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At least 145 records · Page 8Linked to original sources
PubMed1979

Laboratory production of ergot alkaloids by species of balansia.

Four species of Balansia (clavicipitaceous systemic grass pathogens) isolated from pastures where cattle showed signs of ergot toxicity were grown in culture. Balansia epichloë, one isolate of B. claviceps, B. henningsiana and two isolates of B. strangulans produced conidia in submerged culture during the first stage of a two-stage fermentation procedure. When tranferred to a glucose/sorbitol/inorganic salts medium during the second stage, these four species produced ergot alkaloids in stationary cultures. The transfer of fungi cultured in the first medium to the second medium was necessary for alkaloid biosynthesis. One isolate of B. claviceps did not produce alkaloids. Balansia epichloë produced chanoclavine (I), agroclavine, penniclavine, elymoclavine, ergonovine and ergonovinine. Balansia claviceps produced chanoclavine (I), ergonovine and ergonovinine. This is the first report of isolating ergonovine and ergonovinine, two lysergic acid derivatives, from fungi outside the genus Claviceps. Only chanoclavine (I) was identified from extracts of B. strangulans and B. henningsiana. Chanoclavine (I) and ergonovine were identified from smut grass (Sporobolus poiretii) parasitized by B. epichloë, indicating that this endophyte produces alkaloids both in vivo and in vitro.

Ascomycota↗
PubMed1979

Electroencephalographic and clinical changes as correlated in geriatric patients treated three months with an ergot alkaloid preparation.

The results of a 3-month trial with an ergot alkaloid preparation (Hydergine) in 16 geriatric patients showed that, in accordance with a previously proposed working hypothesis, the improvement induced by the drug in electroencephalographic age-related changes was accompanied by clinical improvement in patients with similarly age-related mental deterioration.

Affective Symptoms↗
PubMed1993

Experimental Parkinson's disease in monkeys. Effect of ergot alkaloid derivative on lipid peroxidation in different brain areas.

The effects of the Parkinsonism induced by the neurotoxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) were evaluated in four different monkey brain areas (frontal and occipital cortex, caudate putamen, substantia nigra). The basal and stimulated lipid peroxidation and the reduced glutathione (GSH) concentration were evaluated in three groups of male Macaca fascicularis monkeys (6 animals/group): (a) controls; (b) MPTP-treated animals; (c) animals treated with MPTP and alpha-dihydroergocryptine (DEK; ergot alkaloid characterized by a dopaminergic agonist action). In MPTP-treated animals the GSH concentration was unchanged or decreased in a non-significant way in the frontal and occipital cortex, and in substantia nigra. The basal thiobabituric acid reactive substance (TBARS) concentrations were significantly higher in the caudate putamen and substantia nigra of MPTP-treated animals. In the MPTP-treated monkeys the DEK administration induced a restoration of basal TBARS values to nearly normal ones. By incubating tissue from different brain areas with FeSO4 plus ascorbic acid, the stimulation of lipid peroxidation decreased the TBARS production in the substantia nigra of the MPTP-treated animals. These results, taken together, may indicate that an increased lipid peroxidation could possibly play a role in producing the Parkinson-like syndrome by MPTP and that a free radical excess could be responsible for the degeneration of the substantia nigra. The treatment with an ergot alkaloid (i.e., alpha-dihydroergocryptine) partially antagonizes the MPTP-induced increase in basal TBARS concentration in caudate putamen.

1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine↗
PubMed1992

[Nicergoline, an ergot alkaloid, improves ischemic brain damage by ameliorating the decreased cerebral blood flow and metabolism in spontaneously hypertensive rats].

Effects of ergot alkaloids, nicergoline (NIC), on survival rate, brain water content, local cerebral blood flow (LCBF: 14C-iodoantipyrine) and glucose utilization (LCGU: 14C-2-deoxyglucose) were examined after bilateral carotid artery occlusion (BCAO) in spontaneously hypertensive rats. Two series of study were performed; the permanent BCAO and 3-hr-BCAO study. After permanent BCAO, the survival rate at 24 hrs of 32% (8 mg/kg, i.p.) or 38% (16mg/kg) in NIC group was higher than that in non-treated group (12%). At the end of 3-hr-BCAO, the increase in water content (dry-wet) in di-mesencephalon was less in NIC (100 micrograms/kg/min, i.v.) group than that in non-treated group. The decrease in LCBF in caudate-putamen (CP), parietal cortex (PC), thalamus (TH), hypothalamus (HT), and substantia nigra (SN) were less in NIC group than those in non-treated group. At the 2-hr-reperfusion after 3-hr-BCAO, the decrease in LCBF in TH and HT were less in NIC group than those in non-treated group. The LCGU in sensory motor cortex, CP, PC, HT, inferior colliculus and pons-reticular were higher in NIC group than those in non-treated group. From these results, it is concluded that nicergoline may have ameliorative effects on survival rate related to the prevention of decreased cerebral blood flow and metabolism following brain ischemia.

