Page 147 - 71_04

An. R. Acad. Nac. Farm., 2005, 71: 821-833

Artículo Original

Cholinergic currents in Xenopus oocytes
transplanted with human brain membranes

LAURA TEXIDÓ, ESTEVE ROS, PIEDAD NAVARRO, JORDI
ALEU, JORDI MARSAL & CARLES SOLSONA
Laboratorio de Neurobiología Celular y Molecular.

Departamento de Patología y Terapéutica Experimental.
Facultad de Medicina. Universidad de Barcelona

ABSTRACT

Cholinergic human brain currents were recorded in Xenopus laevis oocytes
transplanted with human cerebral membranes from two different zones, the frontal
cortex and the hippocampus. The recorded currents were supported by the nicotinic
or the muscarinic acetylcholine receptor. We tested the effects of a number of
several nicotinic agonists acetylcholine, nicotine and 1,1-dimethyl-4-phenyl-
piperazinium iodide (DMPP), and the nicotinic receptor antagonists a-bungarotoxin
and d-tubocurarine on the transplanted oocytes. We detected four kinds of nicotinic
current kinetics. The differences in the amplitude and in the total electric charge
of the currents elicited by various agonists at a range of holding potentials were
not significant, except in the case of DMPP at a holding potential of -90 mV. Our
results indicate that a4ß2, a3ß4 and a7 are the main nicotinic receptors in human
brain.

Key words: Human cortex.—Neuronal nicotinic currents.—Xenopus oocytes.—
Membrane transplant.—Alzheimer.—Brain bank.

RESUMEN

Corrientes colinérgicas en oocitos de Xenopus trasplantados
con membranas de cerebro humano

Corrientes colinérgicas de cerebro humano fueron registradas en oocitos de
Xenopus laevis trasplantados con membranas de cerebro humano procedentes de

821