Microcirculation, transport, continuous capillary, fenestrated capillary, discontinuous/sinusoidal capillary, factors affecting PO2

3 Pages
125 Views
Unlock Document

Department
Biomedical Science
Course
BMS 420
Professor
Charles Miller
Semester
Fall

Description
10 September Vasomotion – waxing and waning of tone of upstream vascular smooth muscle cells Anatomy of the Microcirculation Density of capillaries (vascularization) obviously important for exchange – lung has capillary area of 3,500 cm /g while muscle is about 100 cm /g; tendon – low density Degree of patency varies – 100% heart to 20 – 30% in skeletal muscle and intestines at rest Pericapillary sphincters controlled by local factors Vascular Bed Arterioles: 5 – 25 μm; continuous VSM; innervated (sympathetic); controls capillary Q Metarterioles: discontinuous VSM; short Precapillary sphincter: single band of VSM; usually not innervated; controls capillary Q True capillaries: 2 -5 μm; primarily endothelial cells; thin walled (200 – 300 nm); not innervated Exchange Occurs primarily in capillaries but also in metarterioles (oxygen) and venules (protein) Types of capillaries Continuous Fenestrated – largish pores between cells (kidney, e.g.) Discontinuous Pinocytotic vesicles allow higher weight molecules to move out of blood 4 types of transport: diffusion, bulk flow, vesicular transport, active transport Shared Characteristics Single layer of endothelial cells (.2 μm thick) Clefts or slits at junction of cells Basement membrane beneath EC cells Micro-pinocytotic vessels Continuous Capillary
More Less

Related notes for BMS 420

Log In


OR

Join OneClass

Access over 10 million pages of study
documents for 1.3 million courses.

Sign up

Join to view


OR

By registering, I agree to the Terms and Privacy Policies
Already have an account?
Just a few more details

So we can recommend you notes for your school.

Reset Password

Please enter below the email address you registered with and we will send you a link to reset your password.

Add your courses

Get notes from the top students in your class.


Submit