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Characterisation and comparison of temporal release profiles of nitric oxide generating donors.

Bradley SA, Steinert JR - J. Neurosci. Methods (2015)

Bottom Line: We found that donors such as NOC-5 and PAPA-NONOate decayed substantially within days, whereas SNP and GSNO showed greater stability releasing consistent levels of NO over days.In all donors tested, the amount of released NO differs between frozen and unfrozen stocks.Fluorescent and amperometric approaches to measure NO concentrations yield a wide range of levels.

View Article: PubMed Central - PubMed

Affiliation: MRC Toxicology Unit, Hodgkin Building, University of Leicester, Leicester LE1 9HN, UK.

No MeSH data available.


Related in: MedlinePlus

Temporal release of NO from SNP. (A) Representative example of the NO release profile from 200 μM SNP, demonstrating the application of the NO scavenger cPTIO (100 μM) at the end of all recordings to confirm microsensor specificity. Arrow depicts addition of cPTIO to recording solution. (B) Average release profile of NO from 100, 200 and 300 μM fresh SNP over a 30 min recording period. (C) Average profile of NO release over 30 min from two day old stock at 100, 200 and 300 μM. (D) Average release profiles of NO yield over 30 min from three day old SNP stock at 100, 200 and 300 μM. (E) Box and whisker plots showing the plateau concentration range of NO released from one day, two day and three day old stock at 100, 200 and 300 μM. (F) Box and whisker plots depicting the area under the curve for each recording using one day, two day and three day old SNP at 100, 200 and 300 μM.
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fig0010: Temporal release of NO from SNP. (A) Representative example of the NO release profile from 200 μM SNP, demonstrating the application of the NO scavenger cPTIO (100 μM) at the end of all recordings to confirm microsensor specificity. Arrow depicts addition of cPTIO to recording solution. (B) Average release profile of NO from 100, 200 and 300 μM fresh SNP over a 30 min recording period. (C) Average profile of NO release over 30 min from two day old stock at 100, 200 and 300 μM. (D) Average release profiles of NO yield over 30 min from three day old SNP stock at 100, 200 and 300 μM. (E) Box and whisker plots showing the plateau concentration range of NO released from one day, two day and three day old stock at 100, 200 and 300 μM. (F) Box and whisker plots depicting the area under the curve for each recording using one day, two day and three day old SNP at 100, 200 and 300 μM.

Mentions: The NO donor SNP is an iron nitrosyl compound that can be stored for years at room temperature if kept protected from light in a dry environment. To characterise the NO release from SNP we recorded NO levels over a period of three consecutive days from freshly made SNP stock. In order to establish that the response captured by the microsensor is specific to NO we added 100 μM of the NO scavenger cPTIO after each 30 min recording period. Addition of cPTIO resulted in an instant decrease in the response back to baseline indicative of a specific response to NO (Fig. 2A). Although cPTIO scavenging was conducted after every experiment to ensure accurate NO detection and measurement, it is not shown in all figures for simplicity. Addition of 100 μM SNP led to a steady rise followed by a plateau at ∼25 min (Fig. 2B). At 200 μM and 300 μM SNP the rise before the plateau is steeper with both plateauing at ∼25 min (Fig. 2B). Over a consecutive three day period, SNP stocks are remarkably stable if kept in the fridge and protected from light (Fig. 2C and D). Plateau concentrations of NO released from 100 μM SNP are 70 ± 6 nM on day one, 61 ± 11 nM on day two and 64 ± 6 nM on day three. 200 μM SNP results in NO release values of 130 ± 13 nM on day one, 124 ± 12 nM on day two and 127 ± 12 nM on day three. NO release from 300 μM SNP is 173 ± 14 nM day one, 178 ± 17 nM day two and 167 ± 15 nM day three (Fig. 2E, Table 1). To compare the total exposure of NO we calculated the area under the curve (AUC, Fig. 2F) which accounts for NO release as well as degradation which is particularly important for non-linear kinetics of the curve. The total amount of NO released over the 30 min recording period is consistent over the three consecutive days at all concentrations, demonstrating a high degree of stock stability over time.