Animals↗
PubMed2003

Effect of ergot alkaloids on 3H-flunitrazepam binding to mouse brain GABAA receptors.

In vitro effects of dihydroergotoxine, dihydroergosine, dihydroergotamine, alpha-dihydroergocriptine (ergot alkaloids), diazepam, methyl-beta-Carboline-3-carboxilate (beta-CCM), flumazenil (benzodiazepines), gamma-amino butyric acid (GABA) and thiopental (barbiturate) were studied on mouse brain (cerebrum minus cerebral cortex) benzodiazepine binding sites labeled with 3H-flunitrazepam. Specific, high affinity (affinity constant, Kd = 57.7 8.6 nM) binding sites for 3H-flunitrazepam on mouse brain membranes were identified. All benzodiazepine drugs inhibited 3H-flunitrazepam binding with nanomolar potencies. In contrast to benzodiazepines, all ergot drugs, GABA and thiopental produced an enhancement of 3H-flunitrazepam binding to its binding site at the GABAA receptor of the mouse brain. The rank order of potency was: neurotransmitter (GABA) > dihydroergotoxine > thiopental > alpha-dihydroergocriptine > dihydroergosine > dihydroergotamine. The results suggest that dihydrogenated ergot derivatives do not bind to the brain benzodiazepine binding sites labeled with 3H-flunitrazepam. However, an enhancement of 3H-flunitrazepam binding by all ergot drugs tested, clearly identifies an allosteric interaction with the benzodiazepine binding sites of GABAA receptors.

Animals↗
PubMed1971

Treatment of non-puerperal galactorrhoea with an ergot alkaloid.

Three patients suffering from non-puerperal galactorrhoea over periods ranging from two months to six years were treated with an ergot alkaloid, 2-Br-alpha-ergocryptine (CB 154). In all three cases the galactorrhoea was terminated. The apparent prolactin antagonism exhibited by this compound is discussed.

Adult↗
PubMed1980

Inhibitory effects of ergot alkaloids and their derivatives on the excitability of an identifiable giant neurone of the African giant snail (Achatina fulica Férussac).

The effects of ergot alkaloids and their derivatives on the excitability of an identifiable giant neurone, TAN (tonically autoactive neurone), found in the suboesophageal ganglia of the African giant snail (Achatina fulica Férussac) were examined. Ergometrine and methylergometrine had the strongest inhibitory effects. The critical concentrations were 3 X 10(-5) approximately 10(-4) kg/l. The three hydrogenated ergot derivatives, 9, 10-dihydroergocristine, 9, 10-dihydroergocryptine and 9, 10-dihydroergocornine, had weaker inhibitory effects than those of ergometrine and methylergometrine. The other substances examined, including D-lysergic acid, D-lysergic acid amide, D-lysergic acid piperidinamide, had no effect. Some of the substances examined, for example, lysergine, agroclavine, elymoclavine, nicergoline, ergotamine, bromocriptine and lergotrile, at high concentrations occasionally caused transient inhibition immediately after their application. This inhibition may be due to the synaptic influences produced by the excitation of other neurones. Some of the substances examined, lysergine, agroclavine, elymoclavine, festuclavine, nicergoline and lergotrile, at high concentrations caused abnormal spike discharges of TAN such as doublet or triplet spikes.

Animals↗
PubMedDate not supplied

[Selection of ergot alkaloid producers by induced mutagenesis].

Using the induced mutagenesis technique, A series of genetically modified Claviceps sp. VKM F-2609 strains that display high levels of agroclavine and elymoclavine synthesis were selected by induced mutagenesis. Compared to the parent strain, c106 displayed a 40-fold higher level of agroclavine synthesis, and c66 displayed an eightfold higher level of elymoclavine synthesis. The levels of synthesis of other alkaloids were decreased in these strains. The effects of various carbohydrates on the strain growth and ergot alkaloid biosynthesis was then investigated in both the parent strain and c106. The largest amount of agroclavine was synthesized by c106 strain growing on a medium with maltose.

Claviceps↗
PubMed1991

Comparative evaluation of lisuride and terguride, ergot alkaloid derivatives, on the field-stimulated vas deferens of mouse.

The ergot alkaloid derivatives, lisuride (LIS) and terguride (TDHL), known to interact with central dopamine receptors as agonist and partial agonist, respectively, were studied on the field-stimulated mouse vas deferens, where recently the existence of presynaptic dopamine receptors has been evidenced. LIS was a competitive antagonist at prejunctional alpha 2 and DA1 receptors situated on the sympathetic nerve terminals of the mouse, with a pA2 value of 9.2 and 9.1, respectively. LIS was also able to antagonize the effects of LY 171555, selective DA2 agonist, but the type of interaction cannot be conceptualized in terms of competitive antagonism. Likewise, the type of interaction of TDHL with dopaminergic and adrenergic agonist-activated sites is not suggestive of a competitive antagonism. Based on these results, it seems that central and peripheral pharmacologic profiles of LIS and TDHL cannot be overlapped, LIS being a potent DA1- and alpha 2-antagonist with a high degree of specifity for these receptors.

