SUPPLEMENTARY STUDIES ON THE SITES OF ACTION OF PILOCARPINE

• Published in: Japanese journal of pharmacology Vol. 7; no. 2; pp. 94 - 103
• Main Authors: SHIMAMOTO, KIRO, INOUE, KUNIO
• Format: Journal Article
• Language: English
• Published: The Japanese Pharmacological Society 1958
• ISSN: 0021-5198; 1347-3506
• DOI: 10.1254/jjp.7.94

Although it is generally accepted that pilocarpine affects the postganglionic cholinergic receptors and reveals a strong muscarinic action selectively, evidence has been cited to conclude that the drug affects other sites of the effector organs. Large doses of the drug do not induce a rise of blood pressure in an atropinized animal. But Dale and Laidlaw (1), Marrazi (2) and Ambache (3) concluded that pilocarpine stimulated the superior cervical ganglion in the cat, based on the experimental results that the drug potentiated the contraction of the nictitating membrane and the postganglionic electrical potential in response to preganglionic sympathetic stimulation. Feldberg et al. (4) proved that pilocarpine induced a discharge of adrenaline from the adrenals. The authors all agreed that the ganglion stimulating action of pilocarpine was abolished after the administration of atropine in large doses. The evidence that pilocarpine induced a strong pressor action on the blood pressure after the administration of such ganglion blocking agents as nicotine (5), d-tubocurarine and tetraethylammonium (6), hexamethonium, laurifoline and menisperine (7) raises the question regarding other sites of the action of pilocarpine. Another question to be investigated is raised by the evidence that in the course of recovery from the augmenting effect of pilocarpine the salivary response of the submaxillary gland to stimulation of the chorda tympani was depressed (8). Lastly, there is the problem of the innervation and the response of the sweat glands to nerve stimulation. The sweat glands are innervated by the sympathetic postganglionic fibers, but they respond not to adrenergic but to cholinergic drugs. These former three questions were studied in the present investigation to clarify the mechanism and the site of the action of pilocarpine.