TY  - JOUR
A1  - Martin, Craig E.
A1  - Herppich, Werner B.
A1  - Roscher, Yvonne
A1  - Burkart, Michael
T1  - Relationships between leaf succulence and Crassulacean acid metabolism in the genus Sansevieria (Asparagaceae)
JF  - Flora : morphology, distribution, functional ecology of plants
N2  - Relationships between different measures of succulence and Crassulacean acid metabolism (CAM; defined here as nocturnal increases in tissue acidity) were investigated in leaves of ten species of Sansevieria under greenhouse conditions. CAM was found in seven of the ten species investigated, and CAM correlated negatively with leaf thickness and leaf hydrenchyma/chlorenchyma ratio. Similarly, CAM correlated negatively with leaf water content, but only when expressed on a fresh mass basis. CAM was not correlated with "mesophyll succulence", but weakly with leaf chlorophyll concentration. These results indicate that CAM is associated more with "all-cell succulence" and not with the amount of leaf hydrenchyma in the genus Sansevieria. The findings of this study emphasize the importance of defining the nature of "leaf succulence" in studies of photosynthetic pathways and leaf morphology. Evidence is also provided that CAM and succulence arose multiple times in the genus Sansevieria.
KW  - Anatomy
KW  - CAM
KW  - Chlorenchyma
KW  - Chlorophyll
KW  - Hydrenchyma
KW  - Morphology
KW  - Phylogeny
Y1  - 2019
U6  - https://doi.org/10.1016/j.flora.2019.151489
SN  - 0367-2530
SN  - 1618-0585
VL  - 261
PB  - Elsevier
CY  - München
ER  - 
TY  - GEN
A1  - Watanabe, Yuji
A1  - Püschel, Gerhard Paul
A1  - Gardemann, Andreas
A1  - Jungermann, Kurt
T1  - Presinusoidal and proximal intrasinusoidal confluence of hepatic artery and portal vein in rat liver : functional evidence by orthograde and retrograde bivascular perfusion
N2  - The site of confluence of the artery and the portal vein in the liver still appears to be controversial. Anatomical studies suggested a presinusoidal or an intrasinusoidal confluence in the first, second or even final third of the sinusoids. The objective of this investigation was to study the problem with functional biochemical techniques. Rat livers were perfused through the hepatic artery and simultaneously either in the orthograde direction from the portal vein to the hepatic vein or in the retrograde direction from the hepatic vein to the portal vein. Arterial how was linearly dependent on arterial pressure between 70 cm H2O and 120 cm H2O at a constant portal or hepatovenous pressure of 18 cm H2O. An arterial pressure of 100 cm H2O was required for the maintenance of a homogeneous orthograde perfusion of the whole parenchyma and of a physiologic ratio of arterial to portal how of about 1:3. Glucagon was infused either through the artery or the portal vein and hepatic vein, respectively, to a submaximally effective ''calculated'' sinusoidal concentration after mixing of 0.1 nmol/L. During orthograde perfusions, arterial and portal glucagon caused the same increases in glucose output. Yet during retrograde perfusions, hepatovenous glucagon elicited metabolic alterations equal to those in orthograde perfusions, whereas arterial glucagon effected changes strongly reduced to between 10% and 50%. Arterially infused trypan blue was distributed homogeneously in the parenchyma during orthograde perfusions, whereas it reached clearly smaller areas of parenchyma during retrograde perfusions. Finally, arterially applied acridine orange was taken up by all periportal hepatocytes in the proximal half of the acinus during orthograde perfusions but only by a much smaller portion of periportal cells in the proximal third of the acinus during retrograde perfusions. These findings suggest that in rat liver, the hepatic artery and the portal vein mix before and within the first third of the sinusoids, rather than in the middle or even last third.
T3  - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - paper 067 
KW  - Hepatic artery
KW  - Portal vein
KW  - Confluence
KW  - Rat
KW  - Animal
KW  - Experimental study
KW  - Anatomy
KW  - Biochemical analysis
KW  - Technique
KW  - Perfusion
KW  - Exploration
Y1  - 1994
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-16702
ER  -