Ontogeny of heart rate response to milk infusion in infant rats as a function of level of deprivation.
The heart rate (HR) responses of infant rats aged 8, 11, 14, and 17 days were recorded during the intraoral infusion of milk. Subjects were deprived for various periods of time prior to the start of testing. The results revealed a transition from HR deceleration to HR acceleration between 8 and 14 days of age, with the magnitude of the response varying directly with the degree of deprivation. A follow-up experiment was run in order to demonstrate that the observed HR changes were not a result of the termination of infusion. Implications for a transition from infant to adult feeding systems as well as the development of a somatic-cardiac linkage are discussed.
D000375:Aging; D000818:Animals; D001070:Appetitive Behavior; D001143:Arousal; D003216:Conditioning, Operant; D006339:Heart Rate; D006815:Hunger; D051381:Rats; D011919:Rats, Inbred Strains