Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0403608 (ureter)
 9,655 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

I investigated the biochemical (Bmax, KD) and functional (contractile force) characteristics of autonomic receptors in the 1-day-old rabbit urinary tract smooth muscle, and compared the data obtained to those already reported in adult rabbits. The rank order of the receptor densities in neonatal rabbits are dome greater than base greater than urethra greater than ureter for alpha 1 (3H-PZ), ureter greater than urethra greater than base greater than dome for alpha 2 (3H-YOH), dome greater than base greater than urethra greater than ureter for beta (3H-DHA) and dome greater than base greater than urethra greater than ureter for muscarinic (3H-QNB). Unlike the findings in the adult rabbit, there is a much larger number of functional muscarinic receptors in the bladder dome and a much smaller number of functional alpha 1-receptors in the urethra of neonatal rabbits. The differences observed in the pattern of distribution of these receptors between neonatal and adult urinary tracts may play a determinant role in the physiological development of the urinary system.
 ...
PMID:[Biochemical and functional characteristics of autonomic receptors in neonatal urinary tract smooth muscle]. 204 1

1. Muscarinic receptors in the pig intravesical ureter were characterized by binding assays in which the muscarinic receptor antagonist, (-)-[3H]-quinuclidinyl benzylate ([3H]QNB) was used as radioligand. 2. The specific binding of [3H]-QNB (about 90% of the total binding, as defined with 10(-5) M unlabelled atropine) was dependent on protein concentration, saturable, and of high affinity (KD = 0.13 +/- 0.02 nM). 3. Displacement of [3H]-QNB specific binding by the M1-selective antagonist, pirenzepine, described a two-component curve, with a minor (17%) high affinity component (pKiH = 8.75), and a major (83%) low affinity one (pKiL = 6.34). The M3-preferential antagonists, hexa-hydro-sila-difenidol (HHSid) and p-fluoro-HHSiD (p-F-HHSiD) delineated also two sites, with pKiH of 8.91 and 8.57 and pKiL of 6.94 and 7.05, respectively. However, the M2-selective antagonists, 11-(2-(diethyl-amino)methyl-1-piperidinylacetyl)-5,11-dihydro-6H-p yrido-(2,3-b)- (1,4)-benzodiazepin-6-one (AF-DX 116, pKi = 6.72) and methoctramine (pKi = 8.34), as well as the M4-selective antagonists, tropicamide (pKi = 7.15) and himbacine (pKi = 8.65) fitted best to a single population of sites. Moreover, 4-diphenyl-acetoxy-N-methyl-piperidine methiodide (4-DAMP), a muscarinic antagonist that discriminates the M1 and M3 versus the M2 subtypes, also delineated one site (pKi = 8.36). 4. The antagonist profile clearly indicates the existence of an M2 population in the porcine intravesical ureter. In addition, the presence of a minor non-M2 population, which may be formed by a mixture of several muscarinic subtypes (i.e. M1, M3 and/or M4) can not be discounted. 5. The present work confirms the results obtained in previous functional studies where the stimulation of muscarinic receptors by carbachol evoked the contraction of the pig isolated intravesical ureter.
 ...
PMID:Muscarinic binding sites of the pig intravesical ureter. 874 75