Effects of intracerebroventricular infusion of angiotensin II and related peptides on water and sodium ingestion and excretion

The objetive of the present study was to investigate the effects of an angiotensin II (AII) analogue, Des-Asp1-AII and of two competitive blockers, [Leu8]-AII and [octanoyl-Leu8]-AII, infused intracerebroventriculary on the ingestion of water and of a 3% NaCl solution, as well as on diuresis and natriuresis in normal rats and in adrenalectomized and deoxycorticosterone (DOCA)-treated rats. Both AII and Des-Asp1-AII increased water and 3% NaCl intake and increased urine and Na+ excretion, the effect of AII being more intense. Except for 3% NaCl, the responses of all other parameters were totally or partially reduced by previous treatment with [Leu8]-AII or [octanoyl-Leu8]-AII. Subcytaneous DOCA injection caused water ingestion. Previous treatment with DOCA increased the response to AII for the ingestion of 3% NaCl and inhibited sodium excretion. The results obtained for adrenalectomized rats treated with DOCA, AII and analogous agonists did not differ from those observed in normal rats. These data suggest a possible synergism between the cerebral and renal renin-angiotensin systems in the regulation of the physiological parameters studied

Structure-activity relationships of 110 candidate juvenile hormone analogues for Panstrongylus megistus (Burmeister,1835) a vector of Chagas disease (Hemiptera, Reduviidae, Triatominae).

Procurando novas alternativas para combater triatomineos vetores da doenca de Chagas, estudou-se a atividade de 110 compostos quanto a sua capacidade de juvenilizar P. megistus, quando aplicados topicamente no inicio do quinto estadio. Foram testados compostos pertencentes a varias classes estruturais, estabelecendo-se posteriormente algumas relacoes entre estrutura e atividade. Seis compostos revelaram grande atividade: os eteres aromaticos com cadeia terpenoidal, 3,7-dimetil6,7- epoxi - 1-(3,4-metilenodioxifenoxi) -2noneno e seu analogo 3-etil-7-metil; os derivados da N-geranilanilina, N-(2,5-diclorofenil) -3,7- dimetil -2,6- octadienilamina, seu analogo N-(5-cloro-2-metilfenil), e a N-(5cloro-2-metilfenil)-3,7-dimetil -7-metoxi -2octenilamina, alem do arilterpenoide com esqueleto constituido somente por carbono, 4,8dimetil-7,8-epoxi-1-(3-metoxifenil)-3-noneno.Estes compostos foram capazes de induzir grau medio de juvenilizacao entre 3,9 e 4,0 (sendo 4,0 o grau maximo) e 100% de insetos juvenilizados na dosagem de 1 micro g/ninfa, preservando ainda alguma atividade na dosagem de 0,1 micro g/ninfa. Todos os compostos altamente ativos tinham um substituinte eletronegativo no anel aromatico, com orientacao meta em relacao a cadeia lateral terpenoidal