To determine whether the -dendrotoxin ( -DTX)-sensitive current [D current, slow inactivating transient current (ID)] contributes to the modification of neuronal function in small-diameter adult rat trigeminal ganglion (TG) neurons insensitive to 1 M tetrodotoxin (TTX), we performed two different types of experiments. In the voltage-clamp mode, two distinct K current components, a fast inactiva...

Opioid analgesia is influenced by many factors, including the 1 receptor system. Current studies show the importance of supraspinal mechanisms in these 1 actions. Given supraspinally, the 1 receptor agonist ( )pentazocine diminished systemic , , 1, and 3 opioid analgesia in CD-1 mice. There was a trend for the drugs to be more sensitive to the fixed dose of ( )pentazocine, although the differen...

The effect of central and peripheral administration of a nitric oxide synthase inhibitor, N-nitro-L-arginine methyl ester (L-NAME), on the hypothermia induced by the selective -opioid receptor agonist trans-( )3,4-dichloro-N-methyl-N-(2-[1-pyrrolidinyl]-cyclohexyl)-benzeneacetamide methane sulfate (U50,488H) was studied in male Sprague-Dawley rats. In the first series of experiments, we examine...

Apoptosis is programed cell death characterized by certain cellular changes and regulated by various gene products including Bcl-2 and caspase-1. The marijuana cannabinoid, Dtetrahydrocannabinol (THC), has been reported to suppress in culture the proliferation of splenocytes and increase the release of IL-1 from macrophages; however, the mechanisms of these effects remain unclear. Because canna...

Previous studies have shown that chronic ethanol influences the density of central m-opioid receptors and serotonin1A (5-hydroxytryptamine1A) receptors. To determine whether the functional coupling of these two receptors to G proteins in the rat brain, particularly in mesocorticolimbic regions, is affected by ethanol, receptor-mediated [S]guanosine-59O-(3-thio)-triphosphate ([S]GTPgS) binding s...

Long-term administration of cyclosporine (CsA) has been shown to cause hypercholesteremia, hypertriglyceridemia, and elevations of plasma low-density and very low-density lipoprotein (LDL and VLDL) levels in humans. This study was undertaken to explore the effects of CsA on expressions of the key lipid regulatory enzymes and receptors. Thus, hepatic expressions of cholesterol 7a-hydroxylase (th...

Metabotropic glutamate subtype-5 receptors (mGluR5) are implicated in several neuropsychiatric disorders. Positron emission tomography (PET) with a suitable radioligand may enable monitoring of regional brain mGluR5 density before and during treatments. We have developed a new radioligand, 3-fluoro-5-(2-(2[F](fluoromethyl)thiazol-4-yl)ethynyl)benzonitrile ([F]SP203), for imaging brain mGluR5 in...

We examined the cardioprotective profile of the new A3 adenosine receptor (AR) agonist CP-532,903 [N-(2,5-dichlorobenzyl)-3 -aminoadenosine-5 -N-methylcarboxamide] in an in vivo mouse model of infarction and an isolated heart model of global ischemia/reperfusion injury. In radioligand binding and cAMP accumulation assays using human embryonic kidney 293 cells expressing recombinant mouse ARs, C...

Sensory C-fibers have been implicated in the control of vascular tone and are believed to be predominantly arteriolar in the microvasculature. There have been no direct investigations into the effects of C-fiber activation in venous microvessels. Therefore, we have investigated the effects of neuropeptides and activation of sensory C-fibers in rat small mesenteric veins. Small secondor third-or...

The in vivo characteristics of [C]befloxatone were assessed in myocardium of rats and monkeys. A complete multicompartmental model was developed to quantify monkey cardiac monoamine oxidase A (MAO-A) binding sites using positron emission tomography (PET) and was applied to assess the acute effects of inhalation of tobacco smoke. Unknown compounds contained in tobacco smoke inhibit brain MAO. In...