THE EFFECT OF ANALOGS OF ANGIOTENSIN-II ON DRINKING AND CARDIOVASCULAR-RESPONSES TO CENTRAL ANGIOTENSIN-II IN THE RAT

1. Intracerebroventricular (I.C.V.) infusion (60 ng h-1) of Isoleu5-angiotensin II (Isoleu5-AngII) and des-amine-angiotensin II (des-amine-AngII) in rats caused increased drinking behaviour and an increase in arterial blood pressure.2. Des-amine-AngII caused similar increases in heart rate and arterial blood pressure as AngII.3. Previous I.C.V. injection of the antagonists [Leu8]-AngII, des-amine-[Leu8]-AngII and octanoyl-[Leu8]-AngII prevented the increases in heart rate and blood pressure produced by I.C.V. infusion of AngII and caused partial reduction of the dipsogenic response.4. The three antagonists had no effect on the increase in arterial blood pressure and heart rate caused by des-amine-AngII. The drinking response was reduced by previous injection of [Leu8]-AngII and des-amine-[Leu8]-AngII but not by octanoyl-[Leu8]-AngII.5. In conclusion, Isoleu5-AngII and des-amine-AngII increase drinking behaviour, arterial blood pressure and heart rate when infused into the cerebral ventricle of rats. The study with the antagonists showed that des-amine-AngII probably binds more strongly to AngII-receptors.

Consumo de álcool entre estudantes do ensino médio do município de Passos - MG

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Consumo de álcool entre estudantes do ensino médio do município de Passos-MG

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Effect of air temperature and humidity on ingestive behaviour of sheep

Thirty-two Polwarth ewes, of ages up to 1 year, were observed in a climatic chamber (24 to 45° C) for eight periods of 5 h each. The observations were made through a window in the chamber wall. All animals were observed four times, then shorn and observed four times again. The animals were given weighed quantities of water and feed consisting of commercial concentrate plus Rhodes grass (Chloris gayana) hay. The water and feed remaining after 5 h of observation were weighed. The following traits were analysed: time eating hay (TEH), time eating concentrate (TEC), time drinking water (TDW), weight of hay eaten (WHE), weight of concentrate eaten (WCE), volume of ingested water (VIW), ruminating time standing up (RTS), ruminating time lying down (RTL), idling time standing up (ITS), and idling time lying down (ITL). Shearing had a significant effect for all traits except ITS. Shearing resulted in higher values for all traits except for ITS and ITL. Ingestion of hay (TEH and WHE) decreased with increased air temperature and humidity, while the ingestion of concentrate (TEC) and WHE) and water (TDW and VIW) increased. Rumination decreased with increased air temperature and humidity, and was higher in shorn than in unshorn sheep. © 1992 International Society of Biometeorology.