VPT 321: Veterinary Neuropharmacology (2+1) copy 1

PSYCHOSTIMULANTS

Amphetamine , d-amphetamine and methylamphetamine

• Act by releasing noradrenaline and dopamine from vesicles
• Increases mental activity

Methylphenidate 

• Similar to Amphetamine but superior
• Can be used for improving attention and learning

Methylxanthines – Caffeine, theophylline and theobromine

• Caffeine in coffee beans – 1%
• Theophylline and caffeine in tea leaves – 3%
• Stimulate CNS, dilate blood vessels and promote diuresis
• Caffeine  irritates CNS cortex by blockade of adenosine receptors, induce cAMP (inhibit phosphodiesterase, enzyme that degrades cAMP)
• Rarely used in animals
• Migraine
• Apnoea in infants
• Theophylline useful as a bronchodilator

4 – Aminopyridine – antagonist to d-tubocurarine (nicotinic blocker)Antagonizes several CNS depressants such as pancuronium, diazepam-ketamine, neuroleptanalgesia etc.

Yohimbine – alpha₂ antagonist – specific antagonist to xylazine poisoning but also other agents

Tolazoline - alpha₂ antagonist and other mood elevators.