Zinc and water intake in rats: investigation of adrenergic and opiatergic central mechanisms
| Autor: | F.L.Q. Carvalho, F.S.F. Souza, Josmara Bartolomei Fregoneze, de-Castro-e-Silva E, C.P. Luz, L. Castro, M.G. Ferreira, Patricia Santos de Oliveira, M.A. Rocha, A.K.S. Lima, I.P.V. Bandeira, Igor Lima Maldonado, D.F. Macêdo |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 1999 |
| Předmět: |
Male
medicine.medical_specialty Time Factors Physiology Narcotic Antagonists Immunology Biophysics Drinking chemistry.chemical_element Adrenergic Stimulation Zinc (+)-Naloxone Biochemistry Thirst Internal medicine Receptors Adrenergic beta medicine Animals General Pharmacology Toxicology and Pharmaceutics Rats Wistar Opioid peptide lcsh:QH301-705.5 Injections Intraventricular lcsh:R5-920 Dehydration Dose-Response Relationship Drug naloxone isoproterenol General Neuroscience zinc opioids Cell Biology General Medicine Adrenergic beta-Agonists rats Endocrinology chemistry Opioid Opioid Peptides thirst lcsh:Biology (General) Cholinergic medicine.symptom lcsh:Medicine (General) medicine.drug |
| Zdroj: | Brazilian Journal of Medical and Biological Research, Vol 32, Iss 10, Pp 1217-1222 (1999) ResearcherID Brazilian Journal of Medical and Biological Research, Volume: 32, Issue: 10, Pages: 1217-1222, Published: OCT 1999 |
| Popis: | We have demonstrated that central administration of zinc in minute amounts induces a significant antidipsogenic action in dehydrated rats as well as in rats under central cholinergic and angiotensinergic stimulation. Here we show that acute third ventricle injections of zinc also block water intake induced by central ss-adrenergic stimulation in Wistar rats (190-250 g). Central inhibition of opioid pathways by naloxone reverses the zinc-induced antidipsogenic effect in dehydrated rats. After 120 min, rats receiving third ventricle injections of isoproterenol (160 nmol/rat) exhibited a significant increase in water intake (5.78 +/- 0.54 ml/100 g body weight) compared to saline-treated controls (0.15 +/- 0.07 ml/100 g body weight). Pretreatment with zinc (3.0, 30.0 and 300.0 pmol/rat, 45 min before isoproterenol injection) blocked water intake in a dose-dependent way. At the highest dose employed a complete blockade was demonstrable (0.54 +/- 0.2 ml/100 g body weight). After 120 min, control (NaAc-treated) dehydrated rats, as expected, exhibited a high water intake (7.36 +/- 0.39 ml/100 g body weight). Central administration of zinc blocked this response (2.5 +/- 0.77 ml/100 g body weight). Naloxone pretreatment (82.5 nmol/rat, 30 min before zinc administration) reverted the water intake to the high levels observed in zinc-free dehydrated animals (7.04 +/- 0.56 ml/100 g body weight). These data indicate that zinc is able to block water intake induced by central ss-adrenergic stimulation and that zinc-induced blockade of water intake in dehydrated rats may be, at least in part, due to stimulation of central opioid peptides. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|