2,3,4,5-Tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-ben↗
PubMed1990

Actions of non-peptide ergot alkaloids at 5-HT1-like and 5-HT2 receptors mediating vascular smooth muscle contraction.

This report describes the actions of the non-peptide ergot alkaloids methysergide, methylergometrine and ergometrine at two types of 5-HT receptor mediating vascular contraction; the well established 5-HT2 receptor in rabbit aorta and a non-5-HT2 receptor in rabbit saphenous vein which resembles the 5-HT1-like receptor in dog saphenous vein. In the rabbit aorta ergometrine (1 mumol/l) and methylergometrine (0.3 mumol/l), but not methysergide, produced small contractions (14% and 7% respectively of the maximal response to 5-HT). This contraction was not related to activation of 5-HT2 receptors since it was resistant to blockade by ketanserin (0.3 mumol/l). When examined as antagonists of 5-HT-induced contractions of rabbit aorta, each ergot displayed nanomolar affinity at the 5-HT2 receptor but only methysergide behaved as a simple competitive antagonist (pKB = 8.25). Methylergometrine and ergometrine produced surmountable blockade which was accompanied by a non-parallel displacement of the 5-HT concentration-effect curves. The selective 5-HT1-like receptor agonist GR43175 (less than or equal to 30 mumol/l) was devoid of affinity at the 5-HT2 receptor in rabbit aorta. In the rabbit saphenous vein each of the ergots produced concentration-dependent contractions which resulted in overtly biphasic concentration-effect curves. Only the first phase of contraction mimicked the effects of 5-HT and GR43175 since contractions were not blocked by MDL 72222 (1 mumol/l), but were surmountably antagonised by methiothepin (10 nmol/l), ketanserin (0.3 mumol/l) and spiperone (0.3 mumol/l).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1984

Maximum oxygen consumption rate and dihydrogenated ergot alkaloids in humans.

The relationship of maximal oxygen uptake (VO2 max) with dihydrogenated ergot alkaloids was investigated in twelve young men. They were subjected to graded bicycle exercise with work loads corresponding to 75% and 120% of the load necessary to elicit VO2 max. The exercise tests were performed after intravenous administration of 2 mg dihydroergostin (DE-145) as well as after saline as control, both preparations were given double-blind. VO2 max averaged (SD) 3.36 (0.41) 1/min and no significant difference was disclosed between the DE-145 and the control situation. Normal relationships were observed between VO2 and work load, ventilation, heart rate, cardiac output, central venous pressure and acid-base data, and these relations were unaffected by DE-145 administration. Nausea was constantly seen in all subjects tested with DE-145. It is concluded, that the present dose of DE-145 has no influence on the functional capacity of the oxygen transporting system in sedentary young men.

Adult↗
PubMed1984

Simultaneous study of cerebral blood flow, vascular bed and deoxyglucose in aged rats. Effects of two dihydrogenated rye ergot alkaloids.

The influence of aging and the effects of treatment with dihydrogenated rye ergot alkaloid on cerebral hemodynamics and metabolism were studied in Long-Evans rats. Cerebral blood flow (CBF) was not affected by aging whereas the vascular bed and the uptake of deoxyglucose were significantly lower in aged than in young rats. 20 days after ligation of a carotid artery the blood flow on the same side of the brain, the vascular bed and the uptake of deoxyglucose were significantly lowered in aged rats as opposed to young rats. The second carotid artery was ligated 1 h before the animals were sacrificed: in the corresponding cerebral hemisphere the blood flow was found to be significantly lowered in young rats and even more so in aged rats. These results show that young rats are more likely to adapt to an acute or chronic circulatory deficiency than aged rats. Dihydroergocryptine ( DHEC , 0.1 mg/kg/day for 5 days, p.o.) reduces CBF and the vascular bed in aged rats, as opposed to dihydroergotoxine ( DHET , 5 X 0.1 mg/kg/day p.o.). The uptake of deoxyglucose was not influenced by the treatments. After ligation of the carotid arteries, treatment with DHEC and DHET induced an increase in CBF without any change in the vascular bed and, in the case of DHEC only, there was a significant increase in the uptake of deoxyglucose in the cerebral hemisphere submitted to acute circulatory deficiency. DHEC and DHET thus exerted significant effects on cerebral metabolism and hemodynamics in the aged rats after repeated oral treatment.

Aging↗