4.2a Serotonin. Even though increased dopamine in the brain reward system is generally thought to be the final common pathway for the reinforcing properties of drugs, other neurotransmitters such as serotonin are involved in the modulation of both drug self-administration and dopamine levels.ike other drugs of abuse, stimulants increase dopamine concentrations in the brain reward pathway (1,2,3,4,7). Stimulants such as cocaine, amphetamines, caffeine and nicotine all stimulate the brain reward pathway through slightly different mechanisms and increase dopamine to different extents.
1 Gout is a form of arthritis caused by excess uric acid in the bloodstream. 2  The symptoms of gout are due to the formation of uric acid crystals in the joints. 3  Gout most commonly affects the joint in the base of the big toe.4  Gout attacks often occur without warning in the middle of the night.ore detail and supporting information is in the main article. 1  Gout is a form of arthritis caused by excess uric acid in the bloodstream. 2  The symptoms of gout are due to the formation of uric acid crystals in the joints.
Gout facts. 1  Gout is a type of arthritis that causes inflammation, usually in one joint, that begins suddenly. 2  Gouty arthritis is caused by the deposition of crystals of uric acid in a joint. 3  Gout can cause symptoms and signs such as. 4  nodules under the skin called tophi, 5  joint redness, 6  swollen joints, 7  joint pain, Gout is a type of arthritis that causes inflammation, usually in one joint, that begins suddenly. 2  Gouty arthritis is caused by the deposition of crystals of uric acid in a joint. 3  Gout can cause symptoms and signs such as.