PHRM 311 Lecture Notes - Lecture 19: Time Perception, Psychotomimetic, Intraocular Pressure
Document Summary
19. 2 pharmacological actions of common drugs associated with sud (part 3) Prepared from the dried flowering tops and leaves. Hashish (2-20%) from the dried cannabis and compressed flowers, extracted for its resin hashish oil (15-80%) Exogenous cannabinoids in cannabis include a variety (>50) of active substances. 9-tetra-hydrocannabinol (thc) a powerful psychoactive substance; highest content in flowering tops, declining in the leaves, lower leaves, stems and seeds. Endogenous cannabinoids bind to cb1 receptors in cns : anandamide, 2-ag (2-arachidonoyl glycerol) Thc binds to cb receptors in the brain disinhibition of da neurons. By presynaptic inhibition of gaba neurons in the vta releases da in reward centers. Usually smoked and 3x more potent by this route compared to the oral route. Onset: seconds or minutes (smoking), within 30 min to 2 hrs (oral) Cns effect duration: 2-3 hrs (smoking), 5-12 hrs (oral) Long t1/2 (56 hours); metabolites present up to 18 days.
