P2X receptor currents in smooth muscle cells contribute to nerve mediated contractions of rabbit urethral smooth muscle.

Purpose: Adenosine triphosphate is capable of relaxing and contracting urethral smooth muscle. The mechanisms responsible for the relaxing effects of adenosine triphosphate have been well studied but those involved in the contractile response are still unclear. We investigated the contributions of interstitial cells of Cajal and smooth muscle cells to nerve mediated, adenosine triphosphate dependent contractions of urethral smooth muscle.

Novel excitatory effects of adenosine triphosphate on contractile and pacemaker activity in rabbit urethral smooth muscle.

Purpose: Adenosine triphosphate is thought to be an important neurotransmitter in urethral smooth muscle but its physiological role is still unclear. We characterized the effects of adenosine triphosphate on contractile and pacemaker activity in rabbit urethral smooth muscle.

Materials And Methods: Tension recordings were made from strips of rabbit proximal urethral smooth muscle.