Effect of stress on choline acetyltransferase activity of the brain and the adrenal of the rat

Choline acetyltransferase (ChAT) activity was determined in cerebral cortex, hypothalamus, hippocampus, cerebellum, medulla oblongata, midbrain and adrenal gland of rats exposed to acute or chronic stress. The exposure of animals to acute immobilization and cold stress (4°C) for one hour resulted in a significant decline of ChAT activity in all brain regions examined except for the medulla oblongata. Moreover, the exposure to acute stress resulted in significant increase of the same enzyme in the adrenal gland. However, chronic exposure of animals to cold stress (4°C) for 7 days resulted in no significant changes of ChAT activity in all tissues examined except for a decline in the midbrain and an increase in the medulla oblongata. The administration of corticosterone (2.0 mg/kg) 1 h prior to sacrificing caused an effect similar to that of acute stress on ChAT activity in all brain regions except for the hypothalamus and the cerebellum. It was concluded from this experiment that stress-induced changes in the ChAT activity of specific brain regions might be mediated by the adrenal steroids.This work was supported by a grant from the National Aeronautics and Space Administration (NSG 2183 and NAG 2-411), a grant from the National Institutes of Health (NIH RR 0811) and a grant from the Division of Research Resources (NIH grant RR 03020).     

Effect of stress on choline acetyltransferase activity of the brain and the adrenal of the rat.

Choline acetyltransferase (ChAT) activity was determined in cerebral cortex, hypothalamus, hippocampus, cerebellum, medulla oblongata, midbrain and adrenal gland of rats exposed to acute or chronic stress. The exposure of animals to acute immobilization and cold stress (4 degrees C) for one hour resulted in a significant decline of ChAT activity in all brain regions examined except for the medulla oblongata. Moreover, the exposure to acute stress resulted in significant increase of the same enzyme in the adrenal gland. However, chronic exposure of animals to cold stress (4 degrees C) for 7 days resulted in no significant changes of ChAT activity in all tissues examined except for a decline in the midbrain and an increase in the medulla oblongata. The administration of corticosterone (2.0 mg/kg) 1 h prior to sacrificing caused an effect similar to that of acute stress on ChAT activity in all brain regions except for the hypothalamus and the cerebellum. It was concluded from this experiment that stress-induced changes in the ChAT activity of specific brain regions might be mediated by the adrenal steroids.     

Organophosphate-mediated inhibition of choline acetyltransferase activity in rat brain tissue

Administration of the organophosphate compound soman in rats resulted in an inhibition of choline acetyltransferase activity in almost all brain regions examined. Enzyme activity was inhibited by 20-50% in various brain regions 30 min after soman injection (94-120 micrograms/kg). Enzyme activity in two regions decreased with time to a near zero level by 3 h after injection.     

Organophosphate-mediated inhibition of choline acetyltransferase activity in rat brain tissue

Summary Administration of the organophosphate compound soman in rats resulted in an inhibition of choline acetyltransferase activity in almost all brain regions examined. Enzyme activity was inhibited by 20–50% in various brain regions 30 min after soman injection (94–120 g/kg). Enzyme activity in two regions decreased with time to a near zero level by 3 h after injection.Research sponsored by the Air Force Office of Scientific Research/AFSC, United States Air Force, under Contract F49620-82-C-0035. This work was also supported by PHS MBRS Grant No. RR08037. The cooperation of Dr G. Goddard of the School of Aerospace Medicine, Brooks AFB, is gratefully acknowledged.     

Cholinesterase activity in skeletal muscle after botulinum toxin

Zusammenfassung Bei Zufuhr von Botulinum-A-Toxin in den Muskel Tibialis anterior der Ratte war die Cholinesteraseaktivität nach zwei Wochen herabgesetzt, jedoch weniger ausgesprochen als nach zweiwöchiger Denervierung des Muskels.     

Peroxidase activity and thiocyanate accumulation in salivary glands

Summary Salivary glands with high, low, or no peroxidase activity do not differ in [S¹⁴CN^–] after the i.v. injection of KS¹⁴CN, nor do the glands differ from blood and muscle in [S¹⁴CN^–]. The content of SCN^– in a salivary gland does not mirror the gland's participation in the peroxidase-mediated antimicrobial mechanism.     

Rate of fall in choline acetyltransferase activity in denervated diaphragms as dependent on the length of the degenerating nerve

Zusammenfassung An narkotisierten Ratten wurde der rechte Nervus phrenicus im Thorax entweder so hoch wie möglich, oder unmittelbar oberhalb des Diaphragms durchschnitten. Zwei Tage später erwies sich die Cholinacetyltransferase-Aktivität in der rechten Hälfte dann wesentlich geringer, wenn der Nerv distal statt proximal durchschnitten wurde.     

Effects of guanethidine on salivary glands

Zusammenfassung Guanethidin hebt den sekretorischen Effekt der Sympathicusstimulierung von Speicheldrüsen genau so wirksam auf wie Bretylium. Ebenso wie Bretytylium kann Guanethidin eine Speichelsekretion hervorrufen, aber nur, wenn es in grosser Menge gegeben wird. Während Bretylium dabei einen Muskarineffekt hat, scheint Guanethidin durch Freisetzen von Catecholaminen an den sympatischen Nervenenden zu wirken.     

Cholinesterase in human salivary glands

Zusammenfassung Operativ frisch entnommene menschliche Speicheldrüsen (Submaxillaris und Parotis) zeigen Cholinesteraseaktivität. Hauptsächlich werden spezifische Esterasen gefunden. Die Aktivität der männlichen Parotis ist höher als die der weiblichen. Letztere zeigt eine Aktivitätsabnahme mit zunehmendem Alter.     

Role of salivary glands in the maintenance of midgut amylase activity inPeriplaneta americana L.

Summary It was experimentally demonstrated, by the surgical removal of salivary glands and severence of salivary ducts, that most of the amylase in the gut ofPeriplaneta americana comes from the salivary glands.We wish to acknowledge Prof. H. Swarup (Jiwaji University, Gwalior, M.P.) for working facilities provided at School of Studies in Zoology, Vikram University, Ujjain, M.P., and Council of Scientific and Industrial Research, New Delhi, for fincancial support in the form of Junior Research Fellowship to one of us (O.P.A.)     

Adrenergic nerves in the major salivary glands of the rabbit

Zusammenfassung Es ist bekannt, dass die Ausbreitung der adrenergischen Speicheldrüsennerven der Ratte in enger Verbindung mit der Sekretion bei sympathischer Reizung steht. Die Submaxillaris- und Parotisdrüsen des Kaninchens waren reichlich mit adrenergischen Nerven versorgt. Die sympathische Sekretion der Submaxillarisdrüse war indessen sehr gering, während die der Parotisdrüse beträchtlich war. Die Versuche deuten darauf hin, dass die sympathischen Nerven nicht nur eine sekretorische Funktion haben.

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J. R. Garrett on leave from the Department of Oral Pathology, Kings College Hospital, London S.E. 5, wishes to acnowledge a travel grant made by theEley-Webster Trust.     

Effect of scorpion venom (Androctonus australis) on neuromuscular transmission inhibited by botulinum toxin in the frog]

We have shown that Scorpion venom restores the neuro-muscular transmission inhibited by Botulinum toxin in the Frog. The effectiveness of Scorpion venom was antagonized by excess magnesium.     

Modification of the action of pentagastrin on acid secretion by botulinum toxin

Summary I.v. botulinum toxin after 60–90 min abolished the dose-response relationship between pentagastrin and gastric acid secretion in anesthetized rats and guinea-pigs. The toxin reduced but did not abolish the acid stimulatory effect of histamine. As expected, the acid response to vagal stimulation was abolished and that to methacholine in rats was unaltered by the toxin.Acknowledgment. We are grateful to the generosity of Dr Edward J. Schantz, Food Research Institute, University of Wisconsin, for the botulinum toxin used. — This research was supported by NIH grant 1 RO1 AM 17125, The Secretion of Pepsin.     

Modification of the action of pentagastrin on acid secretion by botulinum toxin.

I.v botulinum toxin after 60-90 min abolished the dose-response relationship between pentagastrin and gastric acid secretion in anesthetized rats and guinea-pigs. The toxin reduced but did not abolish the acid stimulatory effect of histamine. As expected, the acid response to vagal stimulation was abolished and that to methacholine in rats was unaltered by the toxin.