The structure of behavioral variation within a genotype.

Individual animals vary in their behaviors. This is true even when they share the same genotype and were reared in the same environment. Clusters of covarying behaviors constitute behavioral syndromes, and an individual's position along such axes of covariation is a representation of their personality.

Structure-activity relationship studies of four novel 4-aminopyridine K channel blockers.

4-Aminopyridine (4AP) is a specific blocker of voltage-gated potassium channels (K1 family) clinically approved for the symptomatic treatment of patients with multiple sclerosis (MS). It has recently been shown that [F]3F4AP, a radiofluorinated analog of 4AP, also binds to K1 channels and can be used as a PET tracer for the detection of demyelinated lesions in rodent models of MS. Here, we investigate four novel 4AP derivatives containing methyl (-CH), methoxy (-OCH) as well as trifluoromethyl (-CF) in the 2 and 3 position as potential candidates for PET imaging and/or therapy.