Time-Course Evaluation of 2,3-Diphosphoglycerate Levels in Canine Packed Red Blood Cells Stored in Two Different Additive Solutions
Introduction
The 2,3-diphosphoglycerate (2,3-DPG) is an allosteric modulator of hemoglobin which facilitates the release of oxygen to tissues. Depletion of 2,3 DPG during RBCs storage is associated with a decreased release of oxygen from the transfused RBCs. Previous studies demonstrated benefits of using additive solutions in order to improve maintenance of 2,3-DPG in human RBCs during storage.
Objectives
To evaluate the changes of 2,3-DPG levels in canine RBCs stored in two different additive solutions including SAGM and AS-3.
Methods
Six healthy dogs were included in this study. A unit of whole blood-derived pRBC was prepared from each dog and divided equally into three portions. The first portion was resuspended with SAGM (SAGM group), the second portion was resuspended with AS-3 (AS-3 group), and the third portion was not resuspended with additive solution (control group). The characteristics of SAGM and AS-3 are shown in Table 1.
All pRBC groups were stored in 4°C and samples were obtained at day 1, 14, 21, 28, 35, and 42 of storage. The 2,3-DPG levels from each sample were determined by enzymatic assay kit.
Table 1. Composition and characteristic of SAGM and AS-3 additive solutions used in this study
|
SAGM*
|
AS-3**
|
Each 100 mL contains
|
|
|
Adenine (g)
|
0.0169
|
0.030
|
Dextrose (g)
|
0.900
|
1.000
|
Mannitol (g)
|
0.525
|
-
|
Sodium Chloride (g)
|
0.877
|
0.410
|
Monobasic Sodium Phosphate (Monohydrate) (g)
|
-
|
0.276
|
Sodium Citrate (Dihydrate) (g)
|
-
|
0.588
|
Citric acid (Monohydrate) (g)
|
-
|
0.042
|
pH
|
6.2
|
5.8
|
Osmolarity (mOsm/kg)
|
376
|
291
|
*SAGM - saline-adenine-glucose-mannitol additive solution
**AS-3 - additive solution formula no. 3
Results
The 2,3-DPG levels were significantly decreased (p<0.001) overtime in all groups (Table 2). The overall 2,3-DPG decline rates were significantly slower in SAGM and AS-3 groups compared to control (p<0.05). There were no significant differences in the 2,3-DPG levels and decline rates between SAGM and AS-3 groups (Figure 1).
Table 2. Level of 2,3-DPG in canine pRBC from different groups determined on different days of storage*
|
SAGM
|
AS-3 group
|
Control group
|
2,3-DPG (µmol/g Hb)
|
|
|
|
Day 1
|
18.117 (0.53)
|
17.250 (0.59)
|
15.833 (0.58)
|
Day 14
|
15.450 (0.41)
|
15.817 (0.33)
|
10.133 (0.63)
|
Day 21
|
12.583 (0.48)
|
12.150 (0.38)
|
5.617 (0.38)
|
Day 28
|
9.817(0.38)
|
9.800 (0.34)
|
3.933 (0.18)
|
Day 35
|
8.633 (0.34)
|
9.200 (0.40)
|
3.60 (0.48)
|
Day 42
|
5.183 (0.59)
|
5.333 (0.69)
|
2.317 (0.18)
|
*Data shown represents mean ± SD (n=6)
Figure 1 | Level of 2,3-DPG levels in canine pRBC from SAGM group (□) AS-3 group (○) and control group (Δ) during storage. Results shown represent mean±SD (n=6). |
|
| |
Conclusions
These results indicate that SAGM and AS-3 additive solutions provide better maintenance of 2,3-DPG levels in canine pRBCs during storage.