Ephedrine smooth muscle

Ephedrine increases systolic and diastolic blood pressure heart rate is generally not increased. Contractile force of the heart and cardiac output are both increased. Ephedrine produces bronchial smooth muscle relaxation of prolonged duration when administered orally. Aside from pupillary dilation, ephedrine has little effect on the eye. 

Ephedrine is an alkaloid obtained from Ephedra vulgaris plant. It act indirectly and directly on a and P receptors. It increases blood pressure both by peripheral vasoconstriction and by increasing the cardiac output. Ephedrine also relaxes the bronchial smooth muscles. 

It is a synthetic compound with structural similarity to ephedrine and is available in racemic and dextro isomers. It increases the systolic and diastolic blood pressure. Amphetamine is a potent CNS stimulant and causes alertness, insomnia, increased concentration, euphoria or dysphoria and increased work capacity. Amphetamine produces wakefulness and improved physical performance. It contracts the sphincter of the bladder and relaxes the bronchial smooth muscle in large doses. Amphetamines are drugs of abuse and can produce behavioural abnormalities and can precipitate psychosis. It can produce psychological but no physical dependence. 

CNS, smooth muscle T diuresis X- pit aggregation Available forms Daily t doses w/ max 3 g PO daily Contra Avoid in PRG lactation, CAD, hyperthyroidism, anxiety disorders d/t high, caffeine content Notes/SE Insomnia, tach, anxiety, N/V, HA, HTN, Sz Interactions T Effects OF anticoagulants, anti-pits, BBs, bron-choclilators T risk of hypertensive crisis W/ MAOIs T effects W/ cimetidine, ciprofloxacin, ephedrine, hormonal contraceptives, dieophylline, cola, coffee X-effects OF adenosine, antihypertensives, benzodiazepines, Fe, X- effects W/ smoking EMS Tinctures contain EtOH may exacerbate GI disorders HTN T effects of anticoagulants and BBs... 

A number of plants containing furoquinoline alkaloids have been used medicinally, but the alkaloids themselves have found no place in medicine. Skimmianine (159) has been shown to potentiate adrenalin in cats, to relax intestinal muscle, and to raise the tone of striated muscle it has much in common with ephedrine. Dictamnine (158) strongly contracts smooth muscle and stops the isolated frog heart in diastole. Quite recently it has been shown that certain furoquinoline alkaloids are phototoxic to some bacteria and yeasts in long-wavelength UV light (81MI31701). 

The phenomena of systemic cocaine poisoning are largely those of sympathetic stimulation but not as consistently as with epinephrine. The sympathetic stimulation is mainly central (midbrain) but partly peripheral. The chief manifestations of sympathetic stimulation are (1) sensitization to epinephrine (but antagonization to ephedrine) by peripheral action, (2) mydriasis and slight exophthalmos by central and peripheral action, and (3) cardiac acceleration (chiefly central). Other sympathetic symptoms are constriction of the blood vessels, erection of hair, and relaxation of the intestines. High concentrations of cocaine paralyze all smooth muscles. Procaine also produces... 

Ephedrine stimulates both a- and p-receptors, causing increased heart rate, unchanged or augmented stroke volume, enhanced cardiac output, and increased blood pressure. It causes relaxation of smooth muscle of bronchi and gastrointestinal tract, stimulation of cerebral cortex, and pupil dilation. 

At first, ephedrine was assumed to have a mechanism of action similar to that of epinephrine, acting through the same receptive mechanism. Later, as it was found that not all the effects of epinephrine could be duplicated by ephedrine, it was conjectured that some of its effects were due to direct excitation of smooth muscle. 

The smooth muscle of the bronchial tree is relaxed by ephedrine. Compared with epinephrine, the action of ephedrine is slow in onset, becoming complete only an hour or more after administration. Ephedrine prevents histamine-induced bronchoconstriction in patients with asthma. 

In general, ephedrine produces the same effects on smooth muscle as epinephrine. Inhibition of the intact gastrointestinal musculature and contraction of the splenic capsule and of pilomotor muscles are produced. Ephedrine has the same myometrial and urinary bladder actions as does epinephrine. 

