Whole-body systemic transcapillary filtration rates, coefficients, and isogravimetric capillary pressures in Bufo marinus and Rana catesbeiana. Physiol Biochem Zool 2000;73(2):161-8
Date
05/10/2000Pubmed ID
10801394DOI
10.1086/316732Scopus ID
2-s2.0-0034044216 (requires institutional sign-in at Scopus site) 18 CitationsAbstract
Whole-body and organ-level transcapillary filtration rates and coefficients are virtually unexamined in ectothermal vertebrates. These filtration rates appear to be greater than in mammals when plasma volume shifts and lymphatic function are analyzed. Gravimetric techniques monitoring whole-body mass changes were used to estimate net systemic filtration in Bufo marinus and Rana catesbeiana while perfusing with low-protein Ringer's and manipulating venous pressure. Capillary pressures were estimated from arterial and venous pressures after measuring the venous to arterial resistance ratio of 0.23. The capillary filtration coefficient (CFC) for the two species was 25.2+/-1.47 mL min-1 kg-1 kPa-1. Isogravimetric capillary pressure (Pci), the pressure at which net fluid is neither filtered nor reabsorbed, was 1.12+/-0.054 kPa and was confirmed by an independent method. None of these variables showed a significant interspecific difference. The anuran CFC and Pci are significantly higher than those found using the same method on rats (7.6+/-2.04 mL min-1 kg-1 kPa-1 and 0.3+/-0.37 kPa, respectively) and those commonly reported in mammals. Despite the high CFC, the high Pci predicts that little net filtration will occur at resting in vivo capillary pressures.
Author List
Hancock TV, Hoagland TM, Hillman SSMESH terms used to index this publication - Major topics in bold
AnimalsBlood Pressure
Bufo marinus
Capillaries
Capillary Permeability
Epinephrine
Female
Histamine
Isotonic Solutions
Male
Perfusion
Rana catesbeiana
Rats
Rats, Sprague-Dawley
Serum Albumin, Bovine
Transducers
Vasoconstrictor Agents
