Retia mirabilia: Protecting the cetacean brain from locomotion-generated blood pressure pulses.
Science
; 377(6613): 1452-1456, 2022 09 23.
Article
em En
| MEDLINE
| ID: mdl-36137023
ABSTRACT
Cetaceans have massive vascular plexuses (retia mirabilia) whose function is unknown. All cerebral blood flow passes through these retia, and we hypothesize that they protect cetacean brains from locomotion-generated pulsatile blood pressures. We propose that cetaceans have evolved a pulse-transfer mechanism that minimizes pulsatility in cerebral arterial-to-venous pressure differentials without dampening the pressure pulses themselves. We tested this hypothesis using a computational model based on morphology from 11 species and found that the large arterial capacitance in the retia, coupled with the small extravascular capacitance in the cranium and vertebral canal, could protect the cerebral vasculature from 97% of systemic pulsatility. Evolution of the retial complex in cetaceans-likely linked to the development of dorsoventral fluking-offers a distinctive solution to adverse locomotion-generated vascular pulsatility.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Pressão Sanguínea
/
Vasos Sanguíneos
/
Encéfalo
/
Circulação Cerebrovascular
/
Cetáceos
Limite:
Animals
Idioma:
En
Revista:
Science
Ano de publicação:
2022
Tipo de documento:
Article
País de afiliação:
Canadá