The objective of this experiment was to develop a procedure for immunizing ewes against melatonin that would alter the effects of changing photoperiod on seasonal reproduction and prolactin secretion. Ewes were immunized against human serum albumin (HSA) as controls (n = 9) or a melatonin-human serum albumin conjugate (0.25 mg; n = 10) on December 14th (Day 0) and boosted 9 times. They were maintained on natural photoperiod and then transferred indoors and exposed to long days for 35 d, followed by short days for 146 d, long days for 93 d, and short days for a further 123 d. Antibody titers to melatonin (at a serum dilution of 1:1,250) were significantly higher in immunized ewes (27.3 +/- 6.6%) than controls (0.7 +/- 0.1%; P < 0.001). At the end of the experiment, antibody titers in immunized ewes (at dilution of 1:50) were higher in blood (43.7 +/- 8.2%) than in cerebrospinal fluid (10.8 +/- 3.9%; P < 0.05), and highly correlated (r2 = 0.746). Onset of the breeding season was advanced slightly after the second transfer from long to short days in immunized ewes (April 12 +/- 3 d) compared with controls (April 25 +/- 3 d; P < 0.05). Mean serum prolactin concentrations were lower (P < 0.05) in melatonin-immunized ewes compared with controls on natural photoperiod, after transfer from long to short days, during long days, and after the second transfer from long to short days. In conclusion, despite melatonin-immunization increasing antibody titers in blood and cerebrospinal fluid, and decreasing prolactin concentrations over much of the experiment, minimal effects on the timing of reproductive transitions in the ewes were evident. This discrepancy between the response of the prolactin and reproductive axes to melatonin immunization supports the hypothesis of a dual site of action of melatonin, with melatonin acting in the pituitary gland to mediate the effects of photoperiod on prolactin secretion and in the mediobasal hypothalamus to affect reproductive responses.

A new flavonoid di-C-glycoside, violarvensin (1), was isolated from the aerial parts of Viola arvensis, together with the known derivative violanthin (2). The structure of 1 was established as apigenin-6-C-beta-D-glucopyranosyl-8-C-beta-D-6-deoxygulopyranoside by spectral analysis.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

A successful synthesis of L-mimosylglycine is described. This peptide could be an antagonist of an active fragment of an enkephalin. The structure of this novel peptide has been elucidated by exhaustive n.m.r. methods.

An experiment was conducted to determine whether active immunization against melatonin could modify the perception of abrupt photoperiodic changes in ewes. Two groups each containing six intact Ile-de-France ewes were submitted to alternate periods of short days for 2.5 months and long days for 2.5 days for about 70 weeks. Three series of active immunizations against a melatonin conjugate were carried out during the first of the three long-day periods. Control ewes were actively immunized at the same time against human serum albumin. Blood samples were taken once a week throughout the experiment to measure antibody titre and affinity, and prolactin and progesterone concentrations. Sera of all treated ewes demonstrated higher antibody titres than those of control ewes. Antisera were highly specific, as evidenced by the absence of displacement of iodinated melatonin in the presence of ten melatonin metabolites. Significant effects of photoperiod and of the interaction between treatment and photoperiod on prolactin concentration were detected. Prolactin concentrations in plasma of the control ewes were high during long days and low during short days. However, in the treated ewes, with the exception of the first period of long days, prolactin concentrations were not influenced by photoperiodic changes. Ovulatory activity of control ewes, as demonstrated by progesterone measurements, was stimulated by short days and inhibited by long days. In contrast, ovulatory activity of treated ewes, after a response identical to that of control ewes after the first photoperiodic shift from long to short days, showed a complete desynchronization of ovulatory activity relative to photoperiodic changes.(ABSTRACT TRUNCATED AT 250 WORDS)

An X-ray analysis of oraposide, previously reported as orobanchoside and isolated from Orobanche rapumgenistae confirms the originality of an unusual cyclic structure formed by an ether linkage between a glucose molecule and a 3,4-dihydroxyphenylglycol.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

The reaction of a bromoacetylthioester BrCH2CO-S-R (R radical in the coenzyme A series) with spermidine (Spd) derivatives is investigated and it is established that the adduct SpdCOCH2-S-R 1 is the product of the reaction. Parallel studies with model compounds show that this is a general reaction of bromoacetylthioesters. The synthesis of analogs of 1 is described and they correspond to inhibitors of the histone acetyltransferase.

Luteolin-7-glucoside and luteolin-7-glucuronide were isolated from Lycopus europaeus L. (Lamiaceae) and identified by 1H- and 13C-NMR spectroscopy. Luteolin-7-glucuronide proved to be active against PMSG in vitro as well as in vivo, whereas the other flavone glycosides occurring in the plant were completely inactive.

Poliumoside, forsythoside B, echinacoside and arenarioside, caffeic glycoside esters, were isolated from several species of Oleaceae. The poliumoside/forsythoside ratio distinguishes Jasminum nudiflorum from J. mesnyi. Arenarioside and forsythoside B act in Forsythia species as good hybridization markers.

A new and high-yielding procedure was described for the synthesis of 4-amino-6, 7-dimethoxy-2[4-[4 (4-aminophenyl) butanoyl]-1-piperazinyl]-quinazoline Ⅶ, the key intermedi- ate for the newly designed potential α_1-AR affinity/photoaffinity probes Ⅷa/Ⅸa.

Isolation and structural verification of two diastereomers of 2-amino-4-hydroxypentanoic acid allowed to propose the creation of two sub-sections Luridus and Satanas, in the Luridi section responsable of many nomenclatural and toxicologic discussions.

A specific chemical marker was found in the genera Suillas. Gomphidius

AbstractThe alkylation of the amine (II) yields the amidine (IV) (no yield given) as major product.

The present study was conducted to assess the binding of [125I]melatonin to frozen unfixed sections of pars tuberalis/median eminence tissue from Ile-de-France rams exposed or not exposed to light before slaughter. The specificity of [125I]melatonin binding to the pars tuberalis tissue was revealed by autoradiography and the magnitude of binding as related to the pars tuberalis area was determined after incubation and counting of pars tuberalis/median eminence sections. Subsequent studies with sections incubated with [125I]melatonin indicated that 1. the binding sites were saturable; 2. binding was stable for 24 h at 20 degrees C, but unstable at 28 or 37 degrees C; 3. melatonin and [127I]melatonin had a similar potency to compete with [125I]melatonin for binding sites, whereas other ligands such as serotonin or N-acetylserotonin were devoid of activity, and 4. by Scatchard analysis, the constant affinity Ka was found to be high in the 10(10) l/mol range. Rams exposed to light throughout the night prior to slaughter presented a significant increase in the apparent number of [125I]melatonin binding sites in comparison to animals maintained under darkness (2.25 +/- 0.30 vs 1.01 +/- 0.17 fmol/mm2 pars tuberalis, p less than 0.01), whereas Ka values were similar in both groups. These results indicate the presence of true melatonin receptors in the pars tuberalis of the ram. Furthermore, they suggest that their apparent number is light-dependent.

Synthese de rutinose a partir d'halogenure d'O-[desoxy-6 α-L-mannopyranosyl]-6 glucopyranosyle et de geraniol dans la pyridine via un O-[desoxy-6 α-L-mannopyranosyl]-6 O-geranyloxycarbonyl-1 β-D-glucopyranose