Biomaterial Database

Microsphere size and determination of intrarenal blood flow distribution in the rat. 1979

A Mimran, and D Casellas

The influence of microsphere size upon the estimation of cardiac output (CO), renal blood flow (RBF) and its cortical distribution (ICBFD) was evaluated by simultaneous injection of 8.5 +/- 0.8 micrometer (SD) and 12.7 +/- 1.7 micrometer (SD) spheres in control conditions and after hemorrhagic hypotension (HH rats). The values of CO and RBF were unaffected whilst the ratio of flow to outer and inner halves of cortex (OCF/ICF) was 32% higher with 12.7 micrometer than with 8.5 micrometer spheres in both groups. Microscopic analysis of cleared kidneys slices confirmed that large spheres were more concentrated in outermost and less concentrated in innermost glomeruli than small spheres. In addition, the ratio of sphere number per outermost to that per innermost glomerulus (fs/fjm), and approximation of glomerular blood flow distribution was 1.74 and 1.76 with large spheres and 0.98 and 1.06 with small spheres in control and HH rats respectively. It is concluded that the artifact due to sphere size was not minimized in low flow conditions (HH rats) and that 8.5 micrometer spheres may be a more realistic marker of glomerular blood flow distribution in the rat than 12.7 micrometer spheres.

UI	MeSH Term	Description	Entries
D007022	Hypotension	Abnormally low BLOOD PRESSURE that can result in inadequate blood flow to the brain and other vital organs. Common symptom is DIZZINESS but greater negative impacts on the body occur when there is prolonged depravation of oxygen and nutrients.	Blood Pressure, Low,Hypotension, Vascular,Low Blood Pressure,Vascular Hypotension
D007668	Kidney	Body organ that filters blood for the secretion of URINE and that regulates ion concentrations.	Kidneys
D008297	Male		Males
D008863	Microspheres	Small uniformly-sized spherical particles, of micrometer dimensions, frequently labeled with radioisotopes or various reagents acting as tags or markers.	Latex Beads,Latex Particles,Latex Spheres,Microbeads,Bead, Latex,Beads, Latex,Latex Bead,Latex Particle,Latex Sphere,Microbead,Microsphere,Particle, Latex,Particles, Latex,Sphere, Latex,Spheres, Latex
D012039	Regional Blood Flow	The flow of BLOOD through or around an organ or region of the body.	Blood Flow, Regional,Blood Flows, Regional,Flow, Regional Blood,Flows, Regional Blood,Regional Blood Flows
D001794	Blood Pressure	PRESSURE of the BLOOD on the ARTERIES and other BLOOD VESSELS.	Systolic Pressure,Diastolic Pressure,Pulse Pressure,Pressure, Blood,Pressure, Diastolic,Pressure, Pulse,Pressure, Systolic,Pressures, Systolic
D002302	Cardiac Output	The volume of BLOOD passing through the HEART per unit of time. It is usually expressed as liters (volume) per minute so as not to be confused with STROKE VOLUME (volume per beat).	Cardiac Outputs,Output, Cardiac,Outputs, Cardiac
D006470	Hemorrhage	Bleeding or escape of blood from a vessel.	Bleeding,Hemorrhages
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D051381	Rats	The common name for the genus Rattus.	Rattus,Rats, Laboratory,Rats, Norway,Rattus norvegicus,Laboratory Rat,Laboratory Rats,Norway Rat,Norway Rats,Rat,Rat, Laboratory,Rat, Norway,norvegicus, Rattus