PSYCHOTROPIC DRUGS

PSYCHOTROPIC DRUGS Structural Classification of the Nervous System Central Nervous System: consist of brain and spinal cord, which act as integrating and command centers of the nervous system. Peripheral Nervous System: it is the part of nervous system outside the CNS. They link all parts of the body by carrying impulses from sensory receptors to CNS and from the CNS to appropriate glands or muscles. Synaptic Transmission Excitatory postsynaptic potentials (EPSP) and Inhibitory postsynaptic potentials (IPSP) are inputs that depolarize/hyperpolarize the postsynaptic cell bringing it closer/away from firing an action potential. EPSP are caused by opening of channels that are permeable to Na and K. Neurotransmitters: Ach, Dopamine, Serotonin IPSP are caused by opening of Cl channels Neurotransmitters: GABA and Glycine Neurotransmitters Acetylcholine Serotonin Norepinephrine Dopamine GABA Glutamate Most drugs that affect the central nervous system (CNS) act by altering some step in the neurotransmitters mediating the physiological and pathological responses in neuropharmacology. Acetylcholine Myasthenia gravis is characterized by skeletal muscle weakness and fatigability resulting from a reduced number of Ach receptors on muscle end plate (due to autoimmune antibodies against acetylcholine receptors at neuromuscular junction). Diagnosis and treatment involves acetylcholine esterase inhibitors (neostigmine)- prolong the action of acetylcholine at muscle end plate. Ach esterase inhibitors (Tacrine)-Alzheimer’s Disease Anticholinergic (Benztropine) in Parkinson’s Disease