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.
Department of Neurology, University of Vermont College of Medicine, D415A Given Research Building, Burlington, VT 05405, USA.
Simon
S
Studeny
Bopaiah P
BP
Cheppudira
Susan
S
Meyers
Elena M
EM
Balestreire
Gerard
G
Apodaca
Lori A
LA
Birder
Karen M
KM
Braas
James A
JA
Waschek
Victor
V
May
Margaret A
MA
Vizzard
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