The purpose of the study was to test the hypothesis that tachykinins mediate hyperpnea-induced induced bronchoconstriction indirectly by triggering cysteinyl leukotriene (LT) synthesis in the airways. Guinea pigs (350-600 g) were anesthetized with xylazine and pentobarbital sodium and received hyperpnea challenge (tidal volume 3.5-4.0 ml, frequency 150 breaths/min) with either humidified isocap...

Nicotine is an addictive alkaloid in cigarette smoke and is responsible for tobacco dependence. It is important to consider the blood-to-liver transport of nicotine to understand the nicotine elimination from the body because most of the nicotine is converted to inactive metabolites by cytochrome P450 localized in the endoplasmic reticulum of the hepatocytes. In this study, the blood-to-liver t...

In addition to their direct contractile effects, histamine (Hist), serotonin [5-hydroxytryptamine (5-HT)], and leukotriene (LT) D4, in low concentrations, dramatically augment electrical field stimulation (EFS)-induced smooth muscle contractions in equine airways. To determine the mechanism of their action, we studied, in trachealis strips, the effect of these mediators on both cholinergically ...

Champion, Hunter C., Trinity J. Bivalacqua, David G. Lambert, Rasheed A. Abassi, and Philip J. Kadowitz. Analysis of vasoconstrictor responses to histamine in the hindlimb vascular bed of the rabbit. Am. J. Physiol. 277 (Regulatory Integrative Comp. Physiol. 46): R1179–R1187, 1999.—Hemodynamic responses to histamine were investigated in the anesthetized rabbit. Intravenous injections of histami...

Nicotine is an addictive alkaloid in cigarette smoke and is responsible for tobacco dependence. It is important to consider the bloodto-liver transport of nicotine to understand the nicotine elimination from the body because most of the nicotine is converted to inactive metabolites by cytochrome P450 localized in the endoplasmic reticulum of the hepatocytes. In this study, the blood-to-liver tr...

BACKGROUND Mast cells have been shown to regulate intestinal ion transport in animal models and normal human colon but their physiological role in human intestinal inflammatory disorders is unknown. AIMS To examine mast cell regulation of ion transport in inflammatory bowel disease (IBD). SUBJECTS AND METHODS Small and large intestine was obtained from patients with and without IBD undergoi...

The aim of the present study was to investigate whether and by which mechanism; histamine can induce state-dependent retrieval of passive avoidance task. The pre-training or pre-test intracerebroventricular (i.c.v.) injection of histamine (20µg/mouse) impaired retrieval, when it was tested 24 h later. In the animals, which retrieval was impaired due to histamine pre-training administration, pre...

The aim of the present study was to investigate whether and by which mechanism; histamine can induce state-dependent retrieval of passive avoidance task. The pre-training or pre-test intracerebroventricular (i.c.v.) injection of histamine (20µg/mouse) impaired retrieval, when it was tested 24 h later. In the animals, which retrieval was impaired due to histamine pre-training administration, pre...

Previous reports demonstrated that the expression of thrombomodulin (TM) in endothelial cells was modulated by various agents. Although TM was down-regulated by endotoxin or cytokines, up-regulation of TM was accomplished when endothelial cells were stimulated with unphysiologically high concentrations of cyclic AMP derivatives or tumour-promoting phorbol esters. We investigated the expression ...