The basic pharmacological action of Ephedrine is that of a sympathomimetic. It does not contain a catechol moiety and is effective after oral administration. The drug stimulates heart rate and cardiac output and variably increases peripheral resistance as a result, ephedrine usually increases blood pressure. Stimulation of the a-adrenergic receptors of smooth muscle cells in the bladder base may increase resistance to the outflow of urine. Activation of S-adrenergic receptors in the lungs promotes bronchodilation. Ephedrine stimulates the cerebral cortex and subcortical centers to produce its effects in narcolepsy and depressive states. 

Ephedrine is also an a agonist and, as such, is capable of stimulating bladder smooth muscle. At one time, it was used to promote urinary continence (65,66). In animal models, when compared to norepinephrine, ephedrine is a relatively weak a-adrenergic agonist, possessing less than one-third the activity of norepinephrine (67). Ephedrine s usefulness as a bronchodila-tor is limited by the number of 3-receptors on the bronchi. The number of p-... 

Answer E. Tachyphylaxis, a rapid loss of pharmacologic activity, frequently occurs with indirect-acting sympathomimetics such as amphetamine, ephedrine, and pseudoephedrine. These drugs act to release NE from the mobile pool in sympathetic nerve endings. With excessive use of these agents, the NE stores may become depleted, resulting in a decreased response of vascular smooth muscle in terms of vasoconstriction. 

Long-acting sympathomimetics such as ephedrine are sometimes used to improve urinary continence in children with enuresis and in the elderly. This action is mediated by alpha receptors in the trigone of the bladder and, in men, the smooth muscle of the prostate. 

One of these is Ephedrine where the carbon chain plus aminic tail is CH(0H)CH(CH3)NH(CH3), looking like a close brother of PEA. Ephedrine is a natural product extracted from a plant called Ephedra and used in traditional Chinese medicine. It can also be made in the laboratory. Ephedrine is administered as a stimulant, appetite suppressant, and concentration aid. It seems to work by increasing the activity of norepinephrine. It is used, for example, by professional weightlifters and athletes. Another close brother of PEA is pseudoephedrine, which is a chiral isomer of ephedrine, and it causes vasoconstriction (constriction of blood vessels) and relaxation of smooth muscles, thus leading to bronchial dilation. It is administered for nasal/sinus congestion and difficulty in breathing. Methamphetamine is another... 

Notably, pseudoephedrine is a diastereomer of ephedrine and considerably racemic ephedrine (dl-ephedrine) has not been found naturally, however, it is prepared synthetically and is inactive for commercial purposes. Ephedrine and pseudoephedrine are completely stable compounds under changing temperature conditions, but they are quite unstable when exposed to sunlight or in the presence of oxygen pressure [2]. The unique molecular structure of ephedrine causes its different stereoisomers to be valuable for pharmaceutical applications such as nasal decongestant, pupil dilator, bronchodilator, and central nervous system stimulant. Ephedrine is a sympathomimetic substance and the principle mechanism of ephedrine activity is its influence, by enhancing the activity of noradren-alin, on post-synaptic a- and (3-receptors in the nervous system. Stimulation of a 1-adrenergic receptors produces contraction of vascular smooth muscle. 

Ephedrine occurs in white, rosette, or needle crystals, or as an unctuous mass. It is soluble in water, alcohol, chloroform, ether, and in liquid petrolatum, the latter solution being turbid if the ephedrine is not dry. Ephedrine melts between 34 and 40°C, depending upon the amount of water it contains it contains not more than 0.1% of ash its solutions are alkaline to litmus it readily forms salts with acids and it responds to the usual tests for alkaloids. Ephedrine excites the sympathetic nervous system, depressing smooth and cardiac muscle action, and produces effects similar to those of epinephrine. It produces a rather long-lasting rise of blood pressure and mydriasis and diminishes hyperemia. The alkaloid may be used in 0.5 to 2% oil spray. 

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