Beta-Adrenergic Stimulation

One of the few examples of decreased susceptibility among elderly is the effect of catecholamines on the heart. There is a down-regulation of beta-adrenergic receptors and a reduced response to beta-adrenergic stimulation (Turnheim 1998). This results in decreased effect of betablockers on heart rate and stroke volume. In the elderly betablockers may be less effective than other drugs against hypertension and they should not be considered appropriate for first-line therapy of uncomplicated hypertension in the elderly (Grossman and Messerli 2002). 

Terrenoire, C., Lauritzen, I., Lesage, F., Romey, G., Lazdunski, M. A TREK-1-like potassium channel in atrial cells inhibited by beta-adrenergic stimulation and activated by volatile anesthetics, Circulation Research 2001, 89, 336-342. 

Lindemann, J.P., Jones, L.R., Hathaway, D.R., et al., 1983, beta-Adrenergic stimulation of phospholamban phosphorylation and Ca2+-ATPase activity in guinea pig ventricles. J Biol Chem, 258(1), pp 464-71. 

Talosi, L., Edes. I., and Kranias, E.G., 1993, Intracellular mechanisms mediating reversal of beta-adrenergic stimulation in intact beating hearts. Am J Physiol, 264(3 Pt 2), pp H791—7. 

Wegener, A.D., Simmerman, H.K., Lindemann, J.P., et al., 1989, Phospholamban phosphorylation in intact ventricles. Phosphorylation of serine 16 and threonine 17 in response to beta-adrenergic stimulation. J Biol Chem, 264(19), pp 11468-74. 

Asimakis, G.K., Inners-McBride, K., Conti, V.R., and Yang, C.J. 1994. Transient beta adrenergic stimulation can precondition the rat heart against post-ischaemic contractile dysfunction. Cardiovasc. Res. 28 1726-1734. 

Yabe, K., Ishishita, H., Tanonaka, K., and Takeo, S. 1998. Pharmacologic preconditioning induced by beta-adrenergic stimulation is mediated by activation of protein kinase C. J. Cardiovasc. Pharmacol. 32 962-968. 

Sims, C., and Harvey, R. D. 2004. Redox modulation of basal and beta-adrenergically stimulated cardiac L-type Ca2+ channel activity by phenylarsine oxide. Br. J. Pharmacol. 142 797-807. 

Perkins SN, Evans WS, Thorner MO, Cronin MJ (1983) Beta-adrenergic stimulation of growth hormone release from perifused rat anterior pituitary cells. Neuroendocrin 37 473-475... 

Wegener J, Zink S, Rosen P, Galla H (1999) Use of electrochemical impedance measurements to monitor beta-adrenergic stimulation of bovine aortic endothelial cells. Pflugers Arch 437 925-934... 

Cardiovascular 4 Myocardial sensitivity to beta-adrenergic stimulation 4 Baroreceptor activity 4 Cardiac output t Total peripheral resistance... 

Somatostatin Central nervous system, pancreatic delta cells, and enteroendocrine delta cells 1. Inhibits secretion of insulin, glucagon and PP (islets), and gastrin, secretin, GLP-1, and GLP-2 (in gut) 2. Reduces carbohydrate absorption from gut lumen 1. Luminal nutrients 2. GLP-1 3. GIP 4. PACAP 5. VIP 6. Beta-adrenergic stimulation... 

Novara M, Baldelli P, Cavallari D, Carabelli V, Giancippoli A, Carbone E. Exposure to cAMP and beta-adrenergic stimulation recruits Cav3 T-type channels in rat chromaffin cells through Epac cAMP-receptor proteins. J Physiol 2004 558(Pt 2) 433-49. 

Reproterol Is a b eta-phenethylamlnoalkylxanthlne recently marketed abroad. It represents a chemical hybrid of theophylline and either terbutallne or metaproterenol (Figure 4). This agent has a preferential impact on beta-adrenergic receptors and can be classified as a beta adrenergic stimulant (10). Reproterol Is claimed not to exhibit the CMS and cardiovascular effects typical of other beta-adrenergic stimulants, suggesting that the theophylline moiety may be Important to this molecule. 

Elderly Patients and Those Sensitive to Beta-adrenergic Stimulators An initial dosage of 2 mg three or four times a day is recommended for elderly patients and for those with a history of unusual sensitivity to beta-adrenergic stimulators. If adequate broncho dilation is not obtained, dosage may be increased gradually to as much as 8 mg three or four times a day. 

B. Specific drugs and antidotes. Hypotension, tachycardia, and ventricular arrhythmias are caused by excessive beta-adrenergic stimulation, and beta blockers are specific antagonists. Give propranolol (see p 496), 0.01-0.02 mg/kg IV, oresmolol (see p 443), 0.025-0.1 mg/kg/min IV. Use beta blockers cautiously in patients with a prior history of asthma or wheezing. 

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. 

A. Additive beta-adrenergic stimulation occurs in the presence of other sympathomimetic dmgs, theophylline, or glucagon. 

Levine, L. and Moskowitz, M.A. (1979). Alpha- and beta-adrenergic stimulation of arachidonic acid metabolism by cells in culture. Proc. Natl Acad. Sci. USA, 76, 6632-36... 

Ks Slow component of the delayed rectifier potassium current especially prominent in supporting repolarization (phase 3) with beta-adrenergic stimulation... 

Irigaray, P Ogier, V Jacquenet, S Notet, V Sibille, P Mejean, L et al. (2006). benzo[a]pyrene impairs beta-adrenergic stimulation of adipose tissue lipolysis and causes weight gain in mice a novel molecular mechanism of toxicity for a common food pollutant. FEBSJ, 273,1362-1372. 

Bennett WD, Chapman WF, Lay JC, Gerrity TR. Pulmonary clearance of inhaled particles 24 to 48 hours post deposition effect of beta-adrenergic stimulation. J Aerosol Med 1993 6 53-62. 

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