Blood pressure and heart rate during tonic immobility in the black tipped reef shark,Carcharhinus melanoptera

P S Davie; C E Franklin; G C Grigg

doi:10.1007/BF00004374

Blood pressure and heart rate during tonic immobility in the black tipped reef shark,Carcharhinus melanoptera

Fish Physiol Biochem. 1993 Aug;12(2):95-100. doi: 10.1007/BF00004374.

Authors

P S Davie¹, C E Franklin, G C Grigg

Affiliation

¹ Heron Island Research Station, The University of Queensland, Heron Island, The Great Barrier Reef, Queensland, Australia.

PMID: 24202688
DOI: 10.1007/BF00004374

Abstract

Tonic immobility was induced in black tipped reef sharks (Carcharhinus melanoptera) and heart rate and ventral aortic blood pressure recorded. Without branchial irrigation, tonic immobility was correlated with a significant depression in blood pressure and heart rate irrespective of the sharks being in air or in water. Tonic immobility with branchial irrigation resulted in a significant increase in blood pressure in sharks in air, but not in water. Heart rate was unchanged when the gills were irrigated. Intra-arterial injections of atropine abolished the bradycardia and blood pressure rise associated with tonic immobility. We conclude that, during tonic immobility, sharks are able to receive afferent information from the ventilatory system and make appropriate responses via the vagus nerve.