the exact role of the epithelial lining of the trachea in modulating the bronchial tone is controversial. the present study was an attempt to verify the role of both prostaglandins and mast cells in the acute phase of acid inspiration in rat. four groups (n = 6) of n. mari rats were employed. the first group was used as placebo control, and normal saline was injected. to the second group hydroc...

the effect of repetitive electrical field stimulation and the response of the guinea-pig and rat ileal longitudinal muscle to single pulse stimulations was examined. single pulse field stimulation produced twitch contraction which was inhibited by repetitive field stimulation (10 hz, 40v, 0.5 msec for 5 m). this inhibition was largely, though never completely, reversed by naloxone. contractions...

ketotifen is a benzocycloheptathiophene with a range of pharmacological activities. the present study was carried out to evaluate the action of ketotifen on isolated rat bladder contractions induced by kci and acetylcholine, compared with the effects of other drugs. ketotifen (5 µm) reduced the response to acetylcholine on rat isolated bladder without altering the maximum response and shifted t...

The effect of repetitive electrical field stimulation and the response of the guinea-pig and rat ileal longitudinal muscle to single pulse stimulations was examined. Single pulse field stimulation produced twitch contraction which was inhibited by repetitive field stimulation (10 Hz, 40V, 0.5 msec for 5 m). This inhibition was largely, though never completely, reversed by naloxone. Contrac...

Background: The authors investigated whether acetylcholine-induced contraction in pulmonary venous smooth muscle (PVSM) is associated with the activation of specific protein kinase C (PKC) isoforms. Methods: Isolated canine pulmonary venous rings without endothelium were suspended in modified Krebs-Ringer’s buffer for measurement of isometric tension. The effects of nonspecific PKC inhibition (...

Ketotifen is a benzocycloheptathiophene with a range of pharmacological activities. The present study was carried out to evaluate the action of ketotifen on isolated rat bladder contractions induced by KCI and acetylcholine, compared with the effects of other drugs. Ketotifen (5 µM) reduced the response to acetylcholine on rat isolated bladder without altering the maximum response and shift...

The goal of this study was to determine whether acetylcholine evokes endothelium-dependent contraction in mouse arteries and to define the mechanisms involved in regulating this response. Arterial rings isolated from wild-type (WT) and endothelial nitric oxide (NO) synthase knockout (eNOS(-/-)) mice were suspended for isometric tension recording. In abdominal aorta from WT mice contracted with ...

BACKGROUND The authors investigated the extent and cellular mechanisms by which the intravenous anesthetic ketamine alters acetylcholine-induced contraction in pulmonary veins (PVs). They tested the hypothesis that ketamine inhibits acetylcholine contraction in PVs. METHODS Canine PV rings with endothelium (E+) and without endothelium (E-) were isolated for measurement of isometric tension. T...

OBJECTIVE Many biological studies have been done to determine the activity of medicinal plants on gastrointestinal function. Since acetylcholine is the major transmitter involved in the gastrointestinal motility and there are some evidences regarding the cholinergic modulatory effect of hops extract, in the present study spasmolytic and antispasmodic action of hops (Humulus lupulus) on acetylch...