment of the vasodilator responses to hypercapnia and vasoactive substances. Nitric oxide (NO) is involved in the regulation of cerebral blood flow (CBF) in both health and disease. The present study was designed to assess possible changes in the cerebrovascular reactivity to NO donors induced by cerebral ischemia-reperfusion in goats. Female goats (n = 9) were subjected to 20 min global cerebral ischemia under halothane/N2O anesthesia. Sixteen additional goats were sham-operated as a control group. One week later the effects of ischemia-reperfusion on relaxations to NO donors sodium nitroprusside (SNP), diethylamine/NO (…