Urinary bladder function and somatic sensitivity in vasoactive intestinal polypeptide (VIP)-/- mice.
Vasoactive intestinal polypeptide (VIP) is an immunomodulatory neuropeptide widely distributed in neural pathways that regulate micturition. VIP is also an endogenous anti-inflammatory agent that has been suggested for the development of therapies for inflammatory disorders. In the present study, we examined urinary bladder function and hindpaw and pelvic sensitivity in VIP(-/-) and littermate wildtype (WT) controls. We demonstrated increased bladder mass and fewer but larger urine spots on filter paper in VIP(-/-) mice. Using cystometry in conscious, unrestrained mice, VIP(-/-) mice exhibited increased void volumes and shorter intercontraction intervals with continuous intravesical infusion of saline. No differences in transepithelial resistance or water permeability were demonstrated between VIP(-/-) and WT mice; however, an increase in urea permeability was demonstrated in VIP(-/-) mice. With the induction of bladder inflammation by acute administration of cyclophosphamide, an exaggerated or prolonged bladder hyperreflexia and hindpaw and pelvic sensitivity were demonstrated in VIP(-/-) mice. The changes in bladder hyperreflexia and somatic sensitivity in VIP(-/-) mice may reflect increased expression of neurotrophins and/or proinflammatory cytokines in the urinary bladder. Thus, these changes may further regulate the neural control of micturition.
Studeny
Simon
S
Department of Neurology, University of Vermont College of Medicine, D415A Given Research Building, Burlington, VT 05405, USA.
Cheppudira
Bopaiah P
BP
Meyers
Susan
S
Balestreire
Elena M
EM
Apodaca
Gerard
G
Birder
Lori A
LA
Braas
Karen M
KM
Waschek
James A
JA
May
Victor
V
Vizzard
Margaret A
MA
D000818:Animals; D003556:Cystitis / Q000139:chemically induced; D005260:Female; D006801:Humans; D006930:Hyperalgesia / Q000378:metabolism*; D051379:Mice; D018345:Mice, Knockout; D010147:Pain Measurement; D012021:Reflex, Abnormal / Q000502:physiology; D001743:Urinary Bladder / Q000502:physiology*; D014554:Urination / Q000502:physiology*; D014660:Vasoactive Intestinal Peptide / Q000235:genetics / Q000378:metabolism
D014660:Vasoactive Intestinal Peptide