Cardiac pacemaking, at rest and during the sympathetic fight-or-flight response, depends on cAMP (3',5'-cyclic adenosine monophosphate) signaling in sinoatrial node myocytes (SAMs). The cardiac "funny current" (If) is among the cAMP-sensitive effectors that drive pacemaking in SAMs. If is produced by hyperpolarization-activated, cyclic nucleotide-sensitive (HCN) channels. Voltage-dependent gati...

BACKGROUND A number of studies have shown that ethanol (EtOH) activates dopamine neurocircuitries and is self-administered into the ventral tegmental area (VTA) of the rat brain. In vitro and in silico studies have showed that hyperpolarization-activated cyclic nucleotide-gated (HCN) ionic channels on VTA dopamine neurons may constitute a molecular target of EtOH; however, there is no in vivo e...

The hyperpolarization-activated cation current (I(h)), mediated by HCN channels, contributes to intrinsic neuronal properties, synaptic integration and network rhythmicity. Recent studies have implicated HCN channels in neuropathological conditions including epilepsy. While native HCN channels have been studied at the macroscopic level, the biophysical characteristics of individual neuronal HCN...

Hydrogen sulfide (H2S), an endogenously produced small molecule, protects animals from various stresses. Recent studies demonstrate that animals exposed to H2S are long lived, resistant to hypoxia, and resistant to ischemia-reperfusion injury. We performed a forward genetic screen to gain insights into the molecular mechanisms Caenorhabditis elegans uses to appropriately respond to H2S. At leas...

BACKGROUND The pacemaker current I(f) contributes to spontaneous diastolic depolarization of cardiac autonomic cells. In heterologous expression, HCN channels exhibit a hyperpolarization-activated inward current similar to I(f). However, the links between HCN genes and native I(f) are largely inferential, and it remains unknown whether I(f) is essential for cardiac pacing. METHODS AND RESULTS...

This paper reports the results of our use of Cavity Ring Down Spectroscopy to extend the study of highly excited vibrational states in HCN. We extend our previous study of the HCN isotopomer, reporting on some weaker bands between 17 500 and 19 500 cm. We also report spectra of overtone and combination bands with six, seven, and eight quanta of stretching vibration in the isotopomers HCN and HC...

A versatile, continuous wave, optical parametric oscillator is used in combination with photoacoustic spectroscopy for long-term trace gas experiments of volatile compounds emitted by biological samples. The optical parametric oscillator-based spectrometer (wavelength near 3 μm, 8-MHz linewidth, output power ∼1 W) is successfully tested for the detection of hydrogen cyanide (HCN) emission from ...

The architecture and operation of a trace hydrogen cyanide (HCN) gas sensor based on quartz-enhanced photo-acoustic spectroscopy and using a λ = 1.53 µm telecommu-nication diode laser are described. The influence of humidity content in the analyzed gas on the sensor performance is investigated. A kinetic model describing the vibrational to translational (V–T) energy transfer following the laser...

We have observed the 3-2 transitions of DCN and HC 15 N in a number of hot molecular cores previously surveyed by us with the interesting result that the DCN/HCN ratio is low, a few times 10 ?3 , in the hot cores. The abundance ratio of DCN/HCN is derived bothòn-core' andòo-core' and, in general is larger at thèoo-core' positions. Comparision with chemical models of these sources indicates that...

We present a sensitive 3 upper limit of 1.1% for the HNC/HCN abundance ratio in comet 73P/SchwassmannWachmann (fragment B), obtained on 2006May 10Y11, using Caltech Submillimeter Observatory (CSO). This limit is a factor of 7 lower than the values measured previously in moderately active comets at 1 AU from the Sun. Comet 73P/Schwassmann-Wachmann was depleted in most volatile species, except of...