Biomedical subjects

G Alemany

Publications and source records attributed to G Alemany.

6 recordsLinked to original sources

PubMed1993

Histaminergic drugs in the rat caudate nucleus: effects on learned helplessness.

The effect of pharmacological manipulation of histaminergic receptors in the caudate nucleus (CN) has been examined in rats previously submitted to inescapable electric shock to produce learned helplessness (LH). Histamine H1 agonist 2-tiazolylethyl amine (TEA) microinjection produced protective effects, preventing the activity and cognitive loss typical in LH. Injection of the H1 antagonist astemizole (AZ) produced effects symmetrical to those produced by TEA, further reducing activity and impairing cognitive functions. The histamine H2 agonist 4-methyl-histamine (4MH) produced a shift on the side preference for rotation that interfered in the learning tests and obscured the effects of this drug on LH. Injection of the H2 antagonist cymetidine (CYM) caused LH-like effects in control animals. Thus, brain histamine seems to play a relevant role in the control of motor and cognitive functions of the CN.

Animals↗

PubMedDate not supplied

Simultaneous determination of vanillylmandelic, homovanillic and 5-hydroxyindoleacetic acids in human urine by thin layer chromatography.

A TLC method for the simultaneous analysis of vanillylmandelic, homovanillic and 5-hydroxyindole-3-acetic acids in urine is described. The sample is cleaned up through a cyano minicolumn and extracted with diethyl ether. The acids are resolved by high-performance TLC, visualized by Folin Ciocalteau reagent and quantificated by densitometry at 600 nm with beta-(4-hydroxy-3-phenyl) acetic acid as the internal standard.

Chromatography, Thin Layer↗

PubMedDate not supplied

A simple thin-layer chromatographic method for the analysis of buprenorphine in urine.

A simple and sensitive (at the ng/mL level) method for buprenorphine assay in urine is described. Buprenorphine is extracted by a C18 cartridge, derivatized with dansyl chloride, resolved by a uni-dimensional, two developing mobile phase high-performance thin layer chromatography system and quantified by fluorescence densitometry at 340 nm.

Analgesics, Opioid↗

PubMedDate not supplied

Thin-layer chromatographic determination of catecholamines in rat plasma.

A TLC method for the quantitative determination of epinephrine, norepinephrine and dopamine in rat plasma is described. After deprotenization, catecholamines were adsorbed on acid-alumina and acetylated. The acetyl derivatives were extracted using a C18 minicolumn, resolved on HPTLC plates and quantitated by fluorescence densitometry at 415 nm, using isoprenaline as internal standard.

Animals↗

PubMedDate not supplied

A simple method for plasma cannabinoid separation and quantification.

A sensitive (up to nanogram level) method for resolving a cannabinoid mixture in plasma is described. Cannabinoids were extracted with a C-18 Sep Pak cartridge and derivatized with dansylchloride. Then the derivatives were resolved on thin layer HPTLC silica plates which were developed and quantified by fluorescence densitometry at 340 nm.

Cannabinoids↗

PubMedDate not supplied

Thin-layer chromatographic determination of brain catecholamines and 5-hydroxytryptamine.

A simple and sensitive (up to nanogram level) method to determine norepinephrine, serotonin and dopamine in rat brain is described. The amines are acetylated and the derivatives are resolved by thin layer chromatography (TLC) on silica high performance thin layer chromatography (HPLC) plates. Quantification is achieved by fluorescence densitometry at 415 nm excitation wavelength.

Animals↗