Possible Interaction: Epinephrine and Hexamethonium

“In cats, rats and pigeons, concentrations of hexamethonium , tetra‐ethylammonium and pentolinium ions too low to influence transmission in autonomic ganglia potentiate the pressor effects of adrenaline , noradrenaline and of reflex vasoconstriction.”

“Neither adrenalectomy nor adrenergic "blockade" prevented the positive inotropic response to hypoxia, and hexamethonium paradoxically sensitized the heart to epinephrine.”

“Endogenous acetylcholine (nerve stimulation)-induced epinephrine release was inhibited by hexamethonium but not atropine.”

“In either case, epinephrine release was inhibited by atropine as well as hexamethonium.”

“Second, pre-treatment with the nicotinic receptor antagonist hexamethonium inhibited the electrically evoked secretion of adrenaline and noradrenaline.”

“ Hexamethonium (10-100 microM) markedly inhibited the ES-induced increases in Epi and NE output from adrenal glands of SHRs and WKY rats.”

“The adrenal NA and Adr responses to 10(3) microM ACh between 84 and 137 days were reduced by up to 99% after the addition of hexamethonium.”

“ Hexamethonium markedly reduced the ANS response to insulin injection ( ΔEPI + 2130 ± 600 pM, P < 0.025 vs. control) despite a similar fall of plasma glucose (Δ −4.1 ± 0.2 mM) and a lower nadir (0.6 ± 0.1 mM).”

“Blockade of neural input to the adrenal by hexamethonium (25 mg/kg) reduced but did not eliminate the increases in plasma norepinephrine and epinephrine concentrations in fetuses at 109-119 days gestation, while it completely abolished these responses in fetuses at 130-136 days gestation.”

“ Hexamethonium decreased in a dose-dependent manner the elevations in plasma adrenaline , corticosterone and glucose levels that were elicited by the 5-HT1A receptor agonist, 8-OH-DPAT (0.25 mg/kg).”

“The enhancement of PFC by epinephrine was completely blocked by preadministration with propranolol and hexamethonium , but not with phentolamine.”