TY - JOUR
T1 - Caesium ions
T2 - A glycine-activated channel agonist in rat spinal cord neurones grown in cell culture
AU - Smith, S. M.
AU - McBurney, R. N.
PY - 1989
Y1 - 1989
N2 - 1. The chloride (Cl-) currents activated by caesium ions (Cs+), glycine and γ-aminobutyric acid (GABA) were compared following their application to rat neurones that had been grown in cell culture. Recordings were made using the whole-cell patch clamp technique under voltage clamp conditions. 2. In spinal cord neurones, bicuculline methiodide antagonized GABA-activated currents more effectively than Cs+- or glycine-activated currents. However, strychnine was more effective at blocking the currents activated by Cs+ or glycine than those activated by GABA. 3. Of the 3 agonists, only GABA activated currents in cells from the intermediate lobe of the rat pituitary. 4. In spinal neurones the size of the currents activated by 70 mM Cs+ was correlated to the size of the currents activated by 15 μM glycine (P < 0.005; n = 10, Spearman's rank correlation), but there was no significant correlation between the size of the currents activated by these agents and 10 μM GABA. 5. The joint application of glycine and Cs+ activated currents that were approximately twice as big as the sums of the currents activated by separate applications of the same doses. This synergism was consistent with Cs+ acting at the same receptor as glycine (7 μM glycine being equivalent to 31 ± 7 mM Cs+). 6. It was concluded that Cs+ activates the same Cl- channel as the inhibitory neurotransmitter glycine.
AB - 1. The chloride (Cl-) currents activated by caesium ions (Cs+), glycine and γ-aminobutyric acid (GABA) were compared following their application to rat neurones that had been grown in cell culture. Recordings were made using the whole-cell patch clamp technique under voltage clamp conditions. 2. In spinal cord neurones, bicuculline methiodide antagonized GABA-activated currents more effectively than Cs+- or glycine-activated currents. However, strychnine was more effective at blocking the currents activated by Cs+ or glycine than those activated by GABA. 3. Of the 3 agonists, only GABA activated currents in cells from the intermediate lobe of the rat pituitary. 4. In spinal neurones the size of the currents activated by 70 mM Cs+ was correlated to the size of the currents activated by 15 μM glycine (P < 0.005; n = 10, Spearman's rank correlation), but there was no significant correlation between the size of the currents activated by these agents and 10 μM GABA. 5. The joint application of glycine and Cs+ activated currents that were approximately twice as big as the sums of the currents activated by separate applications of the same doses. This synergism was consistent with Cs+ acting at the same receptor as glycine (7 μM glycine being equivalent to 31 ± 7 mM Cs+). 6. It was concluded that Cs+ activates the same Cl- channel as the inhibitory neurotransmitter glycine.
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U2 - 10.1111/j.1476-5381.1989.tb11905.x
DO - 10.1111/j.1476-5381.1989.tb11905.x
M3 - Article
C2 - 2472848
AN - SCOPUS:0024601247
SN - 0007-1188
VL - 96
SP - 940
EP - 948
JO - British Journal of Pharmacology
JF - British Journal of Pharmacology
IS - 4
ER -