The administration of nicotinamide to the mouse results in an Sto lo-fold increase in the diphosphopyridinc nucleotide content of the liver as previously reported by Kaplan et al. (l-3). Corresponding doses of nicotinic acid are far less effective than nicotinamide in eliciting a net synthesis of DPN (3). This is in contrast to the nicotinic acid specificity which has been observed for DPN synt...

BACKGROUND The major fuel for exercising muscle at low exercise intensities is fat. OBJECTIVE To investigate the role of fat metabolism in McArdle disease (also known as glycogen storage disease type V), an inborn error of muscle glycogenolysis, by manipulating free fatty acid availability for oxidation during exercise. DESIGN Randomized, placebo-controlled, crossover trial. SETTING Hospi...

The second transmembrane domain (TMD2) of the Cys-loop family of ligand-gated ion channels forms the channel pore. The functional role of the amino acid residues contributing to the channel pore in neuronal nicotinic a3 receptors is not well understood. We characterized the contribution of TMD2 position V70 to channel gating in neuronal nicotinic a3 receptors. Site-directed mutagenesis was used...

A cDNA which encodes a protein tyrosine phosphatase with two src homology 2 (SH2) domains was isolated from a rat brain cDNA library. This phosphatase appears to be a rat homologue of PTP1D based on its amino acid sequence. The gene is expressed in a variety of tissues, and its mRNA is enriched in the brain, skeletal muscle, and lung. An RNA splice variant (PTP1Di) was also isolated which has f...

Nicotinic acid (niacin) has long been used as an antidyslipidemic drug. Its special profile of actions, especially the rise in HDL-cholesterol levels induced by nicotinic acid, is unique among the currently available pharmacological tools to treat lipid disorders. Recently, a G-protein-coupled receptor, termed GPR109A (HM74A in humans, PUMA-G in mice), was described and shown to mediate the nic...

The nicotinic cholinergic antagonist, dihydro-beta-erythroidine, binds to two sites in rat cortical membranes with dissociation constants of 4 and 22 nM and respective apparent Bmax values of 52 and 164 fmol/mg of protein. Binding to the higher affinity site, defined by the use of 2 nM [3H]dihydro-beta-erythroidine, was saturable, reversible, and susceptible to protein denaturation. Binding was...

In addition to their ionotropic role, neuronal nicotinic acetylcholine receptors (nAChRs) can influence second messenger levels, transmitter release and gene transcription. In this study, we show that nAChRs in an insect CNS control cGMP levels by coupling to NO production. In conditions that inhibit spiking, nicotine induced cGMP synthesis. This increase in cGMP was blocked by nicotinic antago...

1. Nicotinic effects on glycine release were investigated in slices of lumbar spinal cord using conventional whole-cell recordings. In most of the substantia gelatinosa (SG) neurons tested, nicotine increased the frequency of the glycinergic spontaneous miniature inhibitory postsynaptic currents (mIPSCs). In a smaller proportion, nicotine evoked not only this same presynaptic response but also ...

The inability of vitamin Be-deficient rats and mice to convert dietary tryptophan to nicotinic acid and its metabolites has been observed by several workers (l-4). Further, when vitamin Be supplements were given to rats previously deficient in the vitamin, the animals usually recovered the ability to transform tryptophan into nicotinic acid metabolites, although the response was apparently infl...

Clinical reports suggest a positive association between fat consumption and the incidence of hyperactivity, impulsivity and cognitive abnormalities. To investigate possible mechanisms underlying these disturbances under short-term conditions, we examined in Sprague-Dawley rats the influence of 7-day consumption of a high-fat diet (HFD) compared to chow on anxiety, novelty-seeking and explorator...