Ultrastructure Of The Human Dermal Microcirculation: The Horizontal Plexus Of The Papillary Dermis

Agnes Yen, Irwin M. Braverman
1976 Journal of Investigative Dermatology  
Electron mi croscopy was used to define the ultrastructul't? lit' t ill:: ' ' a ri ous segments of the human cutaneous microcirculati on in normal forearm s kin . The organiza t.ion of the ,'essels in the horizontal plexus of the papilla ry dermis was reconstructed from l·,um plasticembedded sections. Ultrathin sections were taken at 10-to 20-,um intervals over a distance of 450 ~m . Arterioles were followed throu~h the capilla ry bed to their venous co nnections. Terminal art.erioles. arterial
more » ... and venous capi llaries. and postcapillary venules were identifi ed on the basis of size. cellula r co mpos it ion of their walls. and their rel ationship to the other segments of the microvascula r bed . The arterial segments were characterized by a homogeneous basement membrane and the venous segments by a multilaminated basement membrane. The elastic lamina in the a rterioles was a disco ntinuous layer which gradually disappeared from the art eri ola r wall to form an ext.ern al sheath just before the arteriole con nected with the arterial capillary segmen t. The vascular wall s va ried fro m 1 to 5 ,urn in all of the segments of the microvascular bed . Criteria are proposed for identif .... ing the various segments of the microcirculation so that their roles in dermatoses and vascular malformat ions can be evaiuated.
doi:10.1111/1523-1747.ep12481678 pmid:1249441 fatcat:4cgchebpybdwdkwhmgm2xoyrzm