Activation of alpha-1 adrenoreceptors of rat aorta by analogs of imidazoline

V. K. Lamba-Kanwal, A. Hamada, A. Adejare, M. T. Clark, Duane Miller, P. N. Patil

Research output: Contribution to journalArticle

10 Citations (Scopus)

Abstract

New analogs of desoxycatecholimidazoline were synthesized for elucidating the steric requirements for the activation of alpha-1 adrenoreceptors. The compounds tested on rat thoracic aorta in this study were: desoxycatecholimidazole with and without bridge carbon hydroxyl group, analogs of desoxycatecholimidazoline with fluorine substitution at position 2, 5 or 6 of the catechol ring and hydroxybenzyl group at carbon-4 of the imidazoline part of the molecule. The addition of a double bond in the imidazoline to give an imidazole results in a decrease in potency and the introduction of benzylic hydroxyl group also reduces its activity by 4- and 6-fold, respectively. 2-FLuoro and 5-fluoro catecholimidazoline possess full agonist activity; their potencies being even higher than the parent molecule. The 6-fluoro analog is a partial agonist inasmuch as it produces a response that is only 30% of the maximum response produced by other analogs of imidazoline. In the present study, 4-substituted imidazolines retain their agonist activity, although weaker than desoxycatecholimidazoline. The potency of R- and S-isomers of 4-substituted catecholbenzyl imidazoline were similar. Although these isomers exhibit apparent chemical similarity to catecholamines, small differences between the activity of stereoisomers indicate that the mode of interaction of these molecules at alpha adrenoreceptor may differ from that of stereoisomers of epinephrine.

Original languageEnglish (US)
Pages (from-to)793-797
Number of pages5
JournalJournal of Pharmacology and Experimental Therapeutics
Volume245
Issue number3
StatePublished - 1988
Externally publishedYes

Fingerprint

Imidazolines
Aorta
Stereoisomerism
Hydroxyl Radical
Carbon
Fluorine
Thoracic Aorta
Epinephrine
Catecholamines

All Science Journal Classification (ASJC) codes

  • Pharmacology

Cite this

Lamba-Kanwal, V. K., Hamada, A., Adejare, A., Clark, M. T., Miller, D., & Patil, P. N. (1988). Activation of alpha-1 adrenoreceptors of rat aorta by analogs of imidazoline. Journal of Pharmacology and Experimental Therapeutics, 245(3), 793-797.

Activation of alpha-1 adrenoreceptors of rat aorta by analogs of imidazoline. / Lamba-Kanwal, V. K.; Hamada, A.; Adejare, A.; Clark, M. T.; Miller, Duane; Patil, P. N.

In: Journal of Pharmacology and Experimental Therapeutics, Vol. 245, No. 3, 1988, p. 793-797.

Research output: Contribution to journalArticle

Lamba-Kanwal, VK, Hamada, A, Adejare, A, Clark, MT, Miller, D & Patil, PN 1988, 'Activation of alpha-1 adrenoreceptors of rat aorta by analogs of imidazoline', Journal of Pharmacology and Experimental Therapeutics, vol. 245, no. 3, pp. 793-797.
Lamba-Kanwal, V. K. ; Hamada, A. ; Adejare, A. ; Clark, M. T. ; Miller, Duane ; Patil, P. N. / Activation of alpha-1 adrenoreceptors of rat aorta by analogs of imidazoline. In: Journal of Pharmacology and Experimental Therapeutics. 1988 ; Vol. 245, No. 3. pp. 793-797.
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