Abstract
1 Compared with the response of preparations incubated in solutions without clonidine, a three to four fold increase in the magnitude of the contracture of the longitudinal muscle to challenge with phentolamine (1.0 μm) was induced by incubating the guinea-pig isolated ileum at 22°C for 24 h with clonidine (1.0 μm) in Krebs solution containing hexamethonium (70 μm). Incubation of the ileum with clondine (1.0 μm) for 0.5 h at 37°C did not increase responsiveness to phentolamine.
2 The increase in responsiveness to phentolamine was directly related to the clonidine concentration in the incubation fluid over the range 0.01 to 1.0 μm.
3 The magnitude of the contracture to phentolamine of ilea incubated with clonidine (1.0 μm) (withdrawal contracture) was directly related to the challenge dose of phentolamine over the range 0.3 to 1.0 μm.
4 Yohimbine (1.0 μm) or piperoxane (1.0 μm) elicited a response comparable to that elicited by phentolamine but propranolol (1.0 μm) was inactive.
5 Addition of phentolamine (1.0 μm) to clonidine (1.0 μm) in the incubation fluid abolished the increased response of the preparation to subsequent challenge with phentolamine.
6 Addition of hyoscine (0.5 μm) immediately after challenge with phentolamine restored the tension of the withdrawal contracture to its resting level.
7 Tetrodotoxin (3.0 μm) given before challenge, prevented phentolamine from eliciting a withdrawal contracture.
8 Ileal segments incubated with clonidine (1.0 μm) were unresponsive to challenge with naloxone (100 nm); and segments incubated with normorphine (1.0 μm) were unresponsive to phentolamine (1.0 μm), although responsive to naloxone.
9 Normorphine (1.0 μm) restored to resting level the tension of the clonidine withdrawal contracture; and clonidine (0.1 μm) restored to resting level the tension of the contracture to naloxone in ileal segments incubated with normorphine.
10 These experiments indicate that incubation with clonidine induces, in the final cholinergic motor neurones of the myenteric plexus of the isolated ileum, a dependence the withdrawal from which is expressed as a contracture in response to α-adrenoceptor antagonists.
11 Although opiate receptors are not involved in clonidine dependence nor α-adrenoceptors in opiate dependence, the findings that normorphine suppresses the clonidine withdrawal-contracture and that clonidine suppresses the contracture of opiate-dependent ileum to naloxone, suggest that the withdrawal effect studied in both clonidine and normorphine dependence in this preparation is mediated by release of acetylcholine from the final motor neurone.
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Selected References
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- Aghajanian G. K. Tolerance of locus coeruleus neurones to morphine and suppression of withdrawal response by clonidine. Nature. 1978 Nov 9;276(5684):186–188. doi: 10.1038/276186a0. [DOI] [PubMed] [Google Scholar]
- Collier H. O. Cellular site of opiate dependence. Nature. 1980 Feb 14;283(5748):625–629. doi: 10.1038/283625a0. [DOI] [PubMed] [Google Scholar]
- Crawley J. N., Laverty R., Roth R. H. Clonidine reversal of increased norepinephrine metabolite levels during morphine withdrawal. Eur J Pharmacol. 1979 Aug 1;57(2-3):247–250. doi: 10.1016/0014-2999(79)90372-8. [DOI] [PubMed] [Google Scholar]
- Deck R., Oberdorf A., Kroneberg G. Die Wirkung von 2-(2,b-Dichlorphenylamino)-2-imidazolin-Hydrochlorid (Clonidin) auf die Kontraktion und die Acetylcholin-Freisetzung am isolierten, koaxiol elektrischgereizten Meerschweinchenileum. Arzneimittelforschung. 1971 Oct;21(10):1580–1584. [PubMed] [Google Scholar]
- Drew G. M. Pharmacological characterization of the presynaptic alpha-adrenoceptors regulating cholinergic activity in the guinea-pig ileum. Br J Pharmacol. 1978 Oct;64(2):293–300. doi: 10.1111/j.1476-5381.1978.tb17303.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Fielding S., Wilker J., Hynes M., Szewczak M., Novick W. J., Jr, Lal H. A comparison of clonidine with morphine for antinociceptive and antiwithdrawal actions. J Pharmacol Exp Ther. 1978 Dec;207(3):899–905. [PubMed] [Google Scholar]
