A Immuno-Histochemical Study on the Influences of Various Humoral Factors to Serum Lipoprotein Entry into Arterial Wall

Abstract

In order to investigate the entry of serum lipoprotein into the arterial wall and influence of various humoral factors such as renin, norepinephrine, epinephrine and angiotensin-II to the lipoprotein entry, immuno-fluorescient antibody method has been utilized to identify tissue antigens of serum lipoprotein in the rabbit thoracic aorta. Two procedures have been employed.
In the in vitro study, the humoral factors were added into incubation medium directly in which the arterial wall incubated with LDL. In the in vivo study, the humoral factors were injected into the rabbit vein with a continious infusion pump for 6 hours. Then, the thoracic aorta was obtained as a material.
Results and conclusions were follows.
1) In both in vitro and in vivo studies, no immuno-fluorescience of the LDL has been observed at the additions of renin, norepinephrine and epinephrine.
2) Immuno-fluorescience of LDL has been observed when angiotensin-II was administered intermittently at intervals of 15min. in vitro, and injected cotiniously in vivo.
3) In the in vitro study, immuno-fluorescience of the incubated LDL was observed inside of endothelium and not identified in the other dimensions which exope to the LDL directly.
4) From the above mentioned results, it may be concluded that endotherial cells play important role to uptake the LDL into the arterial wall and angiotensin-II is one of the most important factors which affect the lipoprotein uptake.