we have measured the competitive antagonistic effect of chlorpheniramine in bronchi of 8 normal and 12 asthmatic subjects. classical pharmacological theory states that the degree of competitive antagonism depends only upon 1) antagonist concentration at the receptor, and 2) receptor affinity. delivery and affinity also influence agonist responsiveness, but measurement of bronchial antagonism al...

BACKGROUND: Brain monoamines (such as histamine and dopamine) play an important role in emotions, cognition, reward and feeding behavior. The interactions between histamine and dopamine were studied in many physiological functions but this correlation is unclear in feeding behavior of chickens. The aim of this study was to investigate the interaction of central histaminergic and dopaminergic sy...

restraint-induced stress (rs) increases histamine concentration in the brain. there is no previous report regarding the role of histamine receptors in immunomodulatory effect of rs. in the present study the role of brain histamine receptors on reduction of humoral and cellular immune function induced by rs was evaluated. for this purpose male wistar rats (200-250 g) were immunized with sheep re...

Background. Itch can be transmitted by two parallel pathways, histaminergic and nonhistaminergic. Histaminergic itch is a subgroup of mechano-insensitive C-fibers, while nonhistaminergic polymodal C-fibers. Experimental models are used to study pruritus: histamine for the antagonizing H1-receptors, BAM8-22 cowhage activating Mas-related G protein-coupled receptors protease-activated receptors, ...

Restraint-induced stress (RS) increases histamine concentration in the brain. There is no previous report regarding the role of histamine receptors in immunomodulatory effect of RS. In the present study the role of brain histamine receptors on reduction of humoral and cellular immune function induced by RS was evaluated. For this purpose male Wistar rats (200-250 g) were immunized with sheep re...

Several lines of evidence suggest that brain histamine may be involved in the central control of food intake. The effect of histamine on feeding is mediated through three kinds of receptors (H1, H2, and H3). The present study was designed to investigate the effect of intracerebroventricular injection of histamine, promethazine (H1 antagonist) and ranitidine (H2 antagonist) on food intake of fre...

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...

Several lines of evidence suggest that brain histamine may be involved in the central control of food intake. The effect of histamine on feeding is mediated through three kinds of receptors (H1, H2, and H3). The present study was designed to investigate the effect of intracerebroventricular injection of histamine, promethazine (H1 antagonist) and ranitidine (H2 antagonist) on food intake of fre...