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: Desipramine desensitizes beta-adrenergic signal transduction in salivary glands: differential regulation with age.
    Author: Scarpace PJ, Koller MM, Rajakumar G.
    Journal: Eur J Pharmacol; 1993 Sep 15; 247(1):65-72. PubMed ID: 8258362.
    Abstract:
    We previously reported that the tricyclic antidepressant, desipramine desensitizes beta-adrenergic signal transduction in parotid and submandibular salivary glands. To determine the consequences of repeated desipramine administration on beta-adrenergic signal transduction in salivary glands from aged rats and whether the recovery after drug withdrawal is impaired, we assessed the effects of 28-day desipramine administration and the reversibility of this treatment following a 15-day washout period on beta-adrenoceptors and adenylyl cyclase activity in parotid and submandibular glands from F-344 rats of 6, 12 and 24 months of age. beta-Adrenoceptors were also assessed in the cerebral cortex. Desipramine administration down-regulated receptor number and attenuated isoproterenol-stimulated adenylyl cyclase activity in all three ages of rats. However, the reduction in isoproterenol-stimulated adenylyl cyclase activity was greater than the loss of receptor number. Desipramine administration attenuated the efficacy of NaF-stimulated activity with no change in forskolin-stimulated adenylyl cyclase activity. These data suggest that in addition to desensitizing beta-adrenergic-mediated signal transduction, desipramine impaired G-protein-mediated adenylyl cyclase stimulation. The recovery from desipramine desensitization was age dependent. beta-Adrenoceptor density recovered more slowly in the cerebral cortex and the submandibular gland in 24-month-old rats than in 6-month-old rats. In contrast, in 12-month-old rats, there was a receptor up-regulation and adenylyl cyclase supersensitivity. These data indicate that the capacity for receptor modulation is age dependent and suggest that desipramine treatment may down-regulate stimulatory G protein.
    [Abstract] [Full Text] [Related] [New Search]