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: Inhibitors of prostaglandin synthesis reverse the effects of chronic beta-receptor blockade to attenuate adrenergic neurovascular transmission in dogs. Author: Daniell HB, Webb JG, Walle T, Oatis JE, Gaffney TE. Journal: J Cardiovasc Pharmacol; 1988 Sep; 12(3):300-7. PubMed ID: 2464102. Abstract: The effects of acute and chronic treatment with beta-adrenergic receptor blocking drugs on peripheral adrenergic neurovascular transmission were investigated. Experiments were performed using the blood perfused gracilis muscle preparation in control dogs and in animals treated with single or repeated doses of beta-receptor antagonists. After 7 days of d,l-propranolol, l-propranolol, or atenolol administration, the arterial pressor response to sympathetic nerve stimulation was significantly reduced in treated dogs (p less than 0.05) when compared with control- or d-propranolol-treated animals. In comparison, acute beta blockade produced by a single intravenous dose of propranolol had no effect on the pressor response to nerve stimulation. Inhibition of fatty acid-cyclooxygenase activity by indomethacin or piroxicam enhanced the vasoconstrictor response to sympathetic nerve stimulation in chronic d,l-propranolol-, l-propranolol-, and atenolol-treated dogs, but had no effect on vascular neurotransmission in control-, chronic d-propranolol-, or acutely d,l-propranolol-treated animals. The vasoconstrictor response to intraarterial phenylephrine was not significantly altered by chronic propranolol treatment, and measurement of norepinephrine overflow during sympathetic nerve stimulation failed to reveal any difference in neurotransmitter release between control- and propranolol-treated dogs. The results indicate that chronic but not acute beta-adrenergic receptor blockade alters signaling at the neurovascular synapse to diminish adrenergic transmission. This effect does not appear to result from a change in postsynaptic alpha 1 receptors or from a decrease in norepinephrine release.(ABSTRACT TRUNCATED AT 250 WORDS)[Abstract] [Full Text] [Related] [New Search]