Phencyclidine-induced depressions of cerebellar purkinje neurons

Local administration of phencyclidine (PCP) by pressure ejection elicited a dose-dependent slowing of the spontaneous discharge of cerebellar Purkinje neurons. Ketamine also depressed firing and was much less potent than PCP. Effects of both PCP and ketamine were antagonized by local or parenteral administration of antipsychotic drugs. The similarities between the electrophysiological and behavioral actions of phencyclidine suggest that alterations in neuronal discharge may underlie its psychotomimetic properties.     

Determination of the relative and absolute stereochemistry of a potent and α1A-selective adrenoceptor antagonist

The binding affinities and selectivities of antagonists Figure 1 and Scheme 2 for the α_1A-adrenoceptor are dependent on the stereochemical orientation of the groups at the C-4 and C-5 positions of the oxazolidinone ring. The unambiguous assignment of the relative and absolute configurations of the diastereomers of SNAP 7915 (Figure 1 and Scheme 2) is reported.     

Interference by lipids in the determination of protein using bicinchoninic acid

Bicinchoninic acid forms the basis of an analytical method for the determination of protein. The reagent produces a purple complex with cuprous ion (Cu+) in an alkaline environment and is the basis for the monitoring of cuprous ions produced in the reactions of proteins with alkaline Cu2+. This method of protein determination was reported to have greater tolerance to many commonly encountered interfering compounds, when compared to the Lowry technique. However, we have found the bicinchoninic acid technique to produce erroneously high values for protein when common membrane phospholipids were included in the assay. Phospholipids in the presence of bicinchoninic acid produced an absorbance peak similar to that produced by protein. This absorbance was linear with concentration, however, the slope varied for individual phospholipids. The combined absorption of phospholipid and protein was not strictly additive. The results indicate that the presence of appreciable quantities of lipid in samples can cause significant error in the analysis of protein by the bicinchoninic acid procedure.