Table 6.

Effects of desensitization or blockade of P2X₁and/or P2X₃ receptors with α,β-meATP or TNP-ATP, respectively, on contractions evoked by EFS (1 ms, 8 and 16 Hz, 20 s trains) and ATP (1 mM) on basal tone of pig bladder neck strips pretreated with phentolamine (0.1 µM) and N^G-nitro-L-arginine (100 µM) to block α-adrenoceptors and nitric oxide synthase respectively

	n	EFS (Hz)		ATP (mM)
		8	16	1
Control	9	18 ± 5	24 ± 4	5 ± 2
α,β-meATP (10 µM)	9	18 ± 5	21 ± 4	4 ± 2
Control	9	12 ± 3	19 ± 4	4 ± 1
TNP-ATP (30 µM)	9	12 ± 3	20 ± 4	4 ± 1

Results are expressed as percentage of the potassium-rich physiological saline solution (124 mM)-induced tone and represent the mean ± SEM of n preparations.

α,β-meATP, α,β-methylene adenosine 5′-triphosphate; ATP, adenosine 5′-triphosphate; EFS, electrical field stimulation; TNP-ATP, 2′, 3′-O-(2,4,6-trinitrophenyl)adenosine-5′-triphosphate tetratriethylammonium.