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Gene & Protein in Disease Diagnosis and treatment of aldosterone-related diseases

Therefore, to improve the accuracy of PA screening, new 3.3. Liquid chromatography tandem mass
diagnostic methods need to be explored. spectrometry
3.1. Radioimmunoassay RIA and CLIA are two commonly used methods based
on immune technology in China. However, they are
At present, radioimmunoassay (RIA) is used to detect prone to cross-reactions with other steroid hormones
plasma aldosterone concentration (PAC) and plasma renin or metabolites, resulting in false positives or false
activity (PRA). PRA is reflected by measuring the rate of negatives [31,32] . Liquid chromatography tandem mass
conversion of angiotensinogen to angiotensin I (Ang I) per spectrometry (LC-MS/MS) is a detection method
unit time. However, its downside is that it cannot directly that combines chromatographic separation and mass
reflect the active concentration of renin . RIA detection of spectrometry analysis. LC-MS/MS is predominantly used
[28]
PAC is based on the principle of homogeneous competition, for small molecule detection and newborn screening,
in which the content of aldosterone in samples is detected prenatal care, etc. Having several advantages, including
by radioiodine labeling . RIA is one of the commonly high sensitivity, high specificity, and high throughput,
[29]
used methods for clinical testing internationally. Although LC-MS/MS is taking the lead in the detection field .
[33]
RIA has an ideal and mature technical process, it has However, this technology uses liquid-liquid extraction,
several limitations: (1) Its detection of PRA is affected which takes a long time for chromatographic analysis and
by the activity of renin itself and the interaction with its requires a substantial amount of samples to address the
own substrate, which reduces the repeatability of the issue of sensitivity. In addition to its high requirements for
experimental results; additionally, its performance is the laboratory environment and operators, its equipment
poor, and the detection differences between each product cost is also high. Therefore, it has not been widely used in
are inconsistent; (2) plasma aldosterone and plasma local clinical practice. In the screening of PA, although the
renin activities are detected separately, and its operation RIA method has several disadvantages, it is still one of the
process is cumbersome and time-consuming; and (3) it commonly used methods due to its mature technology and
has certain radioactivity, with higher requirements for the
experimental environment and experimental operators . high consistency with CLIA results. LC-MS/MS, as a novel
[27]
approach in the detection field, has not gained sufficient
3.2. Chemiluminescence immunoassay (CLIA) market recognition in China. Therefore, hospitals and
laboratories have not conducted enough research to collect
Although RIA is commonly used in China, the sensitivity clinical data, thus making it impossible to establish a
of renin detection cannot be overlooked. Hence, the definitive correlation with RIA and CLIA in the detection
novel active/direct renin concentration (ARC/DRC) of ARR and other methods . While promoting LC-MS/
[31]
measurement method has become a new trend. CLIA is MS, it would be beneficial to compare the detection
an emerging method that enables automated simultaneous performance of immunoassay and mass spectrometry
measurement of renin and aldosterone concentrations . through experimental data, determine the correlation and
[30]
CLIA is a method often used in biochemical immunoassays, difference, as well as identify the best entry point between
usually by means of using chemiluminescence reagents them, so as to improve the diagnostic accuracy .
[34]
that label antigens or antibodies and react with antibodies
or antigens coated on the sample/magnetic particles. 4. Drugs related to the treatment of
The antigen or antibody, which is bound or separated, aldosterone-related diseases
will be labeled with the luminescent agent in its free
state to evaluate the content of the target quantitatively Aldosterone is a mineralocorticoid secreted by the adrenal
or qualitatively in the sample to be tested [27-29] . CLIA can cortex, and it is the last active substance of the RAAS.
directly measure plasma renin concentration. Studies have Aldosterone is named as such due to the oxidation of
successively proven that the effect of using this method methyl by cholesterol to an aldehyde group at position C18
for screening PA is not only equivalent to that of the RIA following a series of enzymatic reactions [2,3] . Aldosterone
method, but that it can also overcome the shortcomings of promotes potassium excretion and sodium reabsorption in
RIA. Therefore, in 2008, this method was included in the the distal convoluted tubules and cortical collecting ducts,
European Endocrine Society Clinical Practice Guidelines. and it is a key hormone that regulates sodium-potassium
However, since most of the fully automatic equipment balance and maintains homeostasis in the body. A large
used in China is imported, it requires imported reagents. number of data have proven that aldosterone is related
Considering the cost and the equipment itself, this method to various target organ damage diseases, which can be
has yet to be widely employed in clinical practice in effectively treated by inhibiting the excessive activation
China . of aldosterone on the MR. Studies have shown that MR
[24]

Volume 1 Issue 2 (2022) 4 https://doi.org/10.36922/gpd.v1i2.136