Meldrum L A, Burnstock G
Comp Biochem Physiol C Comp Pharmacol Toxicol. 1985;81(2):307-9. doi: 10.1016/0742-8413(85)90011-8.
ATP and substance P were examined as possible mediators of non-adrenergic, non-cholinergic excitatory transmission in chicken rectum. ATP and the non-degradable ATP analogue, alpha, beta-methylene ATP, mimicked the response to nerve stimulation. Substance P either produced a maintained contraction after a long latency or was inactive. After desensitization of the P2-purinoceptor by alpha, beta-methylene ATP, the responses to ATP and nerve stimulation were abolished, while the response to carbachol was little affected. It is concluded that ATP may be the transmitter in non-adrenergic, non-cholinergic excitatory nerves supplying the chicken rectum.