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Temnadenia odorifera is an endemic species from the Brazilian Atlantic Forest. This study was developed in order to identify the volatile compounds emitted by the living flowers and nectar, to evaluate the temporal pattern of scent emission, and the sugars composition of its nectar. Analyses of the flower scent by dynamic headspace in vivo, of nectar sugar composition and studies on floral biology were performed. Twenty-three volatile compounds were identified in the flowers scent. The total amount of odor emitted by flowers varied significantly throughout anthesis, ranging from 10232.7 ng g-1 (9 to 12 h) to 620.2 ng g-1 (15 to 18 h). 2-Phenylethanol and (E)-cinnamyl alcohol were the major compounds. Concentration ratio between disaccharides and the sum of hexoses ranged from 2.3 to 3.04, which can be correlated to the physiological needs inherent to big bees, the most frequent insects in T. odorifera. Analysis of the chemical composition of T. odorifera flowers provided a broader understanding of the mechanisms responsible for plant-insect interactions.

Bradykinin (BK) and des-Arg(9)-bradykinin (DBK) of kallikrein-kinin system exert its effects mediated by the B2 (B2R) and B1 (B1R) receptors, respectively. It was already shown that the deletion of kinin B1R or of B2R induces upregulation of the remaining receptor subtype. However studies on overexpression of B1R or B2R in transgenic animals have supported the importance of the overexpressed receptor but the expression of another receptor subtype has not been determined. Previous study described a marked vasodilatation and increased susceptibility to endotoxic shock which was associated with increased mortality in response to DBK in thoracic aorta from transgenic rat overexpressing the kinin B1R (TGR(Tie2B1)) exclusively in the endothelium. In another study, mice overexpressing B1R in multiple tissues were shown to present high susceptibility to inflammation and to lipopolysaccharide-induced endotoxic shock. Therefore the role of B2R was investigated in the thoracic aorta isolated from TGR(Tie2B1) rats overexpressing the B1R exclusively in the vascular endothelium. Our findings provided evidence for highly increased expression level of the B2R in the transgenic rats. It was reported that under endotoxic shock, these rats exhibited exaggerated hypotension, bradycardia and mortality. It can be suggested that the high mortality during the pathogenesis of endotoxic shock provoked in the transgenic TGR(Tie2B1) rats could be due to the enhanced expression of B2R associated with the overexpression of the B1R.

The chemical composition of the essential oil from the leaves of Pseudobrickellia brasiliensis (Asteraceae) from the Brazilian Cerrado was analyzed by GC/FID and GC/MS. Thirty-four out of thirty-eight components detected were identified. Major compounds in the oil were terpinen-4-ol (38.6%), γ-terpinene (19.5%), α-terpinene (7.8%) and α-terpineol (4.5%).

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