B A Donzanti

Learn More
An improved, HPLC with electrochemical detection method for the isocratic separation and determination of amino acids from post-mortem brain tissue and from microdialysates of awake-behaving animals is described. Optimal conditions that maximize stability, resolution, and sensitivity were determined for the pre-column derivatization of amino acids using(More)
A series of substituted phosphonate derivatives were designed and synthesized in order to study the ability of these compounds to inhibit the neuropeptidase N-acetylated alpha-linked acidic dipeptidase (NAALADase). The molecules were shown to act as inhibitors of the enzyme, with the most potent (compound 3) having a Ki of 0.275 nM. The potency of this(More)
In order to study the role of excitatory amino acids on motor function, the effects of kainic, quisqualic, and N-methyl-DL-aspartic acids on locomotor activity were determined after their direct injection into the nucleus accumbens. These three amino acids have been used in previous studies to classify receptors for excitatory amino acids in the mammalian(More)
The topographical distribution of putative neurotransmitter amino acids in both 6- and 20-month-old Fischer 344 rats was studied in eight striatal subregions. Tissue levels of glutamate, aspartate, GABA, and taurine in the 20-month-old rats were elevated in virtually all of the anterior striatal subregions examined. In addition, aspartate levels were higher(More)
The effects of synthetic omega-grammotoxin SIA (omega-GsTxSIA) and synthetic omega-Aga-IVA were tested in in vitro and in vivo neurochemical assays that are reflective of voltage-sensitive calcium channel function. Synthetic omega-GsTx SIA inhibited K(+)-evoked rat and chick synaptosomal 45Ca2+ flux, K(+)-evoked release of [3H]D-aspartate and(More)
In the lateral striatum of aged rats, dopamine D-2 receptor density is reduced and glutamate tissue content is elevated. D-2 receptor agonists have been shown to inhibit stimulated glutamate release. In the present study, microdialysis was used to investigate a potential role for D-2 receptors in the modulation of striatal glutamate efflux from 4-, 12-,(More)
A rapid microassay is described for the measurement of biogenic amines using an isocratic HPLC system with electrochemical detection. Catecholamines, indoleamines and their major metabolites were extracted with 150 microliters of perchloric acid from brain tissue punches (less than 250 micrograms) using a simple one-step sample preparation method. These(More)
The present study demonstrates that dose combinations of atropine sulfate and 2-pyridine aldoxime methylchloride (2-PAM), which do not produce any overt toxic effects on the behavior of mice or guinea pigs in a stable environment, elicit clonic-tonic convulsions and death when the animals are physically stressed by cold water swimming. Phenoxybenzamine (1-6(More)
The excitatory amino acids, N-methyl-aspartic acid, kainic acid and quisqualic acid have been shown to produce a marked increase in locomotor activity after bilateral injection into the rat nucleus accumbens. The intra-accumbens injection of magnesium inhibited the hypermotility response produced by N-methyl-aspartic acid in a dose-dependent manner.(More)
2'-beta-Fluoro-2',3'-dideoxyadenosine (F-ddA), an acid-stable, purine dideoxynucleoside with in vitro anti-HIV activity, has been selected by the NCI as a clinical trial candidate. A recent report that high, single doses of F-ddA produce cardiotoxicity in rats prompted the present investigation whose objective was to quantitate this effect and establish a(More)
  • 1