- Geyskes G. G., Boer P., Dorhout Mees E. J. Clonidine withdrawal. Mechanism and frequency of rebound hypertension. Br J Clin Pharmacol. 1979 Jan;7(1):55–62. doi: 10.1111/j.1365-2125.1979.tb00897.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Gillan M. G., Kosterlitz H. W., Robson L. E., Waterfield A. A. The inhibitory effects of presynaptic alpha-adrenoceptor agonists on contractions of guinea-pig ileum and mouse vas deferens in the morphine-dependent and withdrawn states produced in vitro. Br J Pharmacol. 1979 Aug;66(4):601–608. doi: 10.1111/j.1476-5381.1979.tb13700.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Gold M. S., Pottash A. L., Sweeney D. R., Kleber H. D. Clonidine detoxification: a fourteen-day protocol for rapid opiate withdrawal. NIDA Res Monogr. 1979;27:226–232. [PubMed] [Google Scholar]
- Gold M. S., Redmond D. E., Jr, Kleber H. D. Clonidine in opiate withdrawal. Lancet. 1978 Apr 29;1(8070):929–930. doi: 10.1016/s0140-6736(78)90699-2. [DOI] [PubMed] [Google Scholar]
- Gyand E. A., Kosterlitz H. W. Agonist and antagonist actions of morphine-like drugs on the guinea-pig isolated ileum. Br J Pharmacol Chemother. 1966 Sep;27(3):514–527. doi: 10.1111/j.1476-5381.1966.tb01864.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Hansson L., Hunyor S. N., Julius S., Hoobler S. W. Blood pressure crisis following withdrawal of clonidine (Catapres, Catapresan), with special reference to arterial and urinary catecholamine levels, and suggestions for acute management. Am Heart J. 1973 May;85(5):605–610. doi: 10.1016/0002-8703(73)90165-8. [DOI] [PubMed] [Google Scholar]
- Kosterlitz H. W., Watt A. J. Kinetic parameters of narcotic agonists and antagonists, with particular reference to N-allylnoroxymorphone (naloxone). Br J Pharmacol Chemother. 1968 Jun;33(2):266–276. doi: 10.1111/j.1476-5381.1968.tb00988.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Laverty R., Roth R. H. Clonidine reverses the increased norepinephrine turnover during morphine withdrawal in rats. Brain Res. 1980 Jan 27;182(2):482–485. doi: 10.1016/0006-8993(80)91209-3. [DOI] [PubMed] [Google Scholar]
- Meyer D. R., El-Azhary R., Bierer D. W., Hanson S. K., Robbins M. S., Sparber S. B. Tolerance and dependence after chronic administration of clonidine to the rat. Pharmacol Biochem Behav. 1977 Sep;7(3):227–231. doi: 10.1016/0091-3057(77)90138-1. [DOI] [PubMed] [Google Scholar]
- North R. A., Karras P. J. Opiate tolerance and dependence induced in vitro in single myenteric neurones. Nature. 1978 Mar 2;272(5648):73–75. doi: 10.1038/272073a0. [DOI] [PubMed] [Google Scholar]
- Oates H. F., Stoker L. M., Monaghan J. C., Stokes G. S. Withdrawal of clonidine: effects of varying dosage or duration of treatment on subsequent blood pressure and heart rate responses. J Pharmacol Exp Ther. 1978 Aug;206(2):268–273. [PubMed] [Google Scholar]
- Reid J. L., Wing L. M., Dargie H. J., Hamilton C. A., Davies D. S., Dollery C. T. Clonidine withdrawal in hypertension. Changes in blood-pressure and plasma and urinary noradrenaline. Lancet. 1977 Jun 4;1(8023):1171–1174. doi: 10.1016/s0140-6736(77)92715-5. [DOI] [PubMed] [Google Scholar]
- Riordan C. E., Kleber H. D. Rapid opiate detoxification with clonidine and naloxone. Lancet. 1980 May 17;1(8177):1079–1080. doi: 10.1016/s0140-6736(80)91516-0. [DOI] [PubMed] [Google Scholar]
- Sabol S. L., Nirenberg M. Regulation of adenylate cyclase of neuroblastoma x glioma hybrid cells by alpha-adrenergic receptors. II. Long lived increase of adenylate cyclase activity mediated by alpha receptors. J Biol Chem. 1979 Mar 25;254(6):1921–1926. [PubMed] [Google Scholar]
- Sparber S. B., Meyer D. R. Clonidine antagonizes naloxone-induced suppression of conditioned behavior and body weight loss in morphine-dependent rats. Pharmacol Biochem Behav. 1978 Sep;9(3):319–325. doi: 10.1016/0091-3057(78)90292-7. [DOI] [PubMed] [Google Scholar]
- Tanaka T., Starke K. Binding of 3H-clonidine to an alpha-adrenoceptor in membranes of guinea-pig ileum. Naunyn Schmiedebergs Arch Pharmacol. 1979 Nov;309(3):207–215. doi: 10.1007/BF00504752. [DOI] [PubMed] [Google Scholar]
- Tayo F. M. Prejunctional inhibitory alpha-adrenoceptors and dopaminoceptors of the rat vas deferens and the guinea-pig ileum in vitro. Eur J Pharmacol. 1979 Sep 15;58(2):189–195. doi: 10.1016/0014-2999(79)90011-6. [DOI] [PubMed] [Google Scholar]
- Tseng L. F., Loh H. H., Wei E. T. Effects of clonidine on morphine withdrawal signs in the rat. Eur J Pharmacol. 1975 Jan;30(1):93–99. doi: 10.1016/0014-2999(75)90208-3. [DOI] [PubMed] [Google Scholar]
- Vetulani J., Bednarczyk B. Depression by clonidine of shaking behaviour elicited by nalorphine in morphine-dependent rats. J Pharm Pharmacol. 1977 Sep;29(9):567–569. doi: 10.1111/j.2042-7158.1977.tb11401.x. [DOI] [PubMed] [Google Scholar]
- Washton A. M., Resnick R. B., Rawson R. A. Clonidine hydrochloride: a nonopiate treatment for opiate withdrawal. NIDA Res Monogr. 1979;27:233–239. [PubMed] [Google Scholar]
