Possible Interaction: Melatonin and Phenylephrine

“ Melatonin reversed the blood pressure augmented by TCDD and decreased the contractile responses to phenylephrine in aorta.”

“A main factor analysis in the factorial ANOVA indicated that age and operation augmented, and melatonin decreased, aortic ring contractility response to phenylephrine.”

“Intracerebroventricular infusion of phenylephrine (12.2 μmol/kg/hr) induced more than 10‐fold increase in release of melatonin into the duodenal lumen and an increase in HCO secretion from 7.6 ± 0.5 to 18.6 ± 2.1 μEq/cm/hr.”

“In this study, we demonstrate that MT pretreatment prevents the hyporeactivity to phenylephrine in vivo and in aorta rings collected from rats treated with the endotoxin.”

“ Melatonin decreased phenylephrine‐induced vasoconstriction in MDR and counteracted the effect of high glucose in SDR.”

“ MEL inhibits the contractile responses of aortic rings to NA and PHE.”

“Moreover, MEL (10(-4) M) had a significant inhibitory effect on the contractile responses of aortic rings to both NA and PHE.”

“In arterial ring segments isolated from female rats, melatonin potentiated, in a concentration-dependent manner, contractions produced either by adrenergic nerve stimulation or by phenylephrine.”

“In conclusion, the results show that melatonin produced an enhancement of the contractile response elicited by phenylephrine in the perfused rat tail artery.”

“ Melatonin , 2-iodomelatonin, 6-chloromelatonin, and S20098 (N-[2-(7-methoxy-1-naphthyl)ethyl]acetamide) produced a concentration-dependent enhancement of the vasoconstrictor response evoked by 1 microM phenylephrine with a rank order of potency compatible with the pharmacologic profile defined for high-affinity melatonin receptors.”

“ Melatonin (100 nM) potentiated contractile responses to both adrenergic nerve stimulation and α1‐adrenoceptor stimulation by phenylephrine.”

“In cultured aortic vascular smooth muscle cells, the basal and phenylephrine induced inositol phosphate formations were greater in SHR, and the melatonin pretreatment dose dependently attenuated the phenylephrine responses in cells from both WKY and SHR.”