Candida albicans-induced histamine release from basophils was studied in 54 patients with bronchial asthma in comparison with the release caused by house dust and anti-IgE. The release of histamine induced by C. albicans and that induced by house dust were closely related to the serum levels of specific IgE antibodies as expressed by RAST scores. A correlation of C. albicans-induced histamine r...

Voltage-gated Kv7 channels are inhibited by agonists of Gq-protein-coupled receptors, such as histamine. Recent works have provided evidence that inhibition of vascular Kv7 channels may trigger vessel contractions. In this study, we investigated how Kv7 activity modulates the histamine-induced contractions in "healthy" and metabolic syndrome (MetS) pig right coronary arteries (CAs). We performe...

The role of endogenous histamine and H1, H2 and H3 central receptors on food intake in broiler chickenswas investigated. For this purpose, a probe was used to manipulate the concentration of endogenoushistamine by intracerebroventricular (ICV) injection of thioperamide, an H3 receptor antagonist, and R-α-methylhistamine, an H3 receptor agonist and subsequently the effects of brain histaminergic...

In the present study, infrared differential interference contrast videomicroscopy was used to examine the effect of histamine on N-methyl-D-aspartate-induced swelling in neostriatal neurons in a brain slice preparation. Histamine caused a concentration-dependent increase in swelling evoked by N-methyl-D-aspartate. By itself, histamine did not cause swelling. Electrical stimulation also caused N...

One of the common side effects of antihistamine medicines is xerostomia (dry mouth). The current consensus is that antihistamine-induced xerostomia comes from an antimuscarinic effect. Although the effect of antihistamines on salivary secretion is both obvious and significant, the cellular mechanism whereby this happens is still unclear because of the lack of knowledge of histamine signaling in...

Skin mast cells release the neutral protease chymase along with histamine during degranulation. To test the hypothesis that chymase modulates histamine-induced plasma extravasation, we measured wheal formation following intradermal injection of purified mast cell chymase and histamine into the skin of ragweed-allergic dogs. We found that chymase greatly augments histamine-induced wheal formatio...

Background Aside from their typical use to treat depression, many antidepressants are also used to treat anxiety disorders and chronic pain disorders. Moreover, it has been proved that they show anti-inflammatory effects. We believe that a part of this effect of antidepressants can arise as a consequence of histamine elimination from the site of inflammation. In mammals, histamine is mainly met...

We previously demonstrated that newly formed intracellular histamine mediates platelet aggregation in response to phorbol-12-myristate-13-acetate (PMA). We now report further investigations of the role of histamine during physiological activation of platelets by collagen. Platelets stirred with collagen produced histamine; the rise in histamine precedes the onset of aggregation. The dose respon...

Histamine potentiates activation of native and recombinant N-methyl-d-aspartate receptors (NMDARs), but its mechanisms of action and physiological functions in the brain remain controversial. Using four different models, we have further investigated the histamine-induced potentiation of various NMDAR-mediated responses. In single cultured hippocampal neurons, histamine potentiated NMDA currents...

1 Histamine and 2-methyl-histamine (H1-receptor agonist) caused dose-dependent increases in capillary permeability in albino mice, but 4-methyl-histamine (H2-receptor agonist) caused no significant increase. 2 Mepyramine (H1-receptor antagonist) blocked the histamine-induced increase in capillary permeability whereas burimamide (H2-receptor antagonist) produced no significant blockade of the hi...