Electrocardiac responses associated with the fear paralysis reflex in infant rabbits and rats. Relation to sudden infant death.
It is a controversial issue whether non-hereditary prolonged cardiac repolarization (increased QT-interval in ECG) is a cause of sudden infant death syndrome (SIDS). The QT-interval has, however, been found to be normal at rest. The present experiments on infant rats and infant and adult rabbits demonstrate a transient QT-prolongation during the innate fear paralysis reflex elicited by a variety of frightening stimuli. This reflex has previously been proposed as a triggering mechanism for SIDS. It may represent an extrinsic cause of QT-prolongation which adds to an intrinsic defect in repolarization previously reported. The present findings lend further support to the fear paralysis theory of SIDS.
Kaada
B
B
Rogaland Central Hospital, Stavanger, Norway.
D000818:Animals; D000831:Animals, Newborn / Q000502:physiology*; D001919:Bradycardia / Q000503:physiopathology*; D005239:Fear; D011817:Rabbits; D051381:Rats; D011919:Rats, Inbred Strains; D013216:Reflex, Startle / Q000502:physiology*