. 2002 Mar 1;22(5):1709–1717. doi: 10.1523/JNEUROSCI.22-05-01709.2002

Table 1.

Basal and potassium-evoked release of [³H]choline and [³H]ACh in hippocampal, cortical, and striatal slices from WT mice prelabeled with [³H]choline, as determined by reverse-phase HPLC

	[³H]Choline [³H]ACh		% [³H]ACh (of total [³H])
	Disintegrations per minute/preparation		% [³H]ACh (of total [³H])
Hippocampus
Basal release^1-a	957 ± 60	1119 ± 48	52.9 ± 2.1
Release after K⁺stimulation^1-b	1092 ± 56	2516 ± 109	69.7 ± 1.1
Net increase in release after K⁺stimulation^1-c	180 ± 27	1442 ± 104	88.9 ± 1.5
Cortex
Basal release	959 ± 10	944 ± 64	49.5 ± 1.5
Release after K⁺stimulation	1166 ± 30	2285 ± 135	66.1 ± 1.6
Net increase in release after K⁺stimulation	208 ± 37	1491 ± 159	87.7 ± 2.0
Striatum
Basal release	1087 ± 140	1940 ± 182	64.3 ± 1.4
Release after K⁺stimulation	1254 ± 164	5421 ± 383	81.3 ± 1.7
Net increase in release after K⁺stimulation	167 ± 33	3481 ± 298	95.5 ± 0.7

^F1-a

Sum of disintegrations per minute of aliquots (100 μl) taken from the three fractions collected immediately before K⁺ stimulation (fractions 2–4).

^F1-b

Sum of disintegrations per minute of aliquots (100 μl) taken from the three fractions collected immediately after K⁺ stimulation (fractions 5–7).

^F1-c

([³H] outflow after K⁺ stimulation) − (basal [³H] outflow).

Tissue slices derived from WT mice (M₄ receptor WT mice) were prelabeled with [³H]choline (0.1 μm), and potassium-stimulated release of [³H]choline and [³H]ACh was determined as described in Materials and Methods. [³H]choline and [³H]ACh were separated by reverse-phase HPLC followed by liquid scintillation spectrometry (Wessler and Werhand, 1990). Data represent means ± SEM from four independent experiments (mice).