These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: The effects of idazoxan and other alpha 2-adrenoceptor antagonists on urine output in the rat.
    Author: Jackson HC, Griffin IJ, Birkett SD, Nutt DJ.
    Journal: Br J Pharmacol; 1992 Jun; 106(2):443-6. PubMed ID: 1356562.
    Abstract:
    1. In normally-hydrated Wistar rats the alpha 2-adrenoceptor antagonist, idazoxan (1, 3, 10 mg kg-1 i.p.), increased urine output during the 6 h following injection. 2. The more selective and specific alpha 2-adrenoceptor antagonist, RX811059 (0.3, 1, 3 mg kg-1 i.p.), and the peripherally-acting alpha 2-adrenoceptor antagonist, L-659,066 (1, 3, 10 mg kg-1 i.p.), had no effect on urine output in normally-hydrated animals. 3. In rats given a 25 ml kg-1 water-load orally, idazoxan (10 mg kg-1, i.p.) produced an initial antidiuretic response which was followed by an increase in urine output which was apparent 4 and 6 h after drug administration. 4. RX811059 (1, 3 mg kg-1 i.p.) and L-659,066 (3, 10 mg kg-1 i.p.) significantly decreased urine output in water-loaded rats in the 2 h after injection. 5. The antidiuretic effects of L-659,066 were attenuated in Brattleboro rats which are deficient in vasopressin; only the highest dose (10 mg kg-1 i.p.) decreased urine output, and this was only a small response in comparison with its virtual abolition of urine output in water-loaded Wistar rats. 6. The results with the selective alpha 2-adrenoceptor antagonists in Wistar and Brattleboro rats suggest that alpha 2-adrenoceptors in the periphery may play a physiological role in the control of water balance through a mechanism which involves vasopressin. 7. The paradoxical diuretic effects of idazoxan contrast with the effects of the other alpha 2-adrenoceptor antagonists and therefore may be attributed to a property of this compound unrelated to alpha 2-adrenoceptor blockade.
    [Abstract] [Full Text] [Related] [New Search]