J 2020

Conditioned Variation in Heart Rate During Static Breath-Holds in the Bottlenose Dolphin (Tursiops truncatus)

FAHLMAN, Andreas, Bruno COZZI, Mercy MANLEY, Sandra JABAS, Marek MALÍK et. al.

Basic information

Original name

Conditioned Variation in Heart Rate During Static Breath-Holds in the Bottlenose Dolphin (Tursiops truncatus)

Authors

FAHLMAN, Andreas (guarantor), Bruno COZZI, Mercy MANLEY, Sandra JABAS, Marek MALÍK (203 Czech Republic, belonging to the institution), Ashley BLAWAS and Vincent M. JANIK

Edition

Frontiers in Physiology, Lausanne, Frontiers, 2020, 1664-042X

Other information

Language

English

Type of outcome

Článek v odborném periodiku

Field of Study

30105 Physiology

Country of publisher

Switzerland

Confidentiality degree

není předmětem státního či obchodního tajemství

References:

Impact factor

Impact factor: 4.566

RIV identification code

RIV/00216224:14110/20:00117278

Organization unit

Faculty of Medicine

DOI

UT WoS

000596357800001

Keywords in English

dive response; diving physiology; marine mammal; reflex; cardiovascular physiology; selective gas exchange hypothesis; adaptation; cardiovascular function

Tags

Tags

International impact, Reviewed
Změněno: 5/1/2021 08:57, Mgr. Tereza Miškechová

Abstract

V originále

Previous reports suggested the existence of direct somatic motor control over heart rate (f(H)) responses during diving in some marine mammals, as the result of a cognitive and/or learning process rather than being a reflexive response. This would be beneficial for O-2 storage management, but would also allow ventilation-perfusion matching for selective gas exchange, where O-2 and CO2 can be exchanged with minimal exchange of N-2. Such a mechanism explains how air breathing marine vertebrates avoid diving related gas bubble formation during repeated dives, and how stress could interrupt this mechanism and cause excessive N-2 exchange. To investigate the conditioned response, we measured the f(H)-response before and during static breath-holds in three bottlenose dolphins (Tursiops truncatus) when shown a visual symbol to perform either a long (LONG) or short (SHORT) breath-hold, or during a spontaneous breath-hold without a symbol (NS). The average f(H) (if(Hstart)), and the rate of change in f(H) (dif(H)/dt) during the first 20 s of the breath-hold differed between breath-hold types. In addition, the minimum instantaneous f(H) (if(Hmin)), and the average instantaneous f(H) during the last 10 s (if(Hend)) also differed between breath-hold types. The dif(H)/dt was greater, and the if(Hstart), if(Hmin), and if(Hend) were lower during a LONG as compared with either a SHORT, or an NS breath-hold (P < 0.05). Even though the NS breath-hold dives were longer in duration as compared with SHORT breath-hold dives, the dif(H)/dt was greater and the if(Hstart), if(Hmin), and if(Hend) were lower during the latter (P < 0.05). In addition, when the dolphin determined the breath-hold duration (NS), the f(H) was more variable within and between individuals and trials, suggesting a conditioned capacity to adjust the f(H)-response. These results suggest that dolphins have the capacity to selectively alter the f(H)-response during diving and provide evidence for significant cardiovascular plasticity in dolphins.