The mechanisms of relaxation of adrenomedullin were investigated in isolated mesenteric artery from pregnant rats. Adrenomedullin (1 nM-0.3 microM) produced concentration-dependent relaxation of endothelium-denuded mesenteric artery rings precontracted with norepinephrine at a concentration required to produce 70% of maximal response (ED70). The concentration-response curve of adrenomedullin wa...

Farrukh, Imad S., Wei Peng, Urszula Orlinska, and John R. Hoidal. Effect of dehydroepiandrosterone on hypoxic pulmonary vasoconstriction: a Ca21-activated K1channel opener. Am. J. Physiol. 274 (Lung Cell. Mol. Physiol. 18): L186–L195, 1998.—In the present study, we investigated the effects of the naturally occurring hormone dehydroepiandrosterone (DHEA) on hypoxic pulmonary vasoconstriction (HP...

We use ultrafast optical spectroscopy to study the nonequilibrium quasiparticle relaxation dynamics of iron-based superconductor KCa$_2$Fe$_4$As$_4$F$_2$ with $T_c=33.5$ K. Our results reveal a possible pseudogap ($\Delta_{PG}$ = 2.4 $\pm$ 0.1 meV) below $T^*\approx 50$ K but prior opening superconducting gap ($\Delta_{SC}$(0) $\approx$ 4.3 meV). Measurements under high pump fluence real two di...

Malinina E, Druzin M, Johansson S. Differential control of spontaneous and evoked GABA release by presynaptic L-type Ca channels in the rat medial preoptic nucleus. J Neurophysiol 104: 200–209, 2010. First published May 12, 2010; doi:10.1152/jn.00570.2009. To clarify the role of presynaptic L-type Ca channels in GABA-mediated transmission in the medial preoptic nucleus (MPN), spontaneous, minia...

In the present study, we investigated the effects of the naturally occurring hormone dehydroepiandrosterone (DHEA) on hypoxic pulmonary vasoconstriction (HPVC) in isolated ferret lungs and on K+ currents in isolated and cultured ferret pulmonary arterial smooth muscle cells (FPSMCs). Severe alveolar hypoxia (3% O2-5% CO2-92% N2) caused an initial increase in pulmonary arterial pressure (Ppa) th...

Ca release through ryanodine receptors (RyRs) in the sarcoplasmic reticulum is a key element of excitation-contraction coupling in muscle. In arterial smooth muscle, Ca release through RyRs activates Ca-sensitive K (KCa) channels to oppose vasoconstriction. Local Ca 21 transients (“Ca sparks”), apparently caused by opening of clustered RyRs, have been observed in smooth and striated muscle. We ...

Various types of neurons exhibit subthreshold resonance oscillation (preferred frequency response) to fluctuating sinusoidal input currents. This phenomenon is well known to influence the synaptic plasticity and frequency of neural network oscillation. This study evaluates the resonant properties of pacemaker pyloric dilator (PD) neurons in the central pattern generator network through mathemat...

Ischemia and reperfusion (IR) injury constitutes one of the major causes of cardiovascular morbidity and mortality. The discovery of new therapies to block/mediate the effects of IR is therefore an important goal in the biomedical sciences. Dysfunction associated with IR involves modification of calcium-activated potassium channels (KCa) through different mechanisms, which are still under study...