in the present study, the effect of apamin (potassium channel blocker) on tolerance to cocaine-induced locomotor activity in mice has been investigated. locomotor activity was measured by locomotor activity meter, animax, type s (lkb, farrad). intraperitoneal (ip) injection of different doses of cocaine (2.5, 5, 10 and 15 mg/kg) produced dose-dependent locomotor activity in mice.animals were tr...

Undifferentiated PC12 cell produce high levels of apamin receptors (measured with 125I-apamin) after 7 days in culture. These levels are at least 50 times higher than those found in other cellular types which are also known to have apamin receptors and apamin-sensitive Ca2+-activated K+ channels in their membranes. Treatment of undifferentiated PC12 cells with nerve growth factor maintains thes...

Environmental noise exposure may increase sympathetic tone and lead to atrial fibrillation (AF) mortality. The small conductance Ca2+- activated K+ (SK) channels play important roles in the repolarization of atria. regulation SK might be involved modulating cardiac electrophysiology via autonomic nervous system (ANS). Apamin blocks specifically is used for evaluating related exposure. To determ...

UNLABELLED Apamin is a potent blocker of calcium-activated small conductance potassium (SK) channels in neurons, liver, skeletal muscle and ileum smooth muscle, but not in cardiac muscle. Cardiac muscle is devoid of SK channels; however, in isolated, single ventricular myocytes apamin is an extremely potent blocker of the L-type calcium current, and the anti-arrhythmic drug quinidine reverses a...

Apamin, a peptide component of bee venom (BV), has anti-inflammatory properties. However, the molecular mechanisms by which apamin prevents atherosclerosis are not fully understood. We examined the effect of apamin on atherosclerotic mice. Atherosclerotic mice received intraperitoneal (ip) injections of lipopolysaccharide (LPS, 2 mg/kg) to induce atherosclerotic change and were fed an atherogen...

BACKGROUND Apamin is commonly used as a small-conductance Ca2+-activated K+ (SK) current inhibitor. However, the specificity of apamin in cardiac tissues remains unclear. OBJECTIVE To test the hypothesis that apamin does not inhibit any major cardiac ion currents. METHODS We studied human embryonic kidney (HEK) 293 cells that expressed human voltage-gated Na+, K+ and Ca2+ currents and isola...

Melittin and apamin are the main components of bee venom and they have been known to have anti-inflammatory and anti-fibrotic properties. The aim of this study was to evaluate the effect of melittin and apamin on airborne fungi-induced chemical mediator and extracellular matrix (ECM) production in nasal fibroblasts. Primary nasal fibroblasts were isolated from nasal polyps, which were collected...

Apamin blocks SK channels responsible for long-lasting hyperpolarization following the action potential. Using an olfactory associative task, the effect of an intracerebroventricular 0.3 ng apamin injection was tested on learning and memory. Apamin did not modify the learning of the procedure side of the task or the learning of the odor-reward association. To test reference memory specifically,...

Apis mellifera venom is one of the best characterized venoms among Hymenoptera, yet relatively little is known about venom belonging to other species in the genus Apis. Melittin, one of the most important bioactive peptides, has been isolated and characterized in A. mellifera, Apis cerana, Apis dorsata and Apis florea, while apamin has been only characterized in A. mellifera and A. cerana. At p...