Search results for "Papaver"
showing 10 items of 61 documents
Variability of isozyme pattern, chromosome number, and latex colour and components in the closely related Papaver duhium L. and P. lecoqii Lamotte in…
1995
Summary The variability of nine different isozyme systems, chromosome number, colour of fresh and dried latex and presence or absence of meconic acid was investigated in altogether 45 populations of Papaver dubium and P. lecoqii mainly from C Europe. It was found that P. dubium is hexaploid with 2n = 42 chromosomes, has brown dried latex, and contains meconic acid. P. lecoqii is tetraploid with 2n = 28 chromosomes, has red dried latex, and lacks meconic acid. The two taxa can also be distinguished by differences in three of the nine isozymes analysed, and are almost completely monomorphic for their respective isozyme pattern. It is concluded that the two taxa, which cannot be reliably disti…
Effects of Some Directly-Acting Smooth Muscle Relaxant Drugs on Isolated Human Preparations of the Upper Urinary Tract
1985
It is generally assumed that drugs which induce relaxation of smooth muscles may be of clinical importance in some urological disorders; such drugs are indeed widely used, for example in the therapy of unstable bladders or to facilitate the passage of ureteral stones. Antispasmodic action may be classified in neurotropic and musculo-tropic action; the former acting on the autonomic nervous system and the latter directly on smooth muscle cells. Examples for the first type of action are anticholinergic drugs or alpha-adrenoceptor-antagonists, whereas papaverine is a classic drug with the second type of action.
Evolution of Leaf Morphogenesis: Evidence from Developmental and Phylogenetic Data in Papaveraceae
1999
Variation of leaf morphology in Papaveraceae s.l. (including Fumariaceae and Pteridophyllum) has previously been shown to be related to developmental differences in the direction of segmentation and in blade‐petiole differentiation. Based on ontogenetic comparisons, we here distinguish polyternate, acropetal, basipetal‐pedate, basipetal‐pinnate, and divergent modes of dissection. In addition, undissected leaves occur in some taxa. Dissection modes can be grouped in two classes on the basis of blade‐petiole differentiation. Mapping of these morphogenetic traits on an independently obtained phylogenetic reconstruction reveals a high degree of homoplasy, indicating multiple evolutionary parall…
Long‐distance dispersal vs vicariance: the origin and genetic diversity of alpine plants in the Spanish Sierra Nevada
2006
Here, we investigated the origin and genetic diversity of four alpine plant species co-occurring in the Spanish Sierra Nevada and other high mountains in south-western Europe by analysis of amplified fragment length polymorphisms (AFLPs). In Kernera saxatilis, Silene rupestris and Gentiana alpina we found intraspecific phylogroups corresponding to mountain regions as predicted by the vicariance hypothesis. Moreover, genetic distances between Sierra Nevada and Pyrenees populations were always higher than those between populations from the Pyrenees and the south-western Alps/Massif Central. This suggests successive disruption of gene exchange between mountain ranges as postglacial climatic wa…
Evolution of gynoecium morphology in Old World Papaveroideae: a combined phylogenetic/ontogenetic approach.
2011
PREMISE OF THE STUDY: The correct assessment of homology is an important prerequisite for reconstructing phylogenetic relationships and character evolution. Old World Papaveroideae (Papaver, Meconopsis, Roemeria, Stylomecon) show substantial diversity in gynoecium and capsule morphology. In particular, capsules can have distinct styles (Meconopsis p.p., Stylomecon) or a sessile stigmatic disc (Papaver). Molecular phylogenetic analyses of Old World Papaveroideae had shown that neither taxa with styles nor those with stigmatic discs represent monophyletic lineages. We here investigate whether either styles or stigmatic discs have arisen repeatedly during the diversification of Old World Papav…
Floral and Vegetative Morphogenesis in California Poppy (Eschscholzia californicaCham.)
2005
For studies of the evolution of development in angiosperms, early‐diverging eudicot taxa are of particular interest for comparisons with established core eudicot model plants, such as Arabidopsis. Here we provide a detailed description of shoot and floral development of the basal eudicot California poppy (Eschscholzia californica). Rosette formation in the vegetative phase is accompanied by increased leaf complexity and shoot apex size. The flowering phase is characterized by internode elongation, formation of dissected cauline leaves, terminal flowers, and basipetal inflorescence branching. For developing flowers and fruits, we have defined 14 stages according to important landmark events,…
Papaverine enhances the negative inotropic effect of acetylcholine in rat auricles
1978
The negative inotropic effect of acetylcholine in rat left auricles is enhanced in the presence of the phosphodiesterase inhibitor papaverine. This result favours the idea of a cyclic GMP-mediated action of acetylcholine in the heart.
A negative inotropic effect of acetylcholine in the presence of several phosphodiesterase inhibitors.
1981
The phosphodiesterase inhibitors papaverine, theophylline and 3-isobutyl-1-methylxanthine (IBMX) reveal a negative inotropic effect of acetylcholine in cat ventricular heart muscle. This effect in unrelated to beta-adrenoceptor stimulation and possibly mediated by the accumulation of cyclic GMP.
Electrical and mechanical activity of mammalian heart muscle fibres treated with papaverine
1977
The action of papaverine on electrical and mechanical activity was investigated in ventricular and atrial heart muscle fibres from guinea-pigs and cats. 1. Papaverine (10−5 M–5×10−5M) had positive, negative or no inotropic effects in ventricular preparations; positive inotropic effects were not observed after pretreatment of the animals with reserpine. In atrial preparations, papaverine (2×10−5M) had a positive inotropic effect that was independent of endogenously stored catecholamines. 2. The effects of isoprenaline and dibutyryl cyclic AMP were potentiated by papaverine (10−5 M–2×10−5M). 3. The action potential duration was always prolonged by papaverine in ventricular as well as in atria…
Influence of calcium on the effects of okadaic acid and its interaction with caffeine and theophylline in rat myometrium.
1994
The effects of okadaic acid (OA), a monocarboxylic acid produced by marine dinoflagellates belonging to the genera Dinophysis and Prorocentrum, and their interactions with theophylline and caffeine were studied on the rat-isolated uterus in a calcium-containing medium and a calcium-free medium in the presence of 10−3 M EGTA. Okadaic acid (5 × 10−6 to 5 × 10−5 M) induced a concentration-dependent contraction of the rat-isolated uterus corresponding, with 5 × 10−5M, to 142.3±6.1% (n = 7) of the contraction induced by oxytocin 10−6 M. The time to peak tension was inversely proportional to the maximum effect produced. The contraction was not sustained and was followed by a concentration-depende…