Effect of melatonin on age associated changes in Guinea pig bladder function.
OBJECTIVE
The incidence of urinary incontinence increases with age but the cause and effect relationship between aging and altered bladder function is poorly understood. It was suggested that melatonin can ameliorate negative effects induced by aging by its free radical scavenging activity and its ability to decrease oxidative stress. We investigated the changes in bladder function evoked by aging and the possible benefits of melatonin treatment on age related bladder disturbances.


METHODS
Bladder function was assessed using cystometry in conscious, freely moving female guinea pigs. Animals were grouped according to age as young adults (4 months old) and senescents (18 to 20 months old). A group of senescent animals were treated with 2.5 mg kg(-1) day(-1) melatonin for 21 days.


RESULTS
Aging led to increased detrusor activity, as demonstrated by short micturition intervals, decreased bladder capacity and spontaneous contractions during the filling phase. During the voiding phase aged animals showed lower micturition pressures than young adults. Melatonin counteracted the cystometric changes in senescent animals and restored micturition parameters to those of young adults.


CONCLUSIONS
These results show that in guinea pigs aging induces detrusor overactivity. Melatonin treatment improved age induced changes in bladder function. If similar effects can be demonstrated in humans, melatonin treatment may be a new approach to decrease the impact of age related bladder disorders.
Gomez-Pinilla
Pedro J
PJ
Department of Physiology, Nursing School, University of Extremadura, Caceres, Spain.
Gomez
Maria F
MF
Hedlund
Petter
P
Swärd
Karl
K
Hellstrand
Per
P
Camello
Pedro J
PJ
Pozo
María J
MJ
Andersson
Karl-Erik
KE
D000367:Age Factors; D000818:Animals; D005260:Female; D006168:Guinea Pigs; D008550:Melatonin / Q000494:pharmacology*; D001743:Urinary Bladder / Q000187:drug effects* / Q000502:physiology*; D014563:Urodynamics
D008550:Melatonin