Beta-adrenergic activity

It has by now been reasonably well established that an ethanolamine function appropriately linked to an aromatic ring is a prerequisite for beta adrenergic activity and/or antagonism. Examples have been met above where those two moieties are attached directly as well as examples where the funetions are separated by an oxymethylene fragment. It has reeently been found that beta blocking activity is retained even when a earbonyl is inserted between the extra oxymethylene... 

Beta-Adrenergic Activation as Trigger in Ischemic and Pharmacologic Preconditioning... 

The question arose whether these observed changes in cAMP, and by implication, beta-adrenergic activation, played any role in the cardioprotection of ischemic preconditioning. Using the beta-1 adrenergic blocker alprenolol 7.5 x 10 5M during... 

BETA-BLOCKERS ERGOT DERIVATIVES Three reported cases of arterial vasoconstriction and one of T BP occurred when ergotamine or methysergide was added to propanolol or oxprenolol Ergotamine can cause peripheral vasospasm, and absence of beta-adrenergic activity can t the risk of vasoconstriction Ergot derivatives and beta-blockers are often co-administered without trouble however, monitor BP at least weekly until stable (watch for t BP) and warn patients to stop the ergot derivative and seek medical attention if they develop cold, painful feet... 

Jordan R, Midgley JM, Thonoor CM, Williams CM. Beta-adrenergic activities of octopamine and synephrine stereoisomers on guinea-pig atria and trachea. J Pharm Pharmacol 1987 39(9) 752-754. 

F. Hyperkalemia and hypokalemia. A variety of drugs and toxins can cause serious alterations in the semm potassium level (Table 1-27). Potassium levels are dependent on potassium intake and release (eg, from muscles), diuretic use, proper functioning of the ATPase pump, serum pH, and beta-adrenergic activity. Changes in serum potassium levels do not always reflect overall body... 

B. Ephedrine and pseudoephedrine have both direct and indirect alpha- and beta-adrenergic activity but clinically produce mote beta-adrenergic stimulation than PPA or phenylephrine. 

B. Reversal of hypotension and tachycardia caused by excessive beta-adrenergic activity resulting from theophylline or caffeine overdose. 

The use of adrenaline drops to promote haemostasis during general anaesthesia induced with halo thane diould be avoided halothane, and also cyclopropane, cause the myocardium to become sensitized to beta adrenergic activity so that with the concomitant use of adrenaline there is a risk of cardiac arrhythmia. It is also to be noted that there is a greater likelihood of absorption into the systemic circulation when adrenaline drops are used in the presence of vascular tissue. 

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