How the proliferation of the urothelium is regulated is known to a little degree. E. coli lipopolysaccharide (LPS) activates the innate immune response of the urinary bladder via the Toll-like receptor 4 (TLR4) on the urothelium but induces also urothelial proliferation. We wanted to assess whether muscarinic receptors are involved in the regulation of urothelial proliferation triggered by LPS stimulation. Female Fischer 344 rats were instilled with LPS or saline (control) in the urinary bladder in the absence or presence of muscarinic receptor blockade with atropine and regeneration of the urothelium was assessed 4h and 24h later. In the Fischer 344 bladder, urothelial thinning and urothelial caspase 3 up-regulation occurred at 4h after LPS urinary bladder instillation, which were totally blocked in rats pre-treated with atropine. TLR4 was only expressed in blood vessels in the Fischer 344 bladder, while it was also expressed in umbrella cells in the Sprague-Dawley bladder. Proliferation (Ki67 incorporation) of the human urothelial cell line UROtsa was reduced in the presence of the muscarinic receptor antagonists methoctramine (M2/M4-selective) and pirenzepine (M1/M4-selective), while proliferation instead was enhanced in the presence of atropine. In UROtsa cells exposed to LPS for 24h, 4-DAMP (M3/M1/M5-selective) inhibited instead proliferation. In conclusion, muscarinic receptors regulate urothelial proliferation and LPS may induce urothelial apoptosis via muscarinic receptor-dependent pathways. Our findings also suggest that species differences exist in the expressional pattern of TLR4 in the urothelium.
International Immunopharmacology – Elsevier
Published: Mar 1, 2018
It’s your single place to instantly
discover and read the research
that matters to you.
Enjoy affordable access to
over 18 million articles from more than
15,000 peer-reviewed journals.
All for just $49/month
Query the DeepDyve database, plus search all of PubMed and Google Scholar seamlessly
Save any article or search result from DeepDyve, PubMed, and Google Scholar... all in one place.
Get unlimited, online access to over 18 million full-text articles from more than 15,000 scientific journals.
Read from thousands of the leading scholarly journals from SpringerNature, Elsevier, Wiley-Blackwell, Oxford University Press and more.
All the latest content is available, no embargo periods.
“Hi guys, I cannot tell you how much I love this resource. Incredible. I really believe you've hit the nail on the head with this site in regards to solving the research-purchase issue.”Daniel C.
“Whoa! It’s like Spotify but for academic articles.”@Phil_Robichaud
“I must say, @deepdyve is a fabulous solution to the independent researcher's problem of #access to #information.”@deepthiw
“My last article couldn't be possible without the platform @deepdyve that makes journal papers cheaper.”@JoseServera