Possible Interaction: Adrenergic Beta-Antagonists and Melatonin

“On subsequent occasions they reversed this treatment effect with oral melatonin administration and found that propranolol and atenolol, beta-antagonists that inhibit the production of melatonin , had a therapeutic effect similar to that of light.”

“ beta-adrenergic blockers potently suppress melatonin production (Hanssen et al.”

“It is known that administration of beta-blockers reduces melatonin production, but the data showing clinical significance of melatonin reduction associated with beta-blockers administration are still contradictory.”

“Adjuvant melatonin may also improve sleep disruption caused by drugs known to alter normal melatonin production (e.g., β‐blockers and benzodiazepines).”

“Since inhibition of melatonin secretion by beta-adrenergic blockade reduces the nocturnal decline of cBT by 40% in women, experiments were performed to investigate whether the thermoregulatory effect of light is mediated by modifications of melatonin secretion in cycling women.”

“This inhibitory effect of MLT was completely blocked by the MT1/MT2 receptor antagonist luzindole, but not by the selective MT2 receptor antagonist 4P-PDOT, the selective 5-HT1A receptor antagonist WAY100635, or by the α2 adrenoceptor antagonist idazoxan.”

“The increases in cAMP by melatonin are inhibited by blocker of phospholipase C U73122, and addition of 6-Bz-cAMP increases cytosolic Ca2+ concentration, through PKA activation.”

“This … of melatonin was partially blocked in the presence of …(-10) to 10(-7) M), a specific blocker of the small conductance calcium-dependent potassium channel, but not in the presence of other potassium … like charybdotoxin (10(-8) M), glibenclamide (l0(-5) M), or tetraethylammonium (ODQ, 10(-4) M).”

“was administered one hour before lights went off (i.e. when beta blockade does not affect NST in this species) and both variables were measured for another 30 h. The beta blocker markedly augmented melatonin output of A. russatus under both photoperiod regimes.”

“It is concluded that endogenous MEL effectively protects rat PBL from adrenergic immunosuppression, and that beta-blockers enhance the immunosuppressive property of alpha 2-adrenergic agents via blocking the night-time release of MEL.”

“Since melatonin (MEL) reportedly has stress-protective effects … several immune functions, and since the release of MEL from the pineal gland is inhibited by beta-blockade , we tested the effect of MEL substitution on T- and B-cell mitogen responses of PBL in rats treated with two s.c.”