Table 1. Effects of paeonol, Ro 31-8220, KT-5720, Co²⁺-substituted Ca²⁺-free solution, 4-AP, TEA, and charybdotoxin on the resting membrane potential, amplitude and frequency of spontaneously generated action potentials of RP4 neurons, and effects of KT-5720, Ro 31-8220, Co²⁺-substituted Ca²⁺-free solution and TEA on paeonol-elicited action potential bursts. Values are expressed as the mean±SEM. (n being the number of neurons tested). ^bP<0.05 vs paeonol (500 μmol/L)-elicited action potential bursts. ^eP<0.05 vs the data in physiological solution (control).

Variable		n	RMP (mV)	Amplitude of action potential (mV)	Frequency of single spikes (pulse/min)	Frequency of bursts (burst/min)	Number of action potential/burst
Paeonol	Control	7	−57.7±1.8	85.1±3.3	50.1±11.2
	Paeonol (150 μmol/L)	4	−58.5±2.7	86.1±6.9	47.3±11.8
	Paeonol (500 μmol/L)	6	−55.1±1.4	80.8±5.1		8.1±1.6	5.0±0.6
	Paeonol (1.5 mmol/L)	3	−59.3±2.3	83.3±9.6		5.0±1.5	8.7±1.7b
Ro 31-8220+Paeonol	Control	5	−57.0±1.1	96.9±2.1	28.5±5.0
	Ro 31-8220 (20 μmol/L)	4	−57.7±1.2	98.8±2.2	30.0±6.7
	Ro 31-8220 (10 μmol/L)+ Paeonol (500 μmol/L)	3	−54.0±2.3	100.3±4.5		7.0±1.0	4.5±2.5
KT-5720+Paeonol	Control	3	−63.0±0.6	96.1±3.7	25.3±3.3
	KT-5720 (10 μmol/L)	3	−61.3±1.2	97.8±4.3	30.7±3.8
	KT-5720 (10 μmol/L)+ Paeonol (500 μmol/L)	3	−61.7±3.5	96.1±7.3		7.0±1.5	4.3±0.3
Paeonol in Ca2+-free	Control	6	−63.0±2.1	98.2±3.2	26.2±4.9
	Ca2+-free	3	−49.8±1.3b	65.7±3.5e	22.7±5.4
	Paeonol (500 μmol/L) in Ca2+-free	3	−58.3±1.5	73.5±5.3e		2.7±1.2e	17.3±5.3e
Paeonol+TEA	Control	3	−59.3±3.3	82.3±5.2	51.3±5.3
	TEA (5 mmol/L)	4	−57.5±1.6	86.0±3.2	29.5±3.0e
	Paeonol (150 μmol/L)+ TEA (5 mmol/L)	3	−56.3±0.7	92.7±5.6		14.7±6.7	3.7±0.9
4-AP	Control	4	−55.3±2.8	90.2±6.0	48.8±16.4
	4-AP (5 mmol/L)	4	−56.3±4.2	91.5±6.1	49.0±14.8
TEA	Control	4	−60.5±1.0	79.9±3.2	23.5±9.2
	TEA (50 mmol/L)	4	−58.0±4.0	84.4±5.6		10.5±5.5	3.1±0.7
Charybdotoxin	Control	3	−59.0±1.7	87.3±2.6	49.6±6.0
	Charybdotoxin (250 nmol/L)	3	−57.6±1.2	88.7±3.2	39.3±1.5