title: Effects of St John's wort and its active constituents, hypericin and hyperforin, on isolated rat urinary bladder.
abstract: OBJECTIVE
  To investigate the effect of St John's wort (SJW) and its active constituents hypericin and hyperforin on detrusor smooth muscle contractility and their possible neuroprotective role against ischaemic-like conditions, which could arise during overactive bladder disease.
  
  
  METHODS
  In whole bladders, intrinsic nerves underwent electrical field stimulation (EFS). The effect of drugs on the contractile response and its recovery in reperfusion phase (R) was monitored at different concentrations during 1 or 2 h of anoxia-glucopenia (A-G) and the first 30 min of R. The effects of the drugs were also investigated on rat detrusor muscle strips contracted with carbachol, KCl and electrically.
  
  
  RESULTS
  SJW has spasmolytic activity, which increases with increasing concentration and it worsens the damage induced by A-G/R on rat urinary bladder. Hypericin and hyperforin had no effect during ischemic-like conditions but they both exert a dual modulation of rat detrusor strips contraction. At high micromolar concentrations they showed a relaxing effect, but at submicromolar range hypericin increased the plasma membrane depolarisation and hyperforin showed a stimulatory effect on the cholinergic system.
  
  
  CONCLUSIONS
  The results of our study showed that SJW and its constituents could modulate urinary bladder contractility and even worsen A-G/R injury.
authors.affiliation: Clinica San Carlo, Milano, Italy.
authors.forename: Aurora
authors.initials: A
authors.lastname: Valeri
authors.forename: Raffaele
authors.initials: R
authors.lastname: Capasso
authors.forename: Massimo
authors.initials: M
authors.lastname: Valoti
authors.forename: Federica
authors.initials: F
authors.lastname: Pessina
mesh_terms: D000818:Animals; D000873:Anthracenes; D002217:Carbachol; D002462:Cell Membrane / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D004558:Electric Stimulation; D005947:Glucose / Q000172:deficiency; D020902:Hypericum / Q000737:chemistry*; D000860:Hypoxia / Q000150:complications; D007511:Ischemia / Q000150:complications; D008297:Male; D009119:Muscle Contraction / Q000187:drug effects*; D009130:Muscle, Smooth / Q000187:drug effects / Q000294:innervation / Q000502:physiology; D010276:Parasympatholytics / Q000494:pharmacology; D010277:Parasympathomimetics / Q000494:pharmacology; D010569:Perylene / Q000031:analogs & derivatives* / Q000494:pharmacology / Q000627:therapeutic use; D010696:Phloroglucinol / Q000031:analogs & derivatives* / Q000494:pharmacology / Q000627:therapeutic use; D010936:Plant Extracts / Q000494:pharmacology* / Q000627:therapeutic use; D011189:Potassium Chloride; D051381:Rats; D017207:Rats, Sprague-Dawley; D013729:Terpenes / Q000494:pharmacology* / Q000627:therapeutic use; D001743:Urinary Bladder / Q000187:drug effects* / Q000294:innervation / Q000502:physiology; D001745:Urinary Bladder Diseases / Q000188:drug therapy / Q000209:etiology; D053201:Urinary Bladder, Overactive / Q000150:complications* / Q000188:drug therapy
chemical_list: D000873:Anthracenes; D010276:Parasympatholytics; D010277:Parasympathomimetics; D010936:Plant Extracts; D013729:Terpenes; D010569:Perylene; D011189:Potassium Chloride; C004965:hypericin; D002217:Carbachol; D010696:Phloroglucinol; D005947:Glucose; C001654:hyperforin