Review for 10.1186/1471-230X-4-16 (2004)

Reviewer's report 
 Nitric oxide-an endogenous inhibitor of gastric acid secretion in isolated human gastric glands Title: 
 1  18 February 2004 Version: Date: 
 Lars Fandriks Reviewer: 
Reviewer's report: 
General 
The authors report that NO acts inhibitory on acid secretion in isolated human gastric glands. The 
method used is well-esatblished and experimental procedures are skillfully performed. However, the 
number of experiments are generally low and no statistical analysis is presented. It follows that I am 
very concerned about the statistical robustness of the reported data in relation to the conclusions 
drawn. 
------------------------------------------------------------------------------- Major Compulsory Revisions (that the author must respond to before a decision on publication can be reached) 
Statistical significance of stated effects are not analysed. For example, in Results L-arg is stated to 
decrease the AP ratio but when consulting Fig 2a the effect is not obvious, at least not in comparison to SNP. Furthermore, fig 2b shows convincingly that administration of the NOS-inhibitor L-NAME was 
associated with increased AP ratio indicating an inhibitory action by NO. No effect was obtained in 
presence of D-NAME. However, only two such D-NAME experiments were performed. At least a doubling of the number of these experiments has to be done in order to convince me that the isomer 
was without effect. If this is the case, such a stereospecificity will strengthen strongly the assumption 
that NOS mediated NO formation inhibits the acid secretion in this preparation. Also the db-cAMP 
experiments are very few (n=2 or 3) thus being a weak basis for the conclusions. 
Although the paper is mainly confirmative some more experiments are needed together with a 
proper statistical analysis before it could be considered for publication. 
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Minor Essential Revisions (such as missing labels on figures, or the wrong use of a term, which the author can be trusted to correct) 
1. Background: The references to NO mediated influence on duodenal and gastric bicarbonate 
secretions (ref 9, 10, 11) are not entirely correct. Please revise. 
2. All secretory data are given as % of maximal secretion in response to histamine or db-cAMP as 
calculated separately for each individual. Please state in text if this calculation was based on single 
analysis or duplicate, triplicates ? 
3. Immunohistochemistry: 
Please state in how many of the individuals this analysis was performed and that preparation in 
absence of the primary antibody was unstained. . Other isoforms of NOS were not analysed; Please include in Discussion the reasons. 
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Discretionary Revisions (which the author can choose to ignore) 
 Unable to decide on acceptance or rejection until the authors have responded to the What next?: 
major compulsory revisions 
 An article whose findings are important to those with closely related research Level of interest: 
interests 
 Acceptable Quality of written English: 
 Yes Statistical review: 
Declaration of competing interests: 
None