[Effects of alpha-methyl-dopa on new born kitten sleep. Behavioral evolution during the first month post-birth...

The paradoxical sleep (PS)-suppressing effect of alpha-methyl-Dopa was studied in kittens at birth. The new burn animal received daily injections of alpha-methyl-Dopa during the 2 first weeks of life. States of sleep were studied during the treatment (days 1 to 14) and after administration of the drug way halted (days 15 and 16). Daily injections of alpha-methyl-Dopa induce an average PS-deprivation of 72%. This deprievation is compensated for by a significant increase in quiet sleep (QS)-rate which is found to be up to 3.5 times that of kittens not receiving alpha-methyl-Dopa. A progressive return of PS-ratio to normal, without PS rebound, is observed after drug administration ceases. Alpha-methyl-Dopa produces a sedative effect on the kitten which remains relatively hypotonic during the treatment. Behavioural studies carried out over the first month after birth show no significant delay in the ponderal growth nor in the acquisition of stereotyped behaviour patterns. However motor coordination is delayed 2 weeks in these kittens.