Urinary levels of substance P and its metabolites are not increased in interstitial cystitis.
OBJECTIVE
To determine whether interstitial cystitis is associated with the increased release of substance P from the bladder wall into urine, by measuring urinary excretion rates of substance P and its metabolites in women with interstitial cystitis and in a control group of women with stress incontinence and normal bladder function.


METHODS
Catheter urine was collected from 13 patients and 10 controls during a water diuresis ( approximately 10 mL/min) before and after instilling the bladder with 100 mL of water. The contribution of the bladder wall to urinary substance P peptides was assessed by measuring the change in substance P peptide levels after 2 min of bladder stasis before and after instillation.


RESULTS
Absolute substance P excretion rates were similar in patients with interstitial cystitis and controls; 2 min of bladder stasis reduced the substance P excretion rate (P = 0.03) and increased the excretion rate of substance P metabolites (P = 0.01).


CONCLUSIONS
The release of substance P from the bladder wall was not increased in patients with interstitial cystitis.
Campbell
D J
DJ
St. Vincent's Institute of Medical Research, Fitzroy, Victoria, Australia. j.campbell@medicine.unimelb.edu.au
Tenis
N
N
Rosamilia
A
A
Clements
J A
JA
Dwyer
P L
PL
D002851:Chromatography, High Pressure Liquid / Q000379:methods; D018856:Cystitis, Interstitial / Q000652:urine*; D005260:Female; D006801:Humans; D013373:Substance P / Q000652:urine*
D013373:Substance P