title: Hypertension alters the function of nitrergic and sensory innervation in mesenteric arteries from female rats.
abstract: OBJECTIVE
  To investigate whether hypertension could modify the function of adrenergic, nitrergic, and sensory innervations involved in the electrical field stimulation-induced response in mesenteric arteries from female rats.
  
  
  METHODS
  Vascular reactivity experiments were performed in endothelium-denuded mesenteric arteries from normotensive, Wistar-Kyoto and spontaneously hypertensive female rats; protein expression was measured by western blot; nitric oxide release was measured by fluorometry; calcitonin gene-related peptide and noradrenaline release were determined by enzyme immunoassay.
  
  
  RESULTS
  The electrical field stimulation-induced contractions were significantly lower in segments from spontaneously hypertensive rats than those of Wistar-Kyoto rats. Hypertension did not modify either the response or release of noradrenaline. Preincubation with the nitric oxide synthase inhibitor N(G)-nitro-L-arginine methyl ester increased the electrical field stimulation-induced contractions only in segments from Wistar-Kyoto rats. The relaxation induced by the nitric oxide donor sodium nitroprusside was similar in segments from both strains. The electrical field stimulation-induced nitric oxide release was decreased in segments from spontaneously hypertensive rats. The calcitonin gene-related peptide receptor antagonist CGRP(8-37) did not alter the electrical field stimulation-induced contractions in segments from Wistar-Kyoto rats but increased them in segments from spontaneously hypertensive rats. The calcitonin gene-related peptide-induced relaxation was increased in segments from spontaneously hypertensive rats. The expression of the 15-kDa active form of RAMP1 was increased in segments from spontaneously hypertensive rats.
  
  
  CONCLUSIONS
  In contrast to male rats, electrical field stimulation-induced contractions are decreased in hypertensive female rats. Nitrergic innervation plays a role in the development and/or maintenance of hypertension, whereas sensory innervation is a counteracting mechanism through the increased calcitonin gene-related peptide response.
authors.affiliation: Departamento de Fisiología, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain.
authors.forename: Lara
authors.initials: L
authors.lastname: del Campo
authors.forename: Mercedes
authors.initials: M
authors.lastname: Ferrer
authors.forename: Gloria
authors.initials: G
authors.lastname: Balfagón
mesh_terms: D000818:Animals; D015740:Calcitonin Gene-Related Peptide / Q000502:physiology*; D004305:Dose-Response Relationship, Drug; D004558:Electric Stimulation; D005260:Female; D006973:Hypertension / Q000503:physiopathology*; D047908:Intracellular Signaling Peptides and Proteins / Q000032:analysis; D008297:Male; D008565:Membrane Proteins / Q000032:analysis; D008638:Mesenteric Arteries / Q000294:innervation* / Q000502:physiology; D019331:NG-Nitroarginine Methyl Ester / Q000494:pharmacology; D009569:Nitric Oxide / Q000502:physiology*; D009638:Norepinephrine / Q000502:physiology*; D051381:Rats; D011918:Rats, Inbred SHR; D011921:Rats, Inbred WKY; D058261:Receptor Activity-Modifying Proteins; D012727:Sex Characteristics; D014661:Vasoconstriction / Q000187:drug effects
chemical_list: D047908:Intracellular Signaling Peptides and Proteins; D008565:Membrane Proteins; D058261:Receptor Activity-Modifying Proteins; D009569:Nitric Oxide; D015740:Calcitonin Gene-Related Peptide; D019331:NG-Nitroarginine Methyl Ester; D009638:Norepinephrine