The intracellular calcium chelator BAPTA decreased cell retention of I-HIV at 20 uM (panel A) and increased transport rate of I-HIV at 10 uM (panel B).

<p>This is consistent with an increased rate of transport across the BMEC. The calcium channel blocker verapamil had no affect on transport. The calcium ionophore A23187 increased I-HIV permeability (panel C) and decreased TEER (panel D) in BMEC.</p

Panel A shows kinetics of uptake of radioactively labeled HIV-1 (I-HIV) over time by BMEC.

<p>Panels B and C show linearity with increases concentrations of I-HIV. Temperature decreased permeation of I-HIV (panel D) and of I-Albumin (panel E) in BMEC.</p

Panel A: Cleavage of high mannose oligosaccharides from HIV with endoglycosidase F1 (eF1) reduced the transport of I-HIV across BMEC.

<p>Panel B: The internal control of I-Albumin was unaffected. Mannose-6 phosphate, a ligand for and competitive inhibitor of the mannose-6 phosphate receptor, inhibited the uptake (panel C) and permeation (panel D) of I-HIV across BMECs.</p

Panels A and B: HIV particles (arrows) in the lumen (panel A) and in an endothelial cell (panel B) of blood vessels in mouse cerebral cortex.

<p>The boxed regions show higher magnification images. Panel C: HIV (arrows) have traversed the endothelium of a blood vessel in mouse brain cerebral cortex and gained access the perivascular space. Panels D–F: Colloidal gold labeled HIV in the lumen (arrowhead in panel E, and panel F) and in endothelial cells (arrows in panels D and E) of mouse cerebral cortex capillaries. Panels G and H: HIV associated with myelin sheaths (arrows) of nerve axons in mouse cerebral cortex. Thin sections were incubated with HIV-1SF2 gp120 antiserum diluted 1:100 and followed, after washing, by incubation in protein A-10 nm gold diluted 1∶100. B – brain parenchyma, E – endothelium, L – capillary lumen, RBC – red blood cell.</p

Uptake (panels A and B) and transport (panels C and D) were inhibited by mannose (panels A and C) and by mannan (panels B and D).

<p>Uptake (panels A and B) and transport (panels C and D) were inhibited by mannose (panels A and C) and by mannan (panels B and D).</p

Mannan blocked the increase in I-HIV uptake induced by WGA (panel A) and by protamine (panel B) in BMEC cells.

<p>Neither WGA nor WGA + mannan had an effect on I-Albumin uptake (panel C). Protamine increased uptake of I-Albumin by BMEC although much less robustly than the uptake of I-HIV; mannan blocked this effect, although at higher doses than for the protamine/HIV-1 effect (panel D).</p

Expression of M6P receptor on nonpermeablized primary monolayer cultures of mouse brain endothelial cells.

<p>Receptor was detected on cells not treated with epinephrine and treatment did not enhance intensity of staining.</p

Blood-brain barrier disruption and brain pharmacokinetics of PGUS at two doses of epinephrine.

<p>(A) shows that the 120 nmol/mouse dose of epinephrine decreased the vascular space of I-Alb. (B) shows that neither dose disrupted the BBB. (C) shows that both doses reduced vascular space of I-PGUS and that the 120 nmol/mouse dose also slowed clearance from blood. (D) shows that I-PGUS did not cross the BBB, but that both doses of epinephrine induced transport of I-PGUS across the BBB. n = 7/group.</p

Effect of adrenergic antagonists on epinephrine-induced uptake of I-PGUS across the BBB.

<p>Upper panel shows that more general alpha, alpha1, and alpha2 antagonists but not beta antagonists blocked epinephrine’s effect. Lower panel shows results that the highly selective alpha1 adrenergic receptor antagonist benoxathian but not the highly selective beta adrenergic receptor antagonist CPG20712A blocked the effect of epinephrine. **p<0.01 and ***p<0.001 inc comparison to control; ##p<0.01 and ###p<0.001 in comparison to epinephrine.</p

Effect of monoamines and acetylcholine on I-PGUS uptake.

<p><b>Only epinephrine enhanced BBB penetration.</b> **P<0.01; n = 7-10/group.</p