Muscarinic receptor subtypes in human bladder detrusor and mucosa, studied by radioligand binding and quantitative competitive RT-PCR: changes in ageing.
1. We investigated muscarinic receptors in the detrusor and mucosa of the human bladder body. Radioligand-binding studies with [(3)H]QNB were conducted using specimens collected from patients (36-77 years) with normal bladder function, undergoing surgery. For RT-PCR, biopsies of normal bladder were obtained from patients (30-88 years) undergoing check cystoscopy. 2. Binding of [(3)H]QNB in detrusor (n=20) was of high affinity (K(D) 77.1 (55.2-99.0) pM) and capacity (B(max) 181+/-7 fmol mg protein(-1)). Similar values were obtained in mucosa (n=6) (K(D) 100.5 (41.2-159.9) pM; B(max) 145+/-9 fmol mg protein(-1)). 3. Competition-binding experiments in detrusor membranes with muscarinic receptor antagonists including trospium, darifenacin, 4-DAMP, methoctramine, AQ-RA 741, AF-DX 116 and pirenzepine indicated a receptor population of 71% M(2), 22% M(3) and 7% M(1). In the mucosa, 75% of sites were M(2) receptors, with 25% M(3)/M(5). 4. Using RT-PCR, expression of M(1), M(2), M(3) and M(5) mRNA was demonstrated in both detrusor and mucosa. 5. The presence of a high density of mainly M(2) muscarinic receptors in the mucosa appears to be a novel finding and raises the question of their physiological significance and the source of their endogenous ligand. 6. There was a negative correlation of receptor number (B(max)) with age in detrusor muscle from male patients (P=0.02). Quantitative competitive RT-PCR demonstrated a selective age-related decrease in mRNA for muscarinic M(3) but not M(2) receptors, in both male (P<0.0001) and female (P=0.019) detrusor. These findings correspond with reports of decreased detrusor contractility with ageing.
Mansfield
Kylie J
KJ
Department of Physiology and Pharmacology, University of New South Wales, Sydney, NSW 2052, Australia.
Liu
Lu
L
Mitchelson
Frederick J
FJ
Moore
Kate H
KH
Millard
Richard J
RJ
Burcher
Elizabeth
E
D000328:Adult; D000368:Aged; D000375:Aging / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009092:Mucous Membrane / Q000378:metabolism; D011485:Protein Binding / Q000502:physiology; D020033:Protein Isoforms / Q000145:classification* / Q000378:metabolism; D011813:Quinuclidinyl Benzilate / Q000378:metabolism; D011869:Radioligand Assay / Q000379:methods*; D011976:Receptors, Muscarinic / Q000145:classification* / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods*; D001743:Urinary Bladder / Q000378:metabolism*
D020033:Protein Isoforms; D011976:Receptors, Muscarinic; D011813:Quinuclidinyl Benzilate
J Urol. 2001 Aug;166(2):721-7
11458124
BJU Int. 2001 Jun;87(9):760-6
11412210
Br J Pharmacol. 2002 Jul;136(5):641-3
12086973
J Auton Pharmacol. 2001 Oct-Dec;21(5-6):243-8
12123469
J Urol. 2002 Sep;168(3):1027-31
12187215
Nat Neurosci. 2002 Sep;5(9):856-60
12161756
Urology. 2002 Oct;60(4):719-25
12385950
Auton Autacoid Pharmacol. 2002 Jun;22(3):133-45
12452898
J Neurosci. 2002 Dec 15;22(24):10627-32
12486155
Eur Urol. 2003 Jan;43(1):1-5
12507537
Am J Physiol Regul Integr Comp Physiol. 2003 Sep;285(3):R701-8
12763741
J Urol. 2003 Nov;170(5):1897-900
14532802
Life Sci. 2003 Dec 5;74(2-3):355-66
14607264
Eur J Pharmacol. 2003 Dec 15;482(1-3):101-9
14660010
Urology. 2004 Mar;63(3 Suppl 1):17-23
15013648
Urology. 2004 Mar;63(3 Suppl 1):24-31
15013649
Am J Physiol Regul Integr Comp Physiol. 2004 May;286(5):R874-80
14751843
J Urol. 1985 Aug;134(2):418-23
4020999
J Urol. 1986 Aug;136(2):492-6
2874237
J Urol. 1989 Sep;142(3):869-74
2769884
J Pharmacol Exp Ther. 1990 May;253(2):661-7
2338651
J Urol. 1995 May;153(5):1688-92
7715011
J Pharmacol Exp Ther. 1995 May;273(2):959-66
7752101
Pharmacol Rev. 1996 Dec;48(4):531-65
8981565
J Physiol. 1997 Dec 1;505 ( Pt 2):503-11
9423189
Urology. 1998 Feb;51(2):206-12
9495699
Urol Res. 1998;26(2):149-54
9631949
World J Urol. 1998;16 Suppl 1:S10-34
9775413
Life Sci. 1999;64(6-7):411-8
10069504
Life Sci. 1995;56(11-12):899-906
10188791
Br J Pharmacol. 2000 Feb;129(3):416-9
10711338
Br J Pharmacol. 2000 Feb;129(3):493-500
10711347
Brain Res Mol Brain Res. 2000 Mar 29;76(2):347-54
10762711
Br J Pharmacol. 2000 May;130(1):13-21
10780992
Proc Natl Acad Sci U S A. 2000 Aug 15;97(17):9579-84
10944224
J Virol Methods. 2000 Oct;90(1):15-23
11011077
J Pharmacol Exp Ther. 2000 Dec;295(3):879-88
11082420
Exp Gerontol. 2001 Jan;36(1):99-109
11162915
J Urol. 2002 Feb;167(2 Pt 1):742-5
11792964