Postnatal development of purinoceptors in rat visceral smooth muscle preparations.

1. Adenosine and ATP have well-established functions as neuromodulator and neurotransmitter, respectively, in smooth muscle preparations, and purinergic control may be an early form of autonomic control in both evolution and ontogenesis. 2. This review describes the postnatal development of responses mediated by the various receptors for adenosine and for nucleotides in the rat duodenum, colon, urinary bladder and vas deferens and considers the implications that this development may have for the importance of purinergic control in neonates and adults.