Effects of some autonomic drugs on the isolated human minor calyx

The effects of some autonomic drugs on the isolated human minor calyceal strips were investigated quantitatively. Norepinephrine, epinephrine and phenylephrine dose dependently increased the basal tone and the frequency of spontaneous contractions and decreased their amplitudes, which were depressed by phentolamine. Acetylcholine at high doses increased the basal tone and decreased the amplitude, which were depressed by atropine without changing the frequency. These findings indicate the existence of alpha-adrenoceptors and muscarinic receptors in the human minor calyceal smooth muscles.