Characterisation and comparison of temporal release profiles of nitric oxide generating donors.

Bradley SA, Steinert JR - J. Neurosci. Methods (2015)

Temporal release of NO from SNP. (A) Representative example of the NO release profile from 200 μM SNP, demonstrating the application of the NO scavenger cPTIO (100 μM) at the end of all recordings to confirm microsensor specificity. Arrow depicts addition of cPTIO to recording solution. (B) Average release profile of NO from 100, 200 and 300 μM fresh SNP over a 30 min recording period. (C) Average profile of NO release over 30 min from two day old stock at 100, 200 and 300 μM. (D) Average release profiles of NO yield over 30 min from three day old SNP stock at 100, 200 and 300 μM. (E) Box and whisker plots showing the plateau concentration range of NO released from one day, two day and three day old stock at 100, 200 and 300 μM. (F) Box and whisker plots depicting the area under the curve for each recording using one day, two day and three day old SNP at 100, 200 and 300 μM.
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Related In: Results  -  Collection

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fig0010: Temporal release of NO from SNP. (A) Representative example of the NO release profile from 200 μM SNP, demonstrating the application of the NO scavenger cPTIO (100 μM) at the end of all recordings to confirm microsensor specificity. Arrow depicts addition of cPTIO to recording solution. (B) Average release profile of NO from 100, 200 and 300 μM fresh SNP over a 30 min recording period. (C) Average profile of NO release over 30 min from two day old stock at 100, 200 and 300 μM. (D) Average release profiles of NO yield over 30 min from three day old SNP stock at 100, 200 and 300 μM. (E) Box and whisker plots showing the plateau concentration range of NO released from one day, two day and three day old stock at 100, 200 and 300 μM. (F) Box and whisker plots depicting the area under the curve for each recording using one day, two day and three day old SNP at 100, 200 and 300 μM.
Mentions: The NO donor SNP is an iron nitrosyl compound that can be stored for years at room temperature if kept protected from light in a dry environment. To characterise the NO release from SNP we recorded NO levels over a period of three consecutive days from freshly made SNP stock. In order to establish that the response captured by the microsensor is specific to NO we added 100 μM of the NO scavenger cPTIO after each 30 min recording period. Addition of cPTIO resulted in an instant decrease in the response back to baseline indicative of a specific response to NO (Fig. 2A). Although cPTIO scavenging was conducted after every experiment to ensure accurate NO detection and measurement, it is not shown in all figures for simplicity. Addition of 100 μM SNP led to a steady rise followed by a plateau at ∼25 min (Fig. 2B). At 200 μM and 300 μM SNP the rise before the plateau is steeper with both plateauing at ∼25 min (Fig. 2B). Over a consecutive three day period, SNP stocks are remarkably stable if kept in the fridge and protected from light (Fig. 2C and D). Plateau concentrations of NO released from 100 μM SNP are 70 ± 6 nM on day one, 61 ± 11 nM on day two and 64 ± 6 nM on day three. 200 μM SNP results in NO release values of 130 ± 13 nM on day one, 124 ± 12 nM on day two and 127 ± 12 nM on day three. NO release from 300 μM SNP is 173 ± 14 nM day one, 178 ± 17 nM day two and 167 ± 15 nM day three (Fig. 2E, Table 1). To compare the total exposure of NO we calculated the area under the curve (AUC, Fig. 2F) which accounts for NO release as well as degradation which is particularly important for non-linear kinetics of the curve. The total amount of NO released over the 30 min recording period is consistent over the three consecutive days at all concentrations, demonstrating a high degree of stock stability over time.

Bottom Line: We found that donors such as NOC-5 and PAPA-NONOate decayed substantially within days, whereas SNP and GSNO showed greater stability releasing consistent levels of NO over days.In all donors tested, the amount of released NO differs between frozen and unfrozen stocks.Fluorescent and amperometric approaches to measure NO concentrations yield a wide range of levels.

View Article: PubMed Central - PubMed

Affiliation: MRC Toxicology Unit, Hodgkin Building, University of Leicester, Leicester LE1 9HN, UK.

No MeSH data available.


Related in: MedlinePlus