Ethanol physiologic effects

Vasopressin is a peptide hormone produced by the hypothalamus and secreted by the posterior pituitary in response to stimulation. Normal stimuli for vasopressin release are hyperosmolarity and hypovolemia, with thresholds for secretion of greater than 280 mOsm/kg and greater than 20% plasma volume depletion. A number of other stimuli, such as pain, nausea, epinephrine, and numerous drugs, induce release of vasopressin. Vasopressin release is inhibited by volume expansion, ethanol, and norepinephrine. The physiological effect of vasopressin is to promote free water clearence by altering the permeability of the renal collecting duct to water. In addition, it has a direct vasoconstrictor effect. Consequently, vasopressin results in water retention and volume restoration. In patients with septic shock, vasopressin is appropriately secreted in response to hypovolemia and to elevated serum osmolarity (R14). 

Solution-based systems are common to both nebulizers and nasal formulations. In general, water will form the greatest fraction of the formulation, but, in some cases, cosolvents such as ethanol and propylene glycol may be added for increased stability. Acidifying and alkalizing excipients may also be added to optimize pH from the perspective of the drug stability as well as the physiological effect on the airways. Similarly, iso-osmotic and iso-tonic solutions are preferred. 

Caution The physiological effects of ethanol ingestion are different from those of other alcohols. Even ethanol must be used with extreme caution, but the other alcohols are deadly poisonous if ingested. 

The Pictet-Spengler reactions between epinephrine (noradrenalin) and formaldehyde and acetaldehyde have been investigated. The products from the reaction with acetaldehyde (Scheme 45) may be responsible for some of the physiological effects of ethanol. 

More recent research has added details to Shakespeare s enumeration—see the bracketed additions to the Porter s words above and the section on organ systems below—but the most noticeable consequences of the recreational use of ethanol stiU are weU summarized by the gregarious and garrulous Porter, whose delighted and devilish demeanor demonstrates a frequently observed influence of modest concentrations of ethanol on the CNS. The sections below detail ethanol s effects on physiological systems. 

Rush CR. Pretreatment witii hydromorphone, a ja-opioid agonist, does not alter the acute behavioral and physiological effects of ethanol in humans. Alcohol Clin Exp Res (2001) 25, 9-17. 

Taherzadeh MJ. (1999). Ethanol from lignocellulose physiological effects of inhibitors and fermentation strategies. Department of Chemical Reaction Engineering. Goteborg, Sweden, Chalmers University of Technology. 

The effect is mainly due to the inhibition of NAD+-dependent aldehyde dehydrogenase (ALDH) which causes an accumulation of acetaldehyde in the body after ethanol ingestion [17]. The compound responsible for the physiological activity of C. atramentarius is coprine 16, a AT -(l-hydroxycyclopropyl)-L-glutamic acid amide which has been isolated and synthesized, [16a,b]. Thus, when fed... 

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