Loading…
Bradykinin increases intracellular calcium levels in rat testis peritubular cells via the B 2 receptor subtype
RT–PCR and Western blots were used to detect bradykinin B 2 receptors in testis and isolated peritubular cells of pre‐pubertal rats. RT–PCR demonstrated expression of a single transcript, whereas Western blots showed up to three specific bands that were in accordance with the described native, glyco...
Saved in:
| Published in: | British journal of pharmacology 2003-01, Vol.138 (2), p.351-358 |
|---|---|
| Main Authors: | , , , , |
| Format: | Article |
| Language: | English |
| Citations: | Items that this one cites Items that cite this one |
| Online Access: | Get full text |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| Summary: | RT–PCR and Western blots were used to detect bradykinin B
2
receptors in testis and isolated peritubular cells of pre‐pubertal rats. RT–PCR demonstrated expression of a single transcript, whereas Western blots showed up to three specific bands that were in accordance with the described native, glycosylated and dimeric form of B
2
receptor proteins, respectively.
Fura‐2‐loaded peritubular cells responded with an instantaneous, linear and transient rise in [Ca
2+
]
i
after adding bradykinin. Stimulation of cells with bradykinin concentrations between 1 μ
M
and 1 p
M
showed a dose dependent increase of [Ca
2+
]
i
. The calcium response to bradykinin was diminished after stimulation of peritubular cells in calcium‐free buffer. After blocking the SERCA‐pumps by thapsigargin and subsequent stimulation with bradykinin, no rise of [Ca
2+
]
i
was appreciated.
Multiple stimulation of a single peritubular cell by local perfusion with a brief addition of BK (10 n
M
) resulted in a fast and immediate response. However, the second and third stimuli had slower rise rates and diminished [Ca
2+
]
i
peaks, showing desensitization of the kinin receptor.
Addition of the bradykinin B
1
receptor agonist [des‐Arg
9
]‐bradykinin (100 n
M
) to Fura‐2‐loaded peritubular cells did not change the [Ca
2+
]
i
. However, the B
2
receptor antagonist HOE 140 (100 n
M
) strongly inhibited the bradykinin‐induced calcium response.
We conclude that the bradykinin‐induced increase in [Ca
2+
]
i
, in testicular peritubular cells is mediated by the stimulation of kinin receptors of the B
2
subtype.
British Journal of Pharmacology
(2003)
138
, 351–358. doi:
10.1038/sj.bjp.0705039 |
|---|---|
| ISSN: | 0007-1188 1476-5381 |
| DOI: | 10.1038/sj.bjp.0705039 |