Thread: ephedrine help
07-13-2004, 04:30 PM #1
ok, i know that ephedrine and pseudoephedrine are both chemically almost exactly identical, but what i'm not sure of is biological activity differences between the 2 of them. would pseudo have the same beta-2 agonist properties as regular ephedrine that help with weight loss? please just give me a direct answer, it would be GREATLY appreciated
i'm an analytical chemist,,,,,, not a biologist
07-13-2004, 05:22 PM #2
Ive got some good info in one of my text books but it pretty much says the same thing as this:
Introduction to ephedra and ephedrine alkaloids
The Chinese botanical ephedra, or ma-huang, is sold as a dietary supplement in the United States. Ephedra is the common name for three principal species: Ephedra sinica, Ephedra equisentina, and Ephedra intermedia . The active compounds in the plant's stem (about 1.32% by weight) are the phenylalanine-derived alkaloids ephedrine, pseudoephedrine, phenylpropanolamine (norephedrine), and cathine (norpseudoephedrine) [3,4].
Alkaloid content and composition vary by species and growth conditions [5-7]; total alkaloid content can vary from 0.5% to 2.3%. Ephedrine, the most potent alkaloid, can account for up to 90% of the total alkaloid content and pseudoephedrine can account for up to 27% [3,8,9]. The pharmacologic activity of an ephedra sample depends on its alkaloid composition. North American ephedra species, such as E. nevadensis (known as Mormon tea), contain little or no ephedrine or other alkaloids .
Ephedrine is a mixed sympathomimetic agent that enhances the release of norepinephrine from sympathetic neurons and stimulates alpha and beta receptors . Ephedrine stimulates heart rate, thereby increasing cardiac output [11,12]. It causes peripheral constriction resulting in an increase in peripheral resistance that can lead to a sustained rise in blood pressure . It relaxes bronchial smooth muscle [11,12] and is used as a decongestant and for temporary relief of shortness of breath caused by asthma.
Ephedrine acts as a stimulant in the central nervous system [11,12]. Of the ephedra alkaloids, ephedrine is the most potent thermogenic agent. It may function as an anorectic by acting on the satiety center in the hypothalamus .
Ephedrine and pseudoephedrine are both beta adrenoceptor agonists, which means that they partially mimic the effects of having an adrenaline rush. "Partially," because they differ structurally from adrenaline enough that they don't perform all the actions that actual adrenaline would to the same degree--both ephedrine and pseudoephedrine, for example, elevate your heart rate and blood pressure less than adrenaline would. Ephedrine will do much more to dilate your bronchial passages and raise your body temperature (and metabolic rate) than psuedoephedrine will; pseudoephedrine, on the other hand, is more effective as a decongestant.
Caffeine, however, is a phosphodiesterase inhibitor, and phosphodiesterase is an enzyme that breaks down cAMP (cyclic adenosine monophosphate) which is a messenger chemical that is generated within the cell in response to the stimulation of a suitable receptor (such as a beta receptor excited by the presence of ephedrine). So, what caffeine does is to make the other stimulatory chemicals more effective--ephedrine switches the cellular processes on, caffeine makes them stay on longer.
So, yes, caffeine will cause pseudoephedrine to be more effective for keeping your nose clear than pseudoephedrine would be alone. Current research does not indicate that this is a major advantage in weight loss, however. So, you're much better off with ephedrine, which can be found in several OTC asthma medications (and it's not going to make much difference whether it's ephedrine HCL or ephedrine sulphate).
In the end ephedrine is the most potent of the alkaloids. And it is shown to have ergogenic effects only when it is ingested with drugs such as caffeine, theophylline (an asthma medication) and aspirin. Caffeine both lowers the threshold concrentraiton requierd for physiological effects and poetiates the physiological effects of ephedrine concentration.
Hope this helps.
07-13-2004, 07:31 PM #3
hey thanks a lot bro, your one of the first that has, or has been able to directly answer a question i have without all the bull**** inbetween!!!!!
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