Aizawa N, Iijima K, Rosenbaum JS, Downs TR, Igawa Y, Andersson KE, Wyndaele JJ. Comparison of the effects of oestrogen deficiency and old age on primary bladder afferent activity and voiding behaviour in the ageing female rat.
BJU Int 2010;
108:E10-6. [PMID:
20875090 DOI:
10.1111/j.1464-410x.2010.09689.x]
[Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
OBJECTIVE
To determine if a decrease in oestrogen (E) levels increases activity in bladder afferent nerves, by investigating the effects of E loss on afferent nerve activity in ovariectomized (OVX) rats, and making comparisons with findings in ageing female rats.
MATERIALS AND METHODS
Female Sprague-Dawley rats were divided into four groups: ageing; OVX+ E; OVX+ vehicle (V); and sham-operated (SHAM) + V. The E (250 µg/kg) or V (cottonseed oil) was injected s.c. once a week for 8 weeks. Frequency-volume recordings were performed with the rats in metabolic cages, and single Aδ- or C-fibre activities from the bladder were measured. After measurements, the blood serum was collected and the estradiol (E2) level was measured.
RESULTS
The C-fibre activity of OVX + V rats was significantly lower than in the other groups. Aδ-fibre activity was unchanged. Despite low E2 levels, ageing rats showed high afferent activity and voiding frequency.
CONCLUSION
Although a low E level may affect storage function, it is unlikely that it is the main cause of the high afferent activity and voiding frequency observed in the ageing female rat.
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