Alcohol tolerance
- alcohol tolerance due to liver adapting;
- by producing more enzymes that break down alcohol;
- oxidized by MEOS/microsomal ethanol oxidizing systems nerve cells in brain become less responsive;
Metabolism of alcohol #
- alcohol dehydrogenase;
- alcohol converted to acetaldehyde/ethanol;
- NAD – hydrogen carrier;
- ethane dehydrogenase;
- ethanol to acetic acid/acetate/ethanoic acid;
- acetate converted to acetyl coA;
- enters Krebs Cycle;
- respired to carbon dioxide and water;
- liver metabolises alcohol as an energy source rather than fat;
- catalase may also oxidize alcohol;
- MEOS used when blood alcohol concentration (BAC) is higher;
Long term consequences of alcohol consumption on the liver, brain and peripheral nervous system #
Liver
- inflammation;
- scarring/fibrous tissue;
- cirrhosis/hepatitis/jaundice/cancer;
- fatty liver;
- compression of blood vessels in liver (blood forced from portal veins into veins from oesophagus and rectum);
Brain
- loss of short term memory
- impaired judgement;
- confusion/disorientation/anxiety/hallucinations;
- impaired motor control;
- dementia;
- sleep disturbance/reduced REM sleep;
- shrinkage of brain cells;
- by alcohol induced dehydration;
- inhibits secretion of AHD so kidneys remove more water than normal ;
- hypoxia – low blood oxygen causes death of brain cells;
- low blood glucose levels cause death of brain cells
- blockage of brain capillaries;
- loss of intellectual functions e.g. calculations, learning;
- Korsakoff‘s psychosis, leading to loss of short term memory and learning ;
- Wernicke‘s encephalopathy leading to comma, disturbance of speech/walking, confusion;
- Neglecting of diet leading to Vitamin B1 deficiency – Leads to long term brain damage
Peripheral nervous system
- (poly) neuropathy (neurological disorder that occurs when many PNS throughout the body malfunction simultaneously);
- damage to sensory nerves;
- feeling cold, pains/cramps/numbness(partial/total lack of sensation)/tingling;
- starts in hands and spread to centre of body;
- damage to motor neurones;
- muscle wasting/weakness;
- damage to autonomic nerves;
- related to faintness/incontinence(involuntary urination/defecation)/impotence(powerlessness/feeble/weak)/blurred vision/poor control of gut;
- caused by Vitamin B1/thiamine deficiency;
- poor diet/all or most energy needs from alcohol so no balanced diet; – damage to axons;
Short term effects of alcohol consumption on the brain
- depressant;
- effects depends on blood alcohol concentration;
- depresses brain function;
- by inhibiting reticular activating system (RAS);
- therefore activity of cerebral cortex
- intellectual faculties diminished;
- loss of coordination/judgement/control over fine movement;
- g. slurred speech/staggering walking;
- depression of respiratory centres/death;
- relaxed feeling/increased confidence/reduced tension;
- loss of inhibitions;
- slower reaction time;
- loss of balance;
- at higher levels, comma;
Social problems associated with heavy alcohol drinking
- personal relationship affected/considerable stress caused to the family;
- social isolation from friends/neighbours/embarrassment;
- violence in marriage + marital breakdown;
- correlated with wife battering (half husbands involved frequently drink);
- aggressiveness + destruction of property;
- crime as means to finance drinking;
- drink-driving + traffic accidents;
- neglect of food intake;
- frequent changes of jobs/loss of employment;
- uncontrollable anger;
- sexual assault;
- grandiose behaviour;
- young single women getting pregnant;
- conflict between parents affect children;
- sexual abuse of children;
- child neglect/children more likely to need child guidance/help from social services;
- children left unattended more likely to have accidents;
- poverty resulting from money spent on alcohol;
- poverty resulting from loss of job;
- poor health leading to loss of income/premature death;
- g. repossession of home, default on hire purchase/mortgage repayment;
