Epinephrine causing

The third important feature distinguishing catecholamines from neu-ronally released norepinephrine involves epinephrine s affinity for -receptors. Norepinephrine has a very limited affinity for these receptors. Therefore, circulating epinephrine causes effects that differ from those of direct sympathetic innervation, including ... 

Thus, epinephrine causes a rapid response toward net glycogen breakdown to provide for the energy needs of muscle. 

A small dose of epinephrine causes a fall in mean and diastolic pressure with little or no effect on systolic pressure. This is due to the net decrease in total peripheral resistance that results from the predominance of vasodilation in the skeletal muscle vascular bed. The intravenous infusion or subcutaneous administration of epinephrine in the range of doses used in humans generally increases the systolic pressure, but the diastolic pressure is decreased. Therefore, the mean pressure may decrease, remain unchanged, or increase slightly, depending on the balance between the rise in systolic and fall in diastolic blood pressures (Rg. 10.4). 

The cardiac effects of epinephrine are due to its action on p-adrenoceptors in the heart. The rate and contractile force of the heart are increased consequently, cardiac output is markedly increased. Because total peripheral resistance is decreased, the increase in cardiac output is largely responsible for the increase in systolic pressure. Since epinephrine causes little change in the... 

SYMPATHOMIMETICS-EPINEPHRINE ANTIDIABETIC DRUGS May t antidiabetic therapy requirement Epinephrine causes the release of glucose from the liver and is an important defence/homeostatic mechanism. Hyperglycaemia may occur due to an antagonistic effect Larger doses of antidiabetic therapy may be needed during the period of epinephrine use, which is usually in the short term or in emergency situations... 

Figure 20-2. The mobilization of glycogen in the liver in response to hormonal signals. Binding of the hormones glucagon and/or epinephrine causes the activation of adenylate cyclase resulting in the production of cyclic AMP, which activates protein kinase A. By phosphorylation reactions, protein kinase A inactivates glycogen synthase, activates a cascade that results in active glycogen phosphorylase, and produces an active inhibitor of protein phosphatase 1.

The old advantages of epinephrine may be a disadvantage in modem western culture, and be a link between stress or coronary heart disease. In modem-day stress, when epinephrine is released, it is usually not a case of fight-or-flight, but more a problem of meeting deadlines or mental pressures. Thus, the released epinephrine causes the metabolic aspects previously described. The release of fatty acids from the adipose may be particularly detrimental. 

Epinephrine causes increases in cAMP in the adipose and muscle and increases in cytosolic Ca2+, via IP3, in the muscle and liver. The results in the adipose are similar to that of glucagon. The increased Ca2+ in the liver leads to increased glycogenolysis and release of glucose into the blood. The increased cAMP and Ca2+ in the muscle leads to increased glycogenolysis and G-6-P formation. The increased Ca2+ may aid in more effective contraction. The effects of increased fatty acids from the adipose has similar effects on liver and muscle, as in the case of glucagon. 

Glucagon and epinephrine cause fat breakdown - leads to fatty acid accumulation... 

Epinephrine as an adjunct in local anesthesia Vasocoirstriction respoitse to epinephrine causes local hemostasis, inhibiting distribution of local anesthetic away from the site of injection. 

In the intact goose intravenous injection of epinephrine caused a modest, but statistically significant elevation of plasma FFA. Norepinephrine also caused an elevation of FFA in the goose, but the effect was smaller than that of epinephrine and much smaller than the effects reported in the dog. Continuous infusion of norepinephrine caused elevation of plasma FFA in the goose, but the effect was much smaller than that observed in dogs under comparable conditions. 

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