A 2000 Cochrane Review found that, compared to placebo, ketanserin did not provide significant relief for people suffering from Raynaud's phenomenon attacks in the setting of progressive systemic sclerosis (an autoimmune disorder). While the frequency of the attacks was unaffected by ketanserin, there was a reduction in the duration of the individual attacks. However, due to the significant adverse effect burden, the authors concluded that ketanserin's utility for this indication is likely unbeneficial.
An autoradiography study of the human cerebellum has found an increasing binding of 3H-ketanserin with age (from below 50 femtomol per milligram tissue at around 30 years of age to over 100 above 75 years). The same research team found no significant correlation with age in their homogenate binding study.
Ketanserin is a high-affinity non-selective antagonist of 5-HT2 receptors in rodents, with Ki values of 2–3 nM for the 5-HT2A receptor and 28 nM for the 5-HT2C receptor). In primates including humans however, ketanserin is a more selective antagonist of the 5-HT2A over the 5-HT2C receptor, with Ki values of 2–3 nM for the 5-HT2Areceptor and 130 nM for the 5-HT2C receptor. In addition to the 5-HT2 receptors, ketanserin is also a high affinity antagonist for the H1 receptor (Ki = 2 nM), and has measurable albeit relatively low affinity for a number of other receptors:
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^Pope, J; Fenlon, D; Thompson, A; Shea, B; Furst, D; Wells, G; Silman, A (2000). "Ketanserin for Raynaud's phenomenon in progressive systemic sclerosis". The Cochrane Database of Systematic Reviews (2): CD000954. doi:10.1002/14651858.CD000954. PMID10796396.
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