Table 2.
Tissue concentrationsa (pM) of [125I]-IgG following intranasal or intra-arterial administration (middle dose).
| Intranasal dose (1 mg) | Intra-arterial dose (2.6 μg) | |
|---|---|---|
| Blood | (pM) | (pM) |
| 0 min | 0 (6) | 1465.05 ± 87.27 (6) |
| 10 min | 239.61 ± 55.69 (6) | 1086.02 ± 94.06 (6) |
| 20 min | 724.60 ± 171.93 (6) | 975.01 ± 89.29 (6) |
| 30 min | 1150.97 ± 194.40 (6) | 917.77 ± 85.04 (6) |
| Blood AUC (0–30 min) | (pM*min) | (pM*min) |
| 15,396.90 ± 3216.89 (6) | 32,524.37 ± 2497.53 (6) | |
| Nervous system regions | (pM) | (pM) |
| ACA & MCA b | 1280 ± 461.5 (6) d | 4.02 ± 1.03 (6) |
| Basilar & vertebral arteries c | 1177.49 ± 382.34 (5) e | 2.77 ± 1.26 (6) |
| Olfactory bulbs | 720.77 ± 246.14 (6) d | 0.53 ± 0.10 (6) |
| Frontal cortex | 154.62 ± 47.67 (6) d | 0.34 ± 0.10 (6) |
| Caudoputamen | 133.82 ± 58.28 (6) d | 1.49 ± 0.71(6) |
| Motor cortex | 135.76 ± 50.03 (6) d | 0.47 ± 0.07 (6) |
| Primary somatosensory cortex | 209.42 ± 21.47 (5) e | 0.54 ± 0.18 (6) |
| Midbrain | 38.53 ± 9.38 (6) d | 0.34 ± 0.50 (6) |
| Posterior hippocampus | 45.44 ± 8.14 (6) d | 0.33 ± 0.06 (6) |
| Medulla | 107.42 ± 30.58 (6) d | 0.26 ± 0.06 (6) |
| Pons | 55.60 ± 14.99 (6) d | 0.34 ± 0.06 (6) |
| Cerebellum | 40.39 ± 9.80 (6) d | 0.56 ± 0.20 (6) |
| Cervical spinal cord | 334.35 ± 224.67 (6) d | 0.25 ± 0.13 (6) |
| Trigeminal nerves | 1706.60 ± 779.57 (4) f | 3.66 ± 1.13 (6) |
| Lymph nodes | (pM) | (pM) |
| Deep cervical lymph nodes | 3020.64 ± 1432.84 (5) e | 16.02 ± 5.05 (6) |
| Superficial cervical lymph nodes | 2108.56 ± 934.36 (6) d | 9.86 ± 0.58 (6) |
| Axillary lymph nodes | 202.98 ± 42.48 (6) d | 8.87 ± 0.57 (6) |
Blood, nervous system, and lymph node radiolabel concentrations following intranasal or intra-arterial administration of [125I]-IgG (middle doses). Intranasal administration of a middle (20-fold higher than tracer) dose (1 mg) was performed drop wise (4 drops of 12 μl each) over approximately 15 min. Intra-arterial administration of a dose (2.6 μg) that resulted in similar end point blood concentrations as the intranasal dose was performed as a bolus dose (500 μl) over 1–2 min. The concentration at time zero following intra-arterial administration of [125I]-IgG was estimated by extrapolation.
Data are presented as mean ± S.E.M. (n independent experiments);
anterior cerebral and middle cerebral arteries – isolated perfused vessels (indirect measure of perivascular compartment);
isolated perfused posterior circulation vessels mainly comprising the basilar and vertebral arteries (a small portion of the proximal posterior cerebral and superior cerebellar arteries are also included; indirect measure of perivascular compartment); Statistical analysis for tissue samples - intranasal vs intra-arterial dosing: Mann-Whitney Rank sum test –
Mann-Whitney U = 0, p = .002;
Mann-Whitney U = 0, p = .004;
Mann-Whitney U = 0, p = .010.