Relationship between soil lead and airborne lead concentrations at Springfield, Missouri, USA.

This study tests whether lead deposited to soil from automobiles during past years in a medium-sized US city (population 150,000) may present a current health risk. It examines the relationship between current soil lead concentrations at nine locations within the city of Springfield, Missouri, and airborne lead levels measured at the same locations during years (1975-1981) when lead emissions from automobiles were much greater than at present. A strong, significant correlation is found between soil and airborne lead levels at eight of the sites (r = 0.

Are GAD65 and GAD67 associated with specific pools of GABA in brain?

Brain contains at least two pools of gamma-aminobutyric acid (GABA), the transmitter pool and the so-called metabolic pool. To a large extent these pools may reflect the presence of GABA in different intracellular compartments, as immunocytochemical studies show that GABA is not localized mainly in terminals but is distributed throughout neurons. An interesting issue is the extent to which the two major forms of glutamate decarboxylase (GAD65 and GAD67) are specialized to synthesize GABA for these pools.

Modulation of morphine antinociception by the brain-penetrating H2 antagonist zolantidine: detailed characterization in five nociceptive test systems.

Because histamine (HA) in the CNS may be a mediator of antinociception, a detailed investigation of the effects of the brain-penetrating H2 antagonist zolantidine (ZOL) was performed on five nociceptive tests in the presence and absence of morphine (MOR) in rats. ZOL inhibited MOR antinociception on the tail flick test, although a diurnal difference (inhibition in the dark cycle >> light cycle) was found. Similar results were found with the hot plate test, although details of the test procedure were significant.

Histamine-mediated neuronal death in a rat model of Wernicke's encephalopathy.

Three experiments were conducted to examine the role of histamine in neuronal degeneration in a rat model of Wernicke's encephalopathy induced by an acute bout of pyrithiamine-induced thiamine deficiency (PTD). In the first experiment, histamine levels in medial thalamus of freely moving PTD rats measured by microdialysis were increased (180% of controls) at a prelesion stage of thiamine deficiency (treatment day 12) and further elevated 48 hr later (380%) in the same animals when necrosis was evident. Histamine levels in dialysates of the hippocampus collected simultaneously from the same animals were unchanged at either stage of thiamine deficiency.

Characterization of basal and morphine-induced histamine release in the rat periaqueductal gray.

Previous studies have shown that antinociceptive doses of systemic morphine increase extracellular histamine (HA) levels in the rat periaqueductal gray (PAG), although the cellular origin of basal and morphine-induced HA release in the PAG is unknown. Treatment with alpha-fluoromethylhistidine (FMH; 100 mg/kg, i.p.