title: Post-natal change and regional variation of the response of the vas deferens of new-born rats to autonomic drugs.
abstract: The vas deferens isolated from rats of different ages (11-60 d old) was bisected to provide an epididymal and a prostatic half. The contractile responses of both halves to potassium ions, adrenergic agents (noradrenaline, isoprenaline and tyramine), cholinergic agents (acetylcholine, methacholine and tetramethylammonium), histamine and serotonin were measured. The response to 150 mM potassium, which was regarded as an approximate measure of full contractility of the preparation, increased in parallel with the organ weight. Most of the agonists could induce the full contractility in both halves until 3-4 weeks of age, but thereafter they could produce only smaller responses than the full contractility in either or both halves, resulting in a differentiation of the halves in the response to agonists. A regional variation of the post-natal development of alpha-adrenergic, muscarinic and nicotinic responses is discussed.
mesh_terms: D000818:Animals; D000831:Animals, Newborn / Q000254:growth & development; D001337:Autonomic Agents / Q000494:pharmacology*; D006632:Histamine / Q000494:pharmacology; D008297:Male; D009119:Muscle Contraction / Q000187:drug effects*; D009130:Muscle, Smooth / Q000187:drug effects; D010277:Parasympathomimetics / Q000494:pharmacology; D011188:Potassium / Q000494:pharmacology; D051381:Rats; D012701:Serotonin / Q000494:pharmacology; D013566:Sympathomimetics / Q000494:pharmacology; D014649:Vas Deferens / Q000187:drug effects / Q000254:growth & development*
chemical_list: D001337:Autonomic Agents; D010277:Parasympathomimetics; D013566:Sympathomimetics; D012701:Serotonin; D006632:Histamine; D011188:Potassium