Neurochemical investigation of an endogenous model of the "hyperkinetic syndrome" in a hybrid dog.

A telomian-beagle hybrid has been recently proposed as a possible model for the hyperkinetic syndrome. They resemble hyperkinetic children in their poor ability to respond with the appropriate behavior in an inhibitory training test. Two groups of hybrids could be differentiated, the behavior of one of which improved with amphetamine (“Responders”) and of the other did not (“Non responders”). In the present study, the levels of HVA, 5-HIAA, MOPEG-SO were measured in CSF and the levels of NA, DA, HVA, DOPAC⁴, 5-HIAA were assayed in brain tissues from different regions, taken under basal conditions from beagles and telomian-beagle hybrids. Responder hybrids had lower levels of NA, DA, HVA in brain and low HVA in CSF. Therefore, they can be distinguished biochemically as well as behaviorally from non-responder hybrids and beagles and may prove to be useful as models for study of the mechanism and the therapy of this syndrome.