The effect of @entity284 addiction on cyclic nucleotide levels in regions of XXXX brain.

@entity268 @entity8613 @entity8262 @entity1919 @entity284 @entity35
Studies of tissue culture cells and tissue slices have implicated the nucleotides, @entity1919 and @entity8262 , in the mechanism of action of opiates. However, there are little in vivo data to corroborate this hypothesis. We addicted @entity35 to the synthetic opiate, @entity284 , by providing the drug in their drinking water (dosage 2.1 mg./kg./day). The two @entity8613 were measured in four brain areas which contain a high concentration of opiate receptors: amygdala, neostriatum, periventricular grey, and thalamus. Data were obtained after acute exposure of the drug (1 day), tolerance (35 days), withdrawal (35 days on drug then 1 day off drug), and readjustment (35 days on drug then 21 days off drug). @entity8262 levels were low (0.03 pmol./mg. tissue) in the four regions and did not differ significantly during the experiment. @entity1919 levels were higher (1-3 pmol./mg.) and fluctuated consistently in the four regions. After acute @entity284 treatment, there was a reduction in @entity1919 , which continued at lower levels after tolerance. One day of withdrawal led to increased @entity268 , which rose to near control levels. After readjustment, the levels were reduced. These data indicate an involvement of @entity1919 in the addiction and withdrawal processes in the intact animal.
