Effects of aging on alpha 1-adrenoceptor mechanisms and the inhibitory effect of diltiazem on noradrenaline maximum response in isolated rat aortic preparation

The effects of aging on alpha 1-adrenoceptor mechanisms in aortic preparations isolated from 3-, 6-, 10-, 18-, and 40-week-old rats were studied and compared with serotonin receptor mechanisms in the same preparations. The potency (pD2 value) of noradrenaline increased with age from 3 to 10 weeks, but decreased thereafter with age from 10 to 40 weeks. The affinity (pKA value) of noradrenaline and of prazosin (pA2 value) did not alter with aging. The change in potency or the pD2 value of noradrenaline was proportional to receptor reserve (pD2-pKA value) for noradrenaline, suggesting that the change of potency of noradrenaline with age was due to a change of receptor reserve, but not to change of drug affinity to alpha 1-adrenoceptors. The potency (pD2 value) and affinity (pKA value) of serotonin, and the affinity (pA2 value) of ketanserin, did not alter with aging, suggesting that serotonin receptor mechanisms in rat aorta did not change with age. The inhibitory effect of diltiazem on noradrenaline maximum response decreased with age from 3 to 10 weeks, but increased with age from 10 to 40 weeks. An inverse relationship between changes of diltiazem inhibition and receptor reserve of noradrenaline was found. Diltiazem's inhibitory effect on serotonin maximum response did not alter with aging.     

α-Amylase in the Barley Grain Influenced by the Auxin-Cytokinin Interaction in the Coleoptile

Two phases are distinguished in the α-amylase production in barley (Hordeum vulgare) grains. There is an increase in activity extended to the third or fourth day of germination, then a slight decrease follows. This decrease is accelerated by kinetin while it is prevented by IAA applied at the top of the embryo coleoptile. IAA reverses partially the kinetin action. IAA applied in the germination medium has practically no effect. Removal of the coleoptile stops further increase in α-amylase activity and induces complete insensitivity to hormone treatment. The results indicate that auxin metabolism in the coleoptile participates in the control of α-amylase evolution in the barley grain and that kinetin could act through auxin metabolism in this coleoptile.     

Polyclonal B-cell stimulative and immunosuppressive activities at different developmental stages of Trypanosoma gambiense

Bloodstream trypomastigote and cultured procyclic (insect midgut) forms of a monomophic strain of Trypanosoma gambiense were tested for their abilities to induce polyclonal B-cell activation (PBA) and immunosuppression (IS) in mice. Injection of a cell homogenate of bloodstream trypomastigotes induced both PBA and IS, while neither PBA nor IS was observed in mice injected with a cell homogenate of cultured procyclics. The results indicate that the substance(s) inducing PBA or IS is related to the developmental stage of the parasites.     

Eyelid reconstruction in pachydermoperiostosis

Our experience with an unusual case of pachydermoperiostosis is described. This case was accompanied by enlargement of the eyelids, excessive secretions, and difficulty in opening the eyes. Partial and serial excisions of the upper and lower eyelids were done to correct the thickened eyelids. As a result of the operations, this patient can open his eyes fully and the secretions have decreased.     

Changes in the content of atrial natriuretic factor with the progression of hypertension in spontaneously hypertensive rats

In order to assess possible roles of atrial natriuretic factor (ANF) in spontaneously hypertensive rats (SHR), we examined the content of immunoreactive-ANF in plasma, the atria, hypothalamus and pons of SHR and Wister Kyoto (WKY) rats by radioimmunoassay at different stages of age. With the progression of hypertension, plasma concentration of ANF increased whereas it decreased in the atria in SHR. This suggests ANF is secreted in response to hypertension. On the other hand, at hypothalamus and pons, ANF content was significantly higher in SHR than in WKY rats. This finding suggests possible involvement of ANF in the central regulation of blood pressure.     

AUSWIRKUNGEN VON INSEKTIZIDBEHANDLUNGEN AUF DIE EPIGÄISCHEN RAUBARTHROPODEN IN GETREIDEFELDERN,INSBESONDERE DIE LAUFKÄFER (COLEOPTERA,CARABIDAE)

Zusammenfassung Die Ergebnisse wurden mit Bodenfallen in Getreidefeldern erarbeitet. Fenitrothion beeinflußte bei Flugzeugausbringung in normaler Dosierung (600 g/ha in 40 1 Wasser) nur die Populationsdichte von Pterostichus vulgaris und P. niger vorübergehend. Eine Spritzung mit erhöhter Dosierung (900 g/ha in 350 1 Wasser) wirkte sehr stark auf die fünf häufigsten Carabidenarten ein. Parathion-äthyl beeinflußte in normaler Dosierung (125 g/ha in 300 1 Wasser) bei einer Behandlung Anfang Juni besonders einschneidend die Frühlingstiere, Ende Juni stark die Frühlings- und die Herbsttiere. In doppelter Dosierung reduzierte es alle wichtigen Prädatorengruppen sehr deutlich. Parathion-methyl (Staub) wirkte bei Ausbringung auf feuchte Pflanzen (200 g/ha) nicht stark auf die epigäischen Räuber. Nur kletternde Arten (Staphyliniden und Agonum dorsale) wurden geschädigt. Methoxychlor wirkte als Spritzmittel (600 g/ha in 300 1 Wasser) stark auf die großen Carabiden, während die kleinen Laufkäferarten, die Staphyliniden und Spinnen nicht beeinflußt wurden. Methoxychlor-Staub, auf die feuchten Pflanzen ausgebracht (1000 g/ha), beeinflußte die epigäischen Räuber nicht. Eine Randbehandlung eines Winterrapsfeldes mit Methoxychlor-Staub störte die Besiedlung des Feldes durch Carabiden und Staphyliniden nicht.

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Summary The influence of some insecticides often used in agriculture upon the terrestrial predaceous arthropods was investigated by pitfall trapping on cereal fields of about 10 hectares each, half the area of which was treated.Fenitrothion, sprayed by aeroplane at the normal dosage (600 g/ha in 40 1 water) influenced the abundance of Pterostichus vulgaris and P. niger only, for a short period. Spraying fenitrothion at a higher dosage (900 g/ha in 350 1 water) killed a high percentage of the five most common carabid species.Parathion-ethyl at the normal dosage (125 g/ha in 300 1 water), sprayed at the beginning of June reduced numbers of spring breeders especially (e.g. Pterostichus cupreus). Sprayed at the end of June, it influenced both spring and autumn breeders (e.g. P. vulgaris). Rain, falling one day after the insecticide treatment, did not alter its effect upon the terrestrial predators. At a higher dosage (250 g/ha) parathion-ethyl reduced numbers of all predators to a large extent, but not very much more than at the normal dosage.Parathion-methyl dust, applied to moist plants (200 g a.i./ha), did not influence all terrestrial predators, but only those species which also climb up the plants (some staphylinids and Agonum dorsale).Methoxychlor emulsion, sprayed at a dosage of 600 g/ha in 300 1 water, killed the bigger ground beetles only (Carabus spp. and P. vulgaris), but not the smaller ones (Agonum dorsale and Bembidion lampros), the staphylinids and the spiders. Methoxychlor, dust, applied to moist plants (1000 g a.i./ha) did not influence the terrestrial predators. Treating the edge only (ca. 20 m) of a winter-rape field with methoxychlor dust did not prevent the colonization of the field by carabids and staphylinids. It is recommended, therefore, to treat the field edges only, which should control most cereal pests.