Intestinal vasodilatation after mechanical stimulation of the jejunal mucosa

Zusammenfassung Mechanische Reizung der Dünndarmmukosa bewirkt eine Zunahme in der gesamten Durchblutung des Dünndarms bei der Katze. Diese vermehrte Durchblutung wird nicht beeinflusst durch Denervierung und/oder Ganglienblockade.     

Culture of presumptive epithelial cells from jejunal mucosa of axenic rats

Summary Strains of presumptive epithelial and fibroblast cells were prepared from the jejunal mucosa of axenic rats. Cells were cultured on collagen gels, in highly enriched media supplemented with homologous sera and hormones, and were maintained for more than 7 weeks.Supported by the Medical Research Council (Canada). The authors gratefully acknowledge the advice of Dr P. Rae of this institute.     

Activation of sustained sympathetic vasodilatation in dog by spinal cord stimulation

Summary Electrical stimulation in lateral sites of the upper cervical spinal cord evoked vasodilatation after adrenergic blockade. Sympathetic fibres mediating sustained vasodilatation were shown to be separate from adrenergic sympathetic fibres since the adrenergic vasoconstrictor response in the paw evoked by vasomotor stimulation in the medulla was not reversed to vasodilatation after bretylium.Supported by USPHS Grant No. HL 08570 and part of thesis work by Dr.Rolewicz.     

Activation of sustained sympathetic vasodilatation in dog by spinal cord stimulation.

Electrical stimulation in lateral sites of the upper cervical spinal cord evoked vasodilatation after adrenergic blockade. Sympathetic fibres mediating sustained vasodilatation were shown to be separate from adrenergic sympathetic fibres since the adrenergic vasoconstrictor response in the paw evoked by vasomotor stimulation in the medulla was not reversed to vasodilatation after bretylium.     

Electron microscope autoradiography of the mouse fundic mucosa after injection of tritiatedl-DOPA

Zusammenfassung Nach Injektion von³H-DOPA wurde bei der Maus im Fundus des Magens ultrastrukturell-autoradiographisch eine Markierung von zwei verschiedenen endokrinen Zelltypen festgestellt.     

Electrophysiological investigation on the antennal receptors of the silk moth during chemical and mechanical stimulation

Zusammenfassung Die isolierte Antenne vonBombyx beantwortet eine Duftreizung mit erhöhter Signalfrequenz vorher spontanaktiver und dem Signalisieren vorher ruhender Chemorezeptoren. Auf Duftströme reagiert das Sinnesorgan mit einer langsamen Potentialschwankung, demElektroantennogramm (EAG). Luftströme erregen in Schwingungsrezeptoren frequente Entladungen und löschen in Druckrezeptoren spontane Spikes aus.     

Decreased cyclic GMP levels in rat cecum mucosa during adaptive stimulation of Na-K-ATPase.

In rat cecal mucosa, Na-K-ATPase specific activity and sodium and fluid absorption were increased by giving polyethylene glycol administration with the drinking water. Whereas cyclic AMP levels were unchanged, cyclic GMP was reduced by about 50%. This finding suggests a regulatory role of cyclic GMP in intestinal sodium and fluid absorption.     

Intestinal absorption of glucose immediately after vincristin administration in rats

Summary Vincristin leads to a time-dependent decrease of glucose absorption. Thus it is not possible to combine experiments which seek simultaneous information on intestinal absorption and epithelial replacement.Acknowledgements. I amd greatful to Prof.R. M. Clarke (Newcastle, NSW, Australia) and to Prof.T. Nevalainen (Kuopio, Finland) for their helpful discussions and to Ms.Johanna Breitsameter for technical assistance. This work was supported by the Deutsche Forschungsgemeinschaft, Bonn (SFB 112 project No. E 4).     

Decreased cyclic GMP levels in rat cecum mucosa during adaptive stimulation of Na−K-ATPase

Summary In rat cecal mucosa, Na–K-ATPase specific activity and sodium and fluid absorption were increased by giving polyethylene glycol administration with the drinking water. Whereas cyclic AMP levels were unchanged, cyclic GMP was reduced by about 50%. This finding suggests a regulatory role of cyclic GMP in intestinal sodium and fluid absorption.Acknowledgments. We thank Miss U. Kautz for engaged technical assistance, Dr G. Schultz, Pharmakologisches Institut der Universität Heidelberg, for valuable discussions and suggestions, and Dr. K.D. Schultz, Heidelberg, for generous supply of the cGMP antibody and 125-iodinated succinyl tyrosyl methyl ester of cGMP.Supported by the Deutsche Forschungsgemeinschaft, grant Lo 114/7.     

Intestinal vasoactive peptide receptors in enterocytes : specific binding and stimulation of cyclic AMP]

Receptors for the vasoactive intestinal peptide (VIP) were characterized on enterocytes isolated from Rat small intestine. Native VIP inhibited competitively the binding of 125I-VIP to enterocytes and strongly stimulated cyclic AMP production; both these effects were observed for concentrations of VIP as low as 0.5-1.0 ng/ml (0.15-0.30 nM) which are compatible with the VIP concentration in the gut.     

The responsiveness of acoustic area after stimulation of the caudate nucleus

Riassunto La stimolazione ad alta frequenza e di breve durata del nucleo caudato determina inibizione dei potenziali evocati nell'area uditiva primaria e secondarie sia in animali preparati acutamente sia in animali portatori di elettrodi a dimora.     

Intestinal glucose absorption in rats after secondary infections withNippostrongylus brasiliensis

Summary A challenge infection ofNippostrongylus brasiliensis in immune rats resulted in an earlier onset of intestinal glucose malabsorption and increased glucose metabolism compared with rats receiving a primary infection. Intestinal absorption and metabolism recovered to control levels earlier during a secondary infection. The pattern of changes in absorption and metabolism was probably related to host immunological activity.