Adenosine 5′-triphosphate and its relationship with other mediators that activate pelvic nerve afferent neurons in the rat colorectum

• DOI: 10.1007/s11302-005-5305-2
• Publication Date: 2006-08-25T15:00:57Z
• Authors: Gregory Wynn; Geoffrey Burnstock
• Keywords: Adenosine triphosphate; Free nerve ending

Evidence of a role for purinergic signalling in visceral afferents involving P2X(2), P2X(3) and P2Y(1) receptors exists, which appears to be important during inflammation. This study aimed evaluate the degree interaction between adenosine 5'-triphosphate (ATP) other mediators that activate sensory nerves colorectum. Recordings from pelvic nerve were made application agents in-vitro colorectal preparation. Analysis allowed calculation single unit activity. When applied individually, bradykinin (78%) 5-hydoxytryptamine (77%) activated greatest number neurons, followed by substance P, protons, ATP capsaicin. Prostaglandin E(2) stimulated least (54%) had longer latency. Seventy-seven percent all units studied either responded both capsaicin or neither, giving activity correlation. Five seven no agent alone. 5-hydroxytryptamine, when co-applied with ATP, increased greater than sum individual responses. It is concluded activates acts synergistically 5-hydroxytryptamine. The pattern neuronal activation suggests are polymodal but receptor expression on their terminals variable.