title: Nitric oxide in the commissural nucleus tractus solitarii regulates carotid chemoreception hyperglycemic reflex and c-Fos expression.
abstract: Carotid body chemoreceptors function as glucose sensors and contribute to glucose homeostasis. The nucleus tractus solitarii (NTS) is the first central nervous system (CNS) nuclei for processing of information arising in the carotid body. Here, we microinjected a nitric oxide (NO) donor sodium nitroprusside (SNP), an NO-independent activator of the soluble guanylyl cyclase (sGC) (YC₁) or an NO-synthase (NOS) inhibitor Nω-nitro-l-arginine methyl ester (L-NAME) into the commissural NTS (cNTS) before carotid chemoreceptor anoxic stimulation and measured arterial glucose and the expression of Fos-like immunoreactivity (Fos-ir). Male Wistar rats (250-300 g) were anesthetized, and the carotid sinus was vascularly isolated. Either artificial cerebrospinal fluid (aCSF), SNP, YC₁ or L-NAME were stereotaxically injected into the cNTS. The SNP and YC₁ infused into the cNTS before carotid chemoreceptor stimulation (SNP-2 and YC₁-2 groups) similarly increased arterial glucose compared to the aCSF-2 group. By contrast, infusion of L-NAME into the cNTS before carotid chemoreceptor stimulation (L-NAME-2 group) decreased arterial glucose concentration. The number of cNTS Fos-ir neurons, determined in all the groups studied except for YC₁ groups, significantly increased in SNP-2 rat when compared to the aCSF-2 or SNP-2 groups. Our findings demonstrate that NO signaling, and the correlative activation of groups of cNTS neurons, plays key roles in the hyperglycemic reflex initiated by carotid chemoreceptor stimulation.
authors: Centro Universitario de Investigaciones Biomédicas, Universidad de Colima, Ave. 25 de Julio s/n, Colima 28045, Mexico; Facultad de Medicina, Universidad de Colima, Ave. 25 de Julio s/n, Colima 28045, Mexico.
authors: Sergio
authors: S
authors: Montero
authors: Centro Universitario de Investigaciones Biomédicas, Universidad de Colima, Ave. 25 de Julio s/n, Colima 28045, Mexico.
authors: Mónica
authors: M
authors: Lemus
authors: Departamento de Neurociencias, Centro Universitario de Ciencias de la Salud, Universidad de Guadalajara, Mexico.
authors: Sonia
authors: S
authors: Luquin
authors: División de Neurociencias, Centro de Investigación Biomédica de Occidente, IMSS, Guadalajara, Mexico.
authors: Joaquín
authors: J
authors: Garcia-Estrada
authors: Facultad de Medicina, Universidad de Colima, Ave. 25 de Julio s/n, Colima 28045, Mexico.
authors: Valery
authors: V
authors: Melnikov
authors: División de Investigación Quirúrgica, Centro de Investigación Biomédica de Occidente, IMSS, Guadalajara, Mexico.
authors: Caridad Aurea
authors: CA
authors: Leal
authors: División de Investigación Quirúrgica, Centro de Investigación Biomédica de Occidente, IMSS, Guadalajara, Mexico.
authors: Eliseo
authors: E
authors: Portilla-de Buen
authors: Centro Universitario de Investigaciones Biomédicas, Universidad de Colima, Ave. 25 de Julio s/n, Colima 28045, Mexico. Electronic address: nuskaroces@gmail.com.
authors: Elena
authors: E
authors: Roces de Álvarez-Buylla
mesh_terms: D000818:Animals; D001786:Blood Glucose; D002339:Carotid Arteries / Q000187:drug effects / Q000378:metabolism; D002344:Carotid Body / Q000378:metabolism*; D002628:Chemoreceptor Cells / Q000378:metabolism; D005786:Gene Expression Regulation; D005947:Glucose / Q000378:metabolism; D006706:Homeostasis; D006943:Hyperglycemia / Q000378:metabolism*; D000860:Hypoxia; D008297:Male; D019331:NG-Nitroarginine Methyl Ester / Q000737:chemistry; D009474:Neurons / Q000187:drug effects / Q000378:metabolism; D009569:Nitric Oxide / Q000378:metabolism*; D020030:Nitric Oxide Donors / Q000737:chemistry; D009599:Nitroprusside / Q000737:chemistry; D016760:Proto-Oncogene Proteins c-fos / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D015398:Signal Transduction; D012966:Sodium Cyanide / Q000737:chemistry; D017552:Solitary Nucleus / Q000378:metabolism*
chemical_list: D001786:Blood Glucose; D020030:Nitric Oxide Donors; D016760:Proto-Oncogene Proteins c-fos; D009599:Nitroprusside; D009569:Nitric Oxide; D005947:Glucose; D012966:Sodium Cyanide; D019331:NG-Nitroarginine Methyl Ester
keywords: Arterial glucose; Commissural nucleus tractus solitarii; Fos-ir; Glucose sensing; Nitric oxide; Sodium cyanide