Nicotine modulates the renin-angiotensin system of cultured neurons and glial cells from cardiovascular brain areas of Wistar Kyoto and spontaneously hypertensive rats.
Considering the importance of the renin-angiotensin system (RAS) for the central control of blood pressure and that nicotine increases the probability of development of hypertension associated to genetic predisposition, our aims are (1) to determine RAS in cultured neurons and glia from the brainstem and hypothalamus of spontaneously hypertensive (SHR) and Wistar Kyoto (WKY) rats; (2) to analyze the possibility of nicotine to interact with brain RAS; and (3) to hypothesize any contribution of nicotine and RAS to the development of neurogenic hypertension. This study demonstrated physiological differences in RAS between cultured neuronal and glial cells from the brainstem and hypothalamus of SHR and WKY neonate rats. Our study also featured evidences of direct modulation of the RAS by nicotine in neurons and glia of brainstem and hypothalamus, which seems to be differential between the two rat strains. Such modulation gives us a clue about the mechanisms possibly involved in the genesis of neurogenic hypertension in vivo, for example, increase in angiotensin II type 1 receptor binding and decrease in angiotensin-converting enzyme 2. In conclusion, we demonstrated that neuronal and glial RAS from the brainstem and hypothalamus of SHR differ from WKY rats and nicotine differentially modulates the brain RAS in SHR and WKY.
Ferrari
Merari F R
MF
Departamento de Fisiologia, Instituto de Biociências, Universidade de São Paulo, Rua do Matão, Travessa 14, n.321, Cidade Universitária, São Paulo, SP 05508-090, Brazil. mfrf@yahoo.com
Raizada
Mohan K
MK
Fior-Chadi
Debora R
DR
D000809:Angiotensins / Q000235:genetics / Q000378:metabolism; D000818:Animals; D001933:Brain Stem / Q000166:cytology*; D002478:Cells, Cultured; D018920:Coculture Techniques; D004305:Dose-Response Relationship, Drug; D007031:Hypothalamus / Q000166:cytology*; D009457:Neuroglia / Q000166:cytology / Q000502:physiology*; D009474:Neurons / Q000166:cytology / Q000502:physiology*; D009538:Nicotine / Q000494:pharmacology*; D018722:Nicotinic Agonists / Q000494:pharmacology*; D051381:Rats; D011918:Rats, Inbred SHR; D011921:Rats, Inbred WKY; D011945:Receptors, Angiotensin / Q000378:metabolism; D012084:Renin-Angiotensin System / Q000187:drug effects*
D000809:Angiotensins; D018722:Nicotinic Agonists; D011945:Receptors, Angiotensin; D009538:Nicotine