Huntington’s disease is an inherited degenerative disease that usually appears in middle age and results in atrophy or loss of neurons in the caudate nucleus, putamen, and cerebral cortex.
It is characterized by arrhythmic, rapid muscular contractions (chorea), emotional disturbance, and dementia (impairment in intellectual and social ability). Animal studies suggest that cannabinoids have antichoreic activity, presumably because of stimulation of CB1 receptors in the basal ganglia.(129,168)
On the basis of positive results in one of four Huntington’s disease patients, CBD and a placebo were tested in a double-blind crossover study of 15 Huntington’s disease patients who were not taking any antipsychotic drugs. Their symptoms neither improved nor worsened with CBD treatment. (27,164)
The effects of other cannabinoids on patients with Huntington’s disease are largely unknown. THC and other CB1 agonists are more likely candidates than CBD, which does not bind to the CB1 receptor. Those receptors are densely distributed on the very neurons that perish in Huntington’s disease.(152) Thus far there is little evidence to encourage clinical studies of cannabinoids in Huntington’s disease.
27. Consroe P, Laguna J, Allender J, Snider S, Stern L, Sandyk R, Kennedy K, Schram K. 1991. Controlled clinical trial of cannabidiol in Huntington’s disease. Pharmacology, Biochemistry and Behavior (New York) 40:701-708.
129. Miller AS, Walker JM. 1995. Effects of a cannabinoid on spontaneous and evoked neuronal activity in the substantia nigra pars reticulata. European Journal of Pharmacology 279:179-185.
152. Richfield EK, Herkenham M. 1994. Selective vulnerability in Huntington’s disease: Preferential loss of cannabinoid receptors in lateral globus pallidus. Annals of Neurology 36:577-584.
164. Sandyk R, Consroe P, Stern P, Biklen D. 1988. Preliminary trial of cannabidiol in Huntington’s disease. Chesher G, Consroe P, Musty R., Editors, Marihuana: An International Research Report. Canberra: Australian Government Publishing Service.
168. Sanudo-Pena MC, Walker JM. 1997. Role of the subthalamic nucleus in cannabinoid actions in the substantia nigra of the rat. Journal of Neurophysiology 77:1635